Acoustics in the Worship Space XI: The Organ and the Building

Suggestions for Organists

Laurence Libin is emeritus curator of musical instruments at The Metropolitan Museum of Art and honorary curator of Steinway & Sons. He has been editor-in-chief of the Grove Dictionary of Musical Instruments and president of the Organ Historical Society, where he initiated the Phoenix Project to provide advice about organ preservation and relocation. He lectures and consults internationally on instrument history, documentation, and conservation.

Much has been said and written about conservation of historical organs, but fine old instruments, and even newer ones in good condition, continue to vanish at an alarming rate, taking with them a precious part of our musical heritage. Conservation work, no matter how thorough, cannot ensure an organ’s survival. Unpredictable or seemingly unmanageable threats endanger organs, especially in churches, but also in schools, concert halls, museums, and other institutions, in storage and in private possession—wherever they are located, no matter how “safe.” Among these threats are fires and floods, destructive storms, vandalism, abandonment of buildings, changing liturgical and musical fashions, venal or uninformed custodians and property developers, and misguided government interference (such as laws prohibiting sale of instruments with legally imported ivory keys and stop knobs). Such risks are largely beyond the control of organists, but this is no reason to overlook sensible precautions. Above all, be aware and be proactive; an organ’s longevity and your job may depend on it.

Most organists nowadays recognize that historical organs are a scarce, irreplaceable resource for performers, music and cultural historians, students of design and engineering, and of course listeners. Obviously, we will never have more 20th-century and earlier organs (or pianos, or anything else) than exist right now; tomorrow we will inevitably have fewer. With this in mind, apart from conservation measures, what can we do to slow the pace of loss of organs and safeguard the unique information and opportunities they embody? 

Three paths are straightforward: prepare for disaster; carefully document important organs before disaster strikes, so vital data, at least, can be saved; and promote appreciation for these instruments. Costly restoration and conservation work are pointless if an organ then remains unprotected. Rather than grieve and cast blame after a loss, take preventive measures. Here are some ways to minimize risk and preserve information:

Prepare

1. Keep the organ and the area around and over it clean and ventilated, free of flammable material and obstacles, dampness, vermin, children, and other hazards. Regularly inspect the organ’s interior and surroundings for signs of leaks, cracked or crumbling surfaces, settling, infestation, mold, etc., and report and keep a record of any deterioration. Keep emergency apparatus (e.g., tarpaulins, large flashlight, class ABC—preferably dry chemical—fire extinguisher, ladder) handy near the organ—it’s cheap insurance.

2. Keep the loft, chambers, and blower room locked when the area is unsupervised. Securing the organ’s perimeter to prevent unauthorized access, especially to pipes, is mandatory. Adequate lighting with motion-detector switches can prevent accidents and deter vandals.

3. Invite your local fire protection officer and building manager to visit the installation with you (and with your organ technician if possible). Tour the chamber or case interior and blower room; explain the purpose and fragility of pipes, trackers, console, and other components; discuss how best to provide emergency access while as much as possible avoiding water damage and crushing; inspect the space above the ceiling and the blower room for fire hazards, bad wiring and plumbing, and presence of working fire alarms and extinguishers. Bad wiring should be replaced; intact old wiring and circuitry in good condition need not be unless required by code and insurance terms.

4. Give your phone number to the fire protection officer and local fire station and post it near the organ so you (or the organ technician or other alternate) can be contacted quickly in an emergency if the building office is closed and staff are absent.

5. Do not allow contractors to work unsupervised around or over the organ. Consult the building manager or project supervisor to ensure compliance, and don’t trust verbal assurances. Roofing and any work involving a heat source are particularly dangerous, so make sure fire extinguishers are nearby and easily located. 

6. Discuss rerouting water pipes (including for fire suppression systems), roof drains, steam and condensate lines, so these don’t pass above the organ; anything that could leak or drip eventually will.  

7. Install surge protection on electrical circuits to avoid frying if lightning strikes nearby.

8. Try to maintain reasonable climate control but know that HVAC (heating, ventilating, air conditioning) systems will break down, usually when most needed. Sudden drastic drops or peaks in humidity are more dangerous than gradual seasonal shifts. A sharp drop is likely when an unheated building is quickly warmed in winter. Discuss this risk with the building manager and explain the cost and wear-and-tear of frequent retuning of reeds, etc. Monitor fluctuating temperature and humidity levels at different heights within the organ and try to mitigate excessive swings before they cause damage. 

9. If any part of the organ or blower system stands at or below ground level in a flood-prone area, see if it can be elevated. If not, prepare to isolate it from encroaching water, including from backed-up drains. 

10. Communicate well and regularly with the organ technician especially about any problems you notice, and keep to a consistent inspection and maintenance schedule. Deferred maintenance busts budgets. A neglected organ that doesn’t perform reliably is more likely to be scrapped. 

Document

1. A stop list isn’t enough. The more important the organ, the more thorough documentation it deserves. Photos and audio recordings should supplement written descriptions, measurements, and drawn plans. No amount of documentation will enable construction of an exact replica of a lost organ and its acoustical setting, but work toward that goal as if the organ’s virtual survival depends on it.

2. Organs under threat (potentially, all organs) need informed advocates. Enlist volunteers—students, choristers, members of a congregation—in the task of documentation so they become familiar with the instrument and have a stake in its preservation. Collaborators may have skills such as mechanical drawing, close-up photography, 3D imaging, audio recording, or spreadsheet preparation, that needn’t involve handling pipes or other delicate parts. 

3. Review available models for documentation at varying levels of specificity; pick a level that matches your capabilities and don’t exceed your level of competence. If you need expert advice, get it; talk to your organ technician and to the builder or restorer, if possible. Like practicing music, documentation is a never-ending process that can be systematically learned, extended, and improved.

4. Start with basics, adding details as resources allow. Don’t overlook oral accounts; interview persons knowledgeable about the organ’s history.

5. Especially for pre-industrial organs, include measurement of pitch, temperament, and wind pressures; analysis of pipe metal composition and scales; identification of wood species; description of console and chest layouts, action type, and winding system; dimensions of keyboards (including size of keys and placement of accidentals, distance between manuals and between lowest manual and pedals, depth and weight of touch, and other quantifiable playing characteristics); details of tuning and voicing methods and of tool marks and construction guide lines; recording of makers’ and others’ inscriptions, plaques, markings on pipes, and graffiti; evidence of earlier states, e.g. prior location, façade decoration, previous voicing and tuning, stop list and mixture composition, pipe racking, original winding system, etc. Expert help is available; ask a museum conservator for advice and referrals. 

6. Don’t confuse precision with accuracy, but use common sense; measurements of a thousandth of an inch or fraction of a cent in pitch are practically meaningless. Clearly distinguish surmise and opinion from observed fact.   

7. Keep copies of the organ’s documentation, including original and revised design drawings, technical specifications, builder’s and rebuilders’ contracts, records of relocations, alterations, and major repairs, and everything else pertinent to its history, structure, and condition in a secure place apart from the building where the organ is located; if the building is destroyed, these vital records may be saved. Make sure several persons know where they are deposited, preferably in a well-managed archives, not in your closet.

8. Include among these papers a copy of the organ’s up-to-date insurance policy. If the organ isn’t insured, either as part of the building’s fabric or as a furnishing, make it so, because the policy can provide objective evidence of the organ’s condition and replacement value. This valuation can help forestall efforts to discard the instrument.  

9. Don’t rely too heavily on computerized data storage systems (including audio and picture files) that depend on electronic devices prone to obsolescence and glitches; tangible records can be more durable and long-lasting.

10. Start documentation now. Don’t wait for an instrument to become endangered but assume it already is. In addition to detailed conservation reports on specific organs, for example by the Göteborg Organ Art Center (GOArt), these books offer useful guidance: Jim Berrow, ed.: Towards the Conservation and Restoration of Historic Organs: A Record of the Liverpool Conference, 23–26 August 1999 (London: Church House Publishing, 2000); Robert Barclay: The Preservation and Use of Historic Musical Instruments: Display Case and Concert Hall (London and Sterling, Virginia: Earthscan, 2005), with bibliography; John R. Watson, ed.: Organ Restoration Reconsidered: Proceedings of a Colloquium (Detroit Monographs in Musicology/Studies in Music, No. 44) (Warren, Michigan: Harmonie Park Press, 2005); John R. Watson: Artifacts in Use: The Paradox of Restoration and the Conservation of Organs (Richmond, Virginia: OHS Press, 2010), with bibliography.

Promote

1. Obscure, overlooked, or neglected organs are most at risk. Register and describe such organs in regional and national indexes such as the American Guild of Organists’ New York City Organ Project, the Organ Historical Society’s Pipe Organ Database, the American Theatre Organ Society’s international locator, the British Institute of Organ Studies’ National Organ Register, etc. Such “official” recognition can be a first line of defense against disparagement, denigration, and disposal. 

2. Where local preservation commissions offer protection of cultural heritage, seek protected status for an organ based on its historical and continuing significance to the community, especially if the organ is an integral part of a historic building rather than a free-standing, removable furnishing. 

3. Don’t let an organ’s existence be taken for granted. Enlist allies such as choir members, music students and teachers, clergy, and enthusiastic congregants in communicating more generally why an organ is important, how it works, and that it requires regular maintenance and insurance just as an expensive automobile does. 

4. As a reminder to administrators, facility managers, budget committees, vestry, dean’s office, or other authorities, report at least annually on the organ’s use, condition, maintenance needs, potential problems and opportunities, and related matters for which their support may be necessary. Help them feel involved and accountable. Ultimately an organ’s survival is its owner’s responsibility.  

5. Try to establish an endowment to fund the organ’s future maintenance. Even a small but restricted endowment can be a bulwark against careless plans to dispose of a useful instrument, while not blocking its replacement by a more suitable one.

6. A well-known, cherished organ is less likely to be discarded or mistreated, so draw attention to an obscure instrument through positive publicity. Introduce it to the public by writing and photography (for example in church bulletins and local newsletters), performances and demonstrations and “virtual tours” disseminated by social media, encouraging visits to the organ loft, celebrity endorsements—whatever attracts favorable notice and enhances the organ’s stature today and for posterity.

7. For general audiences, avoid playing dreary music redolent of fusty churches. Program appealing works including transcriptions of popular music; commission new compositions for a particular instrument; involve other media (e.g. film, dance, dramatic reading, vocalists, live streaming) in performances; develop imaginative opportunities for an organ to be heard in non-liturgical circumstances.

8. If possible, make a well-maintained organ available at minimal or no charge for practicing by college organ majors and qualified students of private teachers, including of course your own students. Such hospitality can build a grateful constituency. 

9. Emphasize that an organ is not only a vehicle for music; its worth is not summed up exclusively in its sound. It can also be a striking architectural feature, it embodies sophisticated technology and refined craftsmanship, it can preserve tangible evidence of past practice in design and engineering, it displays commitment to certain enduring cultural values and symbolizes civic and institutional pride, it can be an inspiring memorial to loved ones and a monument to donors, among other valuable extramusical functions.

10. Don’t go it alone. Collaborate with musicians, educators, organ builders and technicians, concert promoters and patrons, record collectors, broadcasters, landmark preservationists, anyone who shares a desire to promote organs and organ music. Membership in the Royal College of Organists, American Guild of Organists, Organ Historical Society, British Institute of Organ Studies, American Theatre Organ Society, Westfield Center for Historical Keyboard Studies, Historical Keyboard Society of North America, Galpin Society, American Musical Instrument Society, and sister associations will expand one’s sphere of like-minded acquaintances. Professional organ builders’ societies should also support preservation initiatives.

Who you gonna call?

When I was an organ major at Oberlin in the mid-1970s, I had a part-time job working for Jan Leek, a first-generation Hollander who came to the United States to work for Walter Holtkamp and wound up as Oberlin’s organ and harpsichord technician. Traveling around the Ohio and Pennsylvania countryside with Jan making organ service calls, I learned to tune and learned the strengths and weaknesses of action systems of many different organbuilders. I moved back to Boston in 1984 with my wife and two young sons to join the workshop of Angerstein & Associates, where along with larger projects including the construction of new organs, I made hundreds of service calls. That workshop closed in 1987 when Daniel Angerstein was appointed tonal director for M. P. Möller, and I entered a decade during which I cared for as many as 125 organs each year as the Bishop Organ Company.

I’ve always been an advocate for diligent organ maintenance, but ironically, I’ve noticed in my work with the Organ Clearing House that century-old instruments that have never been maintained are sometimes the most valuable. The pipes are straight and true, the original voicing is intact, and there’s not a trace of duct tape anywhere. You remove a dense layer of grime (mostly carried out of the organ on your clothes) to reveal a pristine instrument. You might take that as an argument not to maintain an organ, but the truth is that I’ve found most of those organs in remote humble churches, where in many cases they haven’t been played for decades.

The challenge for the conscientious organ technician is not to leave a mark. If your tuning techniques damage pipes, you’re not doing it right. You should not leave scrape marks on the resonators with your tuning tools, and you shouldn’t tear open the slots of reed pipes. Cone-tuned pipes should stay cylindrical with their solder seams unviolated. Wiring harnesses should be neat and orderly, with no loopy add-ons. Floors and walkboards should be vacuumed and blower rooms should be kept clean.

There are legitimate excuses for fast-and-dirty repairs during service calls, especially if you’re correcting a nasty problem just before an important musical event. But if you do that, you owe it to the client to make it nice when you return.¹ And, when you do make a fast-and-dirty repair, you should adjust your toolkit to accommodate the next one. Did you use a scrap from a Sunday bulletin to refit the stopper of a Gedeckt pipe? Put some leather in your toolbox when you get home.

Many of the churches where I’ve maintained organs are now closed. Many others have diminished their programs and aren’t “doing music” anymore. Some tell me that they can’t find an organist, which is often because they’re not offering a proper salary, and some have “gone clappy.” In this climate, I think it’s increasingly important for organ technicians to be ready to help churches care properly and economically for their pipe organs.

Some churches charge their organists with curatorial responsibilities, purposely placing the care of the organ in the musician’s job description. Others do not, and it’s often a struggle to get boards and committees to grasp the concept of responsible care of their organs. It’s also important to note that while most churches once had full-time sextons or custodians, that position is often eliminated as budgets are cut. Lots of church buildings, especially larger ones, have sophisticated engineering plants that include HVAC, elevators, alarm systems, and sump pumps. The old-time church sexton knew to keep an eye on all that, and to be sure they were serviced and evaluated regularly. Hiring an outside vendor to clean the building does not replace the custodian. I think it makes sense for such a church to engage a mechanical engineer as consultant to visit the building a few times each year checking on machinery, and have volunteers clean the building.

A pipe organ is a machine like none other, a combination of liturgical art and industrial product. A layman might look inside an organ chamber and see a machine, but the musician sits on the bench facing a musical instrument. If you think that the governing bodies of your church don’t fully appreciate the value of their organ, I offer a few thoughts you might use to raise awareness.

“Cleanliness is next to Godliness”

It’s an old saw, but besides your personal hygiene, there’s likely nowhere in your life where it rings truer than in your pipe organ. After fire, flood, and vandalism, dirt is the worst enemy of the pipe organ. An organ technician knows that a fleck of dust getting trapped on the armature of a chest magnet or the surface of a pallet is enough to cause a cipher. The leg of a spider will wreck the speech of a trumpet pipe, most likely one of the first five notes of the D-major scale, ready to spoil almost every wedding voluntary.

But where did that dirt come from? When building windchests, windlines, bellows, and wind regulators, the organbuilder tries hard to ensure that there’s no sawdust left inside. I have an air compressor and powerful vacuum cleaner permanently mounted by my workbench so I hardly have to take a step to clean the interior of a project I’m finishing.

Assuming that the organbuilder delivered a clean organ, the first obvious place for an organ to pick up dirt is in the blower room. Many organ blowers are located in remote basement rooms, and in many cases, there’s no one changing the light bulbs in basement corridors, and there’s no one in the building who knows what that thing is. We routinely find blower rooms chock full of detritus—remnants of Christmas pageants, church fairs, flea markets, and youth group car washes. Organ blowers can have electric motors of five horsepower or more, and I often see 90 or 100-year-old motors that throw impressive displays of sparks when they start up. If the ventilation is obstructed, a fire hazard is created. That sign from the 1972 church fair isn’t that important. Throw it away.

To illustrate the importance of cleanliness, I share our protocol for cleaning a blower room:

• Seal the blower intake with plastic and tape.

• Close the circuit breaker that provides power to the blower so it can’t be started accidentally.

• Vacuum, sweep, wash walls, ceiling, floor, blower housing, wind regulators, and ductwork.

• Leave the room undisturbed for 48 hours to allow dust to settle before opening and starting the blower.

Likewise, if a church fails to cover and protect their organ while the floor of the nave is sanded and refinished, they can expect serious trouble in the future.

Identification

As organist, you might be the only person in the church who can identify the areas occupied by the organ. Designate organ areas as “off limits,” with access limited to the organ technician. Nothing good will happen if the organ chamber is used for storage of old hymnals or folding chairs. Nothing good will happen if teenagers find their way inside to create a secret hidey-hole.² Nothing good will happen if the altar guild puts a vase full of water on the organ console, and, by the way, nothing good will happen if you put your coffee cup there.

The organ’s tuning will almost certainly be disrupted if someone goes into the chamber out of curiosity. Most things inside pipe organs that are not steps lack the “no step” marking, like the touchy areas on an aircraft wing have.

Insurance

Maybe that 1927 Skinner organ in your church (lucky you) cost $9,500 to build. In the early 1970s, a new two-manual Fisk organ cost less than $40,000. I’m frequently called as consultant when a church is making a claim for damage to their organ, working either for the church or the insurance company, and I’ve been in plenty of meetings where bad news about the difference between loss and coverage is announced. It’s both possible and wise to have the replacement value of an organ assessed every five or ten years, with that value named on the church’s insurance policy.

If the organ at your church sustains $250,000 of damage because of a roof leak, and the replacement value of the organ is not specifically listed on the church’s insurance policy, a lot of discussion is likely to lead to a disappointment.

What makes good maintenance?

It’s not realistic to make a sweeping statement about how much it should cost to maintain an organ. Some instruments require weekly, even daily attention, especially if they’re large and complex, in deteriorating condition, and in use in sophisticated music programs. Some instruments require almost no maintenance. A newer organ of modest size with cone-tuning could go five years or more without needing attention.

I suggest that every organ should be visited by a professional organ technician at least once a year, even if no tuning is needed, even if every note plays perfectly, even if all the indicators and accessories are working. The lubrication of the blower should be checked, and the interior of the instrument should be inspected to guard against that one pipe in the Pedal Trombone that has started to keel over. If it’s not caught before it falls, it will take the pedal flue pipes with it. A four-hour annual visit would prevent that.

It’s usual for an organ to be serviced twice a year. While it’s traditional for those service visits to be before Easter and Christmas, at least where I live in the temperate Northeast, Christmas and Easter can both be winter holidays, so it makes more sense to tune for cold weather and hot weather, or for heat on, heat off.

Most organs do not need to be thoroughly tuned during every visit. In fact, starting over with a new “A” and fresh temperament every time can be counterproductive, unless it’s a very small organ. While the stability of tuning varies from organ to organ, most instruments hold their basic tuning well. I generally start a tuning by checking the pitch stops in octaves from the console, writing down a few that need tuning, and check the organ stop-by-stop for inaccuracies. I list a couple dozen notes that need tuning and a half-dozen stops that don’t need anything, and I list which reed notes (or stops) need to be tuned. In that way, I can build on the stability of tuning established over years, keeping the broad picture of tuning clear and concise.

Regular organ maintenance should include cleaning keyboards, vacuuming under pedalboards (the tuner keeps the pencils), checking blower lubrication, and noting larger things that will need attention in the future. Tuners, if you see cracks in a leather gusset on a wind regulator, make a note with your invoice that it will need to be releathered within several years. Your client doesn’t want to hear bad news, but they don’t want a sudden failure and emergency expense either.

When you should call

The better you know your organ, the easier to judge. I once received a panicky call from an organist saying the entire organ had gone haywire. He was abusive over the phone, and demanded that I come right away. I dropped everything and made the 90-minute drive to the church. Haughtily, he demonstrated the cause of his concern. It took me just a few seconds to isolate one pipe in the Pedal Clarion. If he had bothered to look, he could have played without the Clarion for weeks, but I couldn’t tell him that, and I’ve carried the memory of that unpleasant encounter for more than 30 years.

You should call your tuner/technician when:

• You hear a big bang from inside the organ. (Once it was a raccoon tripping a Havahart trap!)

• You hear unusual wind noise. (In some organs, a big air leak like a blown reservoir can lead to the blower overheating.) 

• You hear unusual mechanical noise, grinding, thumping, squeaking, etc.

• You find paint chips in organ areas. (Is the ceiling falling in?)

• The organ blower has been left on accidentally for a long time. It’s a long time for a blower to run between Sundays.

• And obviously, when something important doesn’t work.

When you should not call

Sudden changes in climate often cause trouble with the operation of a pipe organ. Several days of heavy rain will raise the humidity inside a building so Swell shutters squeak and stick, keyboards get clammy and gummy, and the console rolltop gets stuck. If you can manage, simply let the organ be for several days. When conditions return to normal, chances are that things will start working again. Likewise, excessive dryness can cause trouble.

A couple years ago, I was rear-ended in heavy traffic on the Hutchinson River Parkway in Westchester County, just north of New York City. I drive a full-size SUV and have a heavy-duty trailer hitch so while the Mercedes that hit me left a rainbow of fluids on the road under its crumpled radiator, the only damage to my car was that the back-up camera stopped working. As I’ve driven many hundreds of thousands of miles without one, I didn’t bother to get it fixed, and I’m still perfectly happy driving the car.

If there’s a dead note in the middle octave of the Swell to Great coupler, call me and I’ll fix it. It’s important to the normal use of the organ. If there’s a dead note in the top octave of the Swell to Choir 4′ coupler, and it’s spoiling a melody in a certain piece you’re playing, choose a different registration, or choose a different piece. One good way to head your church toward giving up on the pipe organ is to spend a lot of money on single repairs that don’t matter much to the music. Remember that your church pays me the same for mileage and travel time whether I’m doing a full service call with dozens of little repairs, or making a special trip for a single issue. A cipher is a bigger issue than a dead note.

It’s important to the long life of an organ not to “overtune.” Believe it or not, many churches in northern climes do not have air-conditioning, and it’s usual for temperatures to climb into the 90s inside the organ during the summer. If an organ was built, voiced, and tuned for A=440 at 70°, you’ll ruin the reeds—really ruin them—if you try to tune them to the Principals at 90°. It doesn’t make sense to wreck an organ’s reeds for one wedding, no matter who is the bride.

One of the most difficult tuning assignments I’ve had was at Trinity Church, Copley Square in Boston, in the early 1990s when Brian Jones, Ross Wood, and the Trinity Choir were making their spectacular and ever popular recording Candlelight Carols. It was surreal to sit in the pews in the wee hours of the morning, wearing shorts and a tee-shirt, sweltering in mid-July heat, listening to David Willcocks’s fanfare and descant for O come, all ye faithful. Everyone wanted the organ to be in perfect tune, but it was my job to be sure that the organ’s spectacular antique Skinner reeds would live to see another real Christmas. More than 200,000 copies of that recording have been sold, so lots of you have a record of that tuning!

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Remember what I said about those dead notes that are a nuisance but not critical to the use of the instrument? The most important part of the organist’s role in organ maintenance is keeping a list. Maintain a notebook on the console, and write down what you notice. You might hear a cipher in the middle of a hymn that goes away. If you can pay attention enough to identify anything about it (what division, what stop, what pitch), write it down. If you think of a question, write it down. Maybe you noticed a tuning problem during a hymn. Write down the hymn number and what piston you were using. I’ll play the hymn and find the problem.

When I make repairs, I can check things off your list, write comments about the cause, make suggestions for future repairs or adjustments, and invite you for coffee the next time. The console notebook is the most important tool for maintaining an organ.

Notes

1. As I write, I’m thinking of the three clients where I owe follow-up. You know who you are.

2. I once found a little love nest inside an organ, complete with cushions, blankets, candles, and burnt matches. What could happen?

Acoustic excellence is derived from wise design planning and decision-making regarding elements that are already “givens” within a project and budget

Acoustics in the Worship Space I, II, III, IV, V, VI, VII, VIII, and IX have appeared in The Diapason, May 1983, May 1984, January 1986, May 1987, April 1988, April 1990, July 1991, May 1992, and April 2009 issues respectively.

In today’s world and economy, costs and budgets loom large in almost all activities and endeavors. During discussions of new church building or renovation projects, it might not be uncommon to hear the following ideas expressed: “Good acoustics aren’t really worth it for the average worshipper who won’t notice or appreciate it—that’s just for the elite ‘Carnegie Hall crowd;’” or, “It will cost too much to have good acoustics, and we cannot afford it.” When these notions surface they can sometimes be the cause for a church being doomed to a less than excellent acoustic environment.

Scientifically and experientially, it can be proven that good acoustic settings are indeed noticeable and appreciated by many, and not only by the “Carnegie Hall crowd”! In fact, acoustic qualities such as speech intelligibility, musical balance, and rhythmic and tuning accuracy can be scientifically tested and documented as being perceived and valued by a cross section of the population. The notion that “regular folks” won’t notice good acoustics is just scientifically false!

Economic issues are often the most difficult to resolve in many projects. Reduced availability of funds, lack of confidence in the economy, and the fear of future economic conditions are often governing factors. Indeed, when constructing a new worship facility or remodeling an existing one, many important matters tug at the purse strings, and budgeting can often be a stressor to a project. That said, it would still be eminently beneficial to consider acoustic issues seriously, and not simply dismiss acoustic excellence as being unaffordable or unattainable. Acoustic excellence does not necessarily mean purchasing “extra” or expensive features. Often, acoustic excellence can be realized from wise decisions and design choices regarding elements that are already a given part of a project.  

The primary architectural factors that affect the acoustic environment include the geometric form of a room (does the structure’s cubic air volume and shape enhance or detract from good sound?), the interior materials of a room (to what extent do selected interior finishes reflect, absorb, or transmit sound energy in a structure?), and the location of key elements (do the relative proximities of things such as microphones, speakers, singers, organ pipes, instruments, and even potentially noise-generating equipment help or hinder sound perception?). Wise or poor design choices regarding any of these factors can result in acoustic excellence or disaster.  

Geometric form of a room

Geometric room forms can distribute and project sound evenly through a space, or can generate unwanted tonal focusing, echoes, and standing waves. Successful worship space geometries typically have generous cubic air volumes, longer and shorter axes, and unobstructed “line of sight” sound projection paths. Sound-diffusing wall and ceiling surface profiles and features will also contribute to even distribution and dispersing of sound energy. Alternatively, low ceilings, flat and parallel surfaces, concave forms, deep transepts, etc., typically limit acoustical potential and create echoes, “hot spots,” “dead spots,” flutters, trapping, and other unwanted and disturbing acoustical anomalies.

Interior materials of a room

Appropriate ratios of sound-reflective to sound-absorbing materials in a room can result in a vibrant and reverberative space that enlivens music and liturgical participation, and produces 

authoritative speech. Alternatively, excessive amounts of carpeting, draperies, and other sound-absorbing features can deliver a dull, dead effect that suffocates worship participation and leaves music and speech uninspiring. Having a carefully selected ratio of sound-reflecting to sound-absorbing materials, which results in an appropriate reverberation period, is essential to a worthwhile acoustic setting.  

Location of key elements

Then there is location! The relative placement of organ pipes and choir singers together will allow choristers to hear accompaniments and each other clearly and facilitate accurate rhythm and tuning. For example, positioning singers in an ensemble format, forward and below organ cases or chambers, can maximize musical potential. If singers are placed far from organ pipes, within restrictive alcoves, behind obstructions, or strung out in long lines, the entire musical ensemble will suffer from being disengaged. Similarly, the correct location of loudspeakers relative to both microphones and the listening congregation can assure speech intelligibility for all, while inappropriate placement of sound system components can result in frustration and lost clarity for all; if loudspeakers are placed with direct “line of sight” access to all listeners, they can deliver sound with clarity. Ultimately, it is not enough to have all of the sound sources and listeners “somewhere” in the room.  Relational locations and proximities are critical to success.

Finally, even if all of the beneficial acoustic design features for room geometry, material selections, and functional proximities are adopted, all can still be ruined if unwanted and interrupting noises invade the worship space. Techniques such as placing noise-generating equipment and functions away from the worship space, and using resilient mountings and discontinuous structures can mitigate “noise to listener” pathways.  

Acoustic excellence

In all of these examples, acoustic success is not derived from expensive treatments or extra apparatus. Acoustic excellence is instead derived from wise design planning and decision-making regarding elements that are already “givens” within a project and budget. It may cost no more or less to place organ pipes in good or poor proximity to choir singers! It may cost no more or less to place noise-generating air-conditioning compressors near or far from the worship space! It may cost no more or less to angle a wall profile to avoid or create an echo! In many instances, the good acoustic choice can indeed be the least costly choice. For example, a hard surface floor that reinforces sound energy will last a lifetime, while a carpeted floor that removes sound energy from an environment will wear over time and eventually require replacement.  

While significant acoustic success can be realized from informed design and decision-making, it should not be inferred, however, that all acoustic matters are free and easy! There are some acoustic benefits worth paying for. Hard, dense walls that reinforce and balance low frequency tone near organ pipes and choir singers are indeed more expensive than thin gypsum board, but the price of the thin walls can be perpetually brittle and “tinny” music. It may cost more to hoist heavy loudspeakers to a high ceiling location than to wall-mount smaller units, but the price of poor speaker placement is a missed opportunity to proclaim the word with clarity and intelligibility. It may cost more to line air-conditioning ducts to prevent noise transmission, but constant HVAC noise interrupting speech and music during worship ruins the experience for all. While these and similarly important acoustic details do have an initial price tag, the cost of remedying these details later is even greater. As a wise observer once said, “If you don’t have the funds to do it right the first time, where are you going to find the additional funds to do it over again?” So, the functional value of design decisions must also be considered along with cost.

Substantial and significant acoustic benefits can result from making wise choices about already-fixed costs. A building will have floors, walls, and ceiling; these can be designed to work in favor of a good acoustic environment through careful detailing, and not necessarily through additional expense. A good acoustical environment can be defeated through uninformed and unwise design, and not necessarily because of lack of spending! Great acoustical worship environments are indeed achievable, even on a budget. Careful overall planning that maximizes the acoustic potential of a design, combined with reasonable spending on priority features, can result in architectural, functional, and inspirational value for generations.

Photo credit: Scott R. Riedel & Associates.

Michael McNeil has designed, constructed, and researched pipe organs since 1973. He was also a research engineer in the disk drive industry with 27 patents. He has authored four hardbound books, among them The Sound of Pipe Organs, several e-publications, and many journal articles.

Editor’s note: Part I of this article was published in the July issue of The Diapason, pages 17–19.

Mouth heights 

Mouth height, or “cutup,” as it is more commonly called by voicers, is the primary means of adjusting the timbre of a pipe. Low cutups will create a brighter tone with many harmonics, while high cutups will produce smoother tone with fewer harmonic overtones. For interested readers, see The Sound of Pipe Organs, pp. 68–80. In older organs, it is not uncommon to find flute pipe mouths cut twelve half tones higher than principal chorus pipes.

In the Normal Scale of mouth heights, a higher cutup value on the vertical scale will result in smoother tone. Cutups may be adjusted higher for one or both of two reasons: 1) the voicer wants a smoother timbre, or 2) the voicer wants more power at the same timbre. More power means more wind, and this means a larger toe and/or flueway to admit more wind at the mouth. More wind at the mouth will always produce a brighter tone, so the voicer can make a pipe louder and preserve its original timbre by opening the toe and raising the cutup until the timbre is restored.

Now we can understand the graphs. In Figure 6 we see that the Hook principal chorus has high cutups and that they do not significantly vary from bass to treble. Hook pushes pipes to higher power with much more open toes (Figure 8), and the voicer raises the cutups to avoid a strident timbre at the increased power. The timbres are relatively constant from bass to treble. Note the lower mouth heights of the William A. Johnson Cymbal VII, which makes its timbre brighter than the Hook voicing (also note that the Cymbal’s toes are winded as robustly as the Hook pipes in Figure 8).

In contrast, the Isnard chorus in Figure 7 shows much lower cutups in the bass and mid-range, and much higher cutups in the highest treble. We will see in the data for toe diameters in Figure 9 that Isnard is restraining his pipes for less power and voicing for an ascending treble.

Pipe toe “C” values

Pipe toe diameters can be normalized to the diameter of the pipe, the width of the mouth, and a normalized depth of the flueway. For interested readers, the derivation of this normalization is explained in detail in The Sound of Pipe Organs, pp. 43–47. Higher “C” values mean the toe is larger and flows more wind relative to its mouth width and flueway depth. This is a primary voicing tool for regulating power.

The contrast in the toe diameters of these two organs is striking in many ways. The Hook toes in Figure 8 are much wider overall than the Isnard toes in Figure 9, demonstrating the primary source of the power of the Hook. This power would normally encourage chiff in the pipe speech, but this is suppressed in the Hook by the use of very deep and regular nicking of the languids of the pipes. Ninety percent of the Isnard pipes are free of nicks, and when nicks are found, there are typically only two or three very fine, shallow nicks on a languid. Contrast this with the treatment of the 16′ Open Diapason of the Hook: 22 fine nicks at C1, 20 nicks at c13, 29 nicks at c25, 24 medium nicks at c37, and 19 medium nicks at c49, all of the pipes having their nicks cut very deeply into the languid. There is no discernible “chiff” to the speech, but this is desirable for the interpretation of Romantic music. Interested readers can refer to The Sound of Pipe Organs, pp. 94–96, for a graphic illustration of the effects of such nicking on speech transients.

Figure 8 demonstrates another key element of the Romantic tradition—large toes supplying more wind and power to the bass and mid-range. In contrast, the toe constants of the Isnard are much smaller, more constant across the compass, more constant for all stops of the chorus, and exhibit a subtle rise to support an ascending treble. 

Flueway depths 

Like the pipe toe, the flueway depth also controls the flow of wind and strongly correlates to the power of the pipe. Interested readers can refer to The Sound of Pipe Organs, pp. 50–63 and 77–82. 

In Figure 10 we see another essential characteristic of Romantic voicing—a very deep flueway. Much of the Romantic voicing tradition grew out of the French Classical voicing style, which maintained deep flueways and controlled the power of a pipe by restricting its toe, much as we see in Figure 9. The restorer of the Isnard organ, Yves Cabourdin, noted that the flueways of the Isnard organ seen in Figure 11 are “closed up” relative to normal French Classic practice, yet the flueways of the Isnard are very deep relative to the common North German practice of regulating power by closing down the flueways while maintaining open toes. For interested readers, some examples of historical practice in flueway depths may be found in The Sound of Pipe Organs, pp. 50–51.

The extremely deep flueways of the Hook organ are consistent with Romantic voicing in general, along with more generous toe diameters and the nicking required to suppress chiffing in the pipe speech at the greatly increased power levels of this style. 

The flueways of the Hook organ appeared in general to be very well preserved and were very consistent. The anomalous lower value of the flueway in Figure 10 for the Hook 16′ Open Diapason at c25 (4′ pitch) may have been the result of handling damage to that pipe or modifications when the pitch was changed. The robust flueway depth of the Hook 16′ low C pipe is literally off the chart at 4.8 mm.

Ratios of toe and flueway areas

The flow of wind and power balances are controlled by the voicer at the toe and flueway of a pipe. The ratio of the area of the toe to the area of the flueway is important. If the area of the toe is less than the area of the flueway, which is a ratio less than 1:1, it will cause a significant drop in the pressure at the mouth, and what is more important, the speech will be noticeably slower. When the area of the toe and flueway are equal, the ratio is exactly 1:1, and this is the lower limit for pipes with faster speech. Interested readers can refer to The Sound of Pipe Organs, pp. 56–63 and 114–116 for a discussion of this very important musical characteristic and its effect on the cohesion of a chorus. (A well-knit chorus may contain slower pipes or faster pipes, but never both.)

The Hook ratios in Figure 12 never descend below a ratio of 1:1 and typically ascend to extremely high values in the treble. It is this technique with which Hook obtains an ascending treble.

The Isnard ratios in Figure 13 reside at a value of 1:1 for the bass and mid-range and ascend to much higher values at the highest pitches. Like the Hooks, the Isnards achieved an ascending treble with this technique, but unlike the Hooks, the Isnards crafted the bass and mid-range ratios to values of almost exactly 1:1. The Isnard pipe speech has a lovely “bloom,” which is a direct result of these very carefully crafted ratios; the term “bloom” refers to a slower buildup of power in the initial speech of a pipe. The Hook organ also exhibits a distinct bloom, but this bloom has no speech transients, and it derives from the low resonant frequency of the wind system when it is working hard to supply wind.

The wind system 

The design of the wind system plays a large role in the dynamics of the wind and the musicality of the organ. Dry acoustics favor faster wind systems, which support faster tempos; live acoustics fill dramatic pauses with a halo of reverberation and encourage slower tempos. Wind systems can be designed to enhance the grand cadences of historic literature written for live acoustics, and such wind systems will have a slower response. For interested readers, this response can be described as the resonant frequency of the wind system, and it is fully described in The Sound of Pipe Organs, pp. 99–113, using the Isnard organ as a worked example.

Documentation of the wind system is probably the most overlooked feature in descriptions of pipe organs. The Hook’s wind system was measured in some detail, but not completely due to the constraints of time.

The wind of the Hook organ has no perceptible shake. The tutti does not noticeably sag in pitch. The speech onset of the full Hook plenum is characterized by a dramatic surge, the result of weighted bellows and large system capacitances. The current wind system shows some modification of the 1863 design, largely as a result of the 1902 addition of the Solo Division. 

The static wind pressure of the Great was measured to be 75 mm water column at c′(25) of the 4′ Clarion, the last stop on the back of the chest. The static wind pressure at a′′′(58) of the 16′ Open Diapason was measured to be 76 mm; drawing all of the stops reduced that pressure to 67 mm.

All divisions in the organ are fed with ducts that have cross sections many times what is necessary to wind the tutti. These ducts are also very long, with the result that they are calculated to have Helmholtz resonances in the very low range of about 4 Hz; this frequency is not audible when the organ is played, suggesting that the damping of the wind system is considerable (some concussion bellows are present). The main ducts have about 0.56 m³ of volume.

The two bellows that together feed the Great and Choir (and originally also the Swell), are massive with 8.4 m³ of volume, having two inward folds and one outward fold. The resonant frequency of the two bellows, two pallet boxes of the Great division, and wind ducts as a function of their mass and volume is calculated to be 1.23 Hz. Such a low resonant frequency is the primary source of the grand surge in the tutti of this instrument. It is a musical wind with grand drama, exhibiting none of the nervousness of organs with sprung bellows. Both the mass and volume of this wind system compare favorably with the Isnard organ. And although the Hook organ features double-rise bellows and the Isnard features wedge bellows, they have very similar and low resonant frequencies at 1.23 Hz and 1.20 Hz, respectively. Figure 14 is a table showing the measurements of the wind system and its calculated resonance. 

Another important characteristic of a wind system is its wind flow and damping. The total demand on a wind system is equal to the areas of all of the toes of all of the pipes that can be played at the same time on full organ. We then look to see if the key channels can flow sufficient wind to those toes, if the pallets can flow sufficient wind to the key channels, and if the wind ducts can flow sufficient wind to all of the pallets. This analysis was performed on the Isnard organ (see The Sound of Pipe Organs, pp. 120–127), with the interesting result that the Isnard wind trunk just barely flows adequate wind for the coupled principal choruses of the Grand Orgue and Positif, but it is wholly inadequate for any form of tutti. This sort of restriction is not uncommon in older organs, and it performs the function of adding significant resistance to the wind flow, which in turn dampens Helmholtz resonances in the cavities of the wind system, e.g., wind shake from the wind trunks and pallet boxes. We do not have enough data for all of the stops of the Hook to perform this analysis, but the very large cross-section of the wind trunk suggests that it has much more winding than the Isnard, and that would be consistent with a Romantic organ and the requirement that it support a full tutti. The table in Figure 15 shows the data for wind flow in the windchests of the Great division.

The Great division 

There are two windchests for the Great division, split diatonically C and C# with the bass notes at the outer ends and a walkboard in the middle. Figure 16 shows the pipes on the C side windchest from the 8′ Open Diapason Forte at the left (front of the chest) to the treble end of the III Mixture at the right. The order of stops is:

8′ Open Diapason Forte

8′ Clarabella

16′ Open Diapason

8′ Viola da Gamba

8′ Open Diapason Mezzo

4′ Octave

4′ Flute Harmonique

3′ Twelfth

2′ Fifteenth

III Mixture

V Mixture

VII Cymbal (Johnson, 1870)

16′ Trumpet

8′ Trumpet

4′ Clarion

Figure 17 shows the treble end of the mixtures on the C side. The toeboard on the left contains both the III Mixture and V Mixture. From left to right, we see the III Mixture, V Mixture, and on the right toe board, the later addition of the VII Cymbal (red arrow).

Most of the treble pipes are cone tuned and exhibit almost no damage. This is a tribute to the tuning skills of the Lahaise family. Few organs of this age have survived with such intact mixture pipes. The pre-restoration photos of the Isnard organ at St. Maximin show the more typical fate of such pipes.

All of the tin-lead pipes in this organ are constructed of spotted metal, with the notable exception of the Cymbal (added by Johnson in 1870), which is planed metal. This accounts for the obvious difference in the construction of the rackboard for this stop. The VII Cymbal (red arrows) includes a third-sounding rank, and in the style of Johnson it is silvery (lower cutups) and restrained in power (very narrow pipe diameters and mouth scales). Although no records exist, there must have been a fascinating story behind the inclusion of a competitor’s mixture in this organ.

Figure 18 shows the back of the C side Great chest. The order of reed stops, from left to right, is: 16′ Trumpet, 8′ Trumpet, and 4′ Clarion. Note that the 4′ Clarion is cut dead length in all pipes except the newer, slotted low C pipe added at the time of repitching the organ. Trebles of the 16′ and 8′ ranks are also cut dead length without slots. The intent here is obvious: don’t tune these reeds on the scrolls, tune them on the wire.

General observations

16′ Open Diapason

All of the pipes of the 16′ Open Diapason from the mid-range downward into the deep bass exhibit very bright harmonic content. The reason for this becomes apparent with a close examination of the middle D pipe. When the organ was repitched from A=450 to A=435 Hz, a new low C pipe was made for many of the stops and the original pipes were moved up one half step. The tuning distance between 435 Hz and 450 Hz is less than a half step, with the result that the pipes were now much too flat. The scrolls were then rolled down to bring the pipes into tune at 435 Hz. We can see from Figure 19 that to achieve correct tuning on the middle D pipe, the tin-lead scroll was completely removed and the zinc resonator was crudely cut and broken to make the slot deeper.

This was apparently not sufficient to bring this pipe into tune. Figure 20 shows that the toe of this pipe was crudely opened and flared outward without the benefit of a normal toe reamer or toe chamfering tool. This is very informative because it explains the much brighter timbre of this pipe relative to its treble or other foundations. The opening of the toe increased the pitch and brought the pipe into tune, but at the expense of more power and a much brighter timbre relative to the original voicing. Even with this increased power it would have been possible to have preserved the original timbre by slightly raising the cutup. Inspection of the upper lips indicates that this was not done; the upper lips of all pipes are slightly skived to about one half of the metal thickness, and this was still intact on all pipes. Note that the crudely damaged toe shows bright metal; there was no bright metal on the upper lips, indicating original cutups but modified toes. This voicing damage is typical throughout the bass of this stop. 

Figure 21 shows the back of the low D façade pipe. Note that the tin-lead scroll is completely missing, the zinc is rolled back at the bottom of the slot, and the tin-lead adjacent to the top of the slot is bent outwards on both sides. The author verified that the wind to the toe was likely altered as well; the wooden slides in the toeboard that regulate wind flow were completely open. The façade pipes were all speaking on maximum wind. Figure 22 illustrates the condition of the scrolls in the back of the façade for 16′ c, 16′ G#, 8′ C, 8′ D, 8′ E, and 8′ F#, going from left to right in the figure.

8′ Open Diapason Forte

The cutups appear original, the toes were crudely opened, and this stop indeed sounds too loud and too bright relative to any other 8′ stop. In fact, this stop obliterates the sense of chorus when using it in the traditional French fonds. One would normally expect the 8′ Forte to be slightly more powerful, but less bright, than the 8′ Open Diapason Mezzo; they would then combine as a fine chorus. In fact, this stop is much more powerful than the Open Diapason Mezzo and also brighter. This rank shows the same tuning modification seen in Figure 19, and the toes of this rank were opened in the same crude manner seen in Figure 20. 

While there is some evidence of selective toe adjustment in other stops, no other ranks show such crude treatment and excessive opening of the toes. They have normal chamfers and round bores. Lending further evidence to the hypothesis that this was damage inflicted at the time of repitching the organ, it was seen that the same crude method of opening the toes was applied to all of the new low C pipes in all of the ranks.

We are fortunate in at least one respect. The workmanship during the repitching was very crude, and this allows us to better understand the order of events and the anomalous tonal balances.

III Mixture

The mixture pipes were all moved up one half step when the organ was repitched, widening the scales by a half step and moving the breaks up by the same amount. The new pipes added at low C were crudely matched in diameters, mouth widths, and toes. The width scales of the fifths are about two half tones narrower than the 4′ Octave, similar to the scaling of the Twelfth. The octaves are as wide as the foundations. The current breaks are:

C1 2′ 11⁄3′ 1′

c#26 4′ 22⁄3′ 2′

V Mixture

Although not measured, the flueways were visually consistent with other Hook stops. This mixture is scaled about 3 to 5 half tones narrower than the foundations. The current breaks are:

C1 2′ 11⁄3′ 1′ 2⁄3′ 1⁄2′

c#14 22⁄3′ 2′ 11⁄3′ 1′ 2⁄3′

c#26 4′ 22⁄3′ 2′ 11⁄3′ 1′

c#38 8′ 4′ 22⁄3′ 2′ 11⁄3′

c#50 8′ 51⁄3′ 4′ 22⁄3′ 2′

VII Cymbal (Johnson, 1870)⁴

Although not measured, the flueways were visually consistent with the other Hook pipework. This mixture, designed and built by William A. Johnson and installed in 1870, is 6 to 7 half tones narrower than the foundations. It has similar robust winding in its toes and flueways to the Hook work, but it is cut up relatively lower than the Hook mixtures, giving the Johnson mixture a more silvery timbre. It is a magnificent sound and provides a scintillating crown to the principal chorus of the Hook. Unlike the spotted metal of the Hook pipework, these Johnson pipes are all made of planed metal, probably containing Johnson’s typical alloy of 33% tin.⁵ This stop includes a third-sounding rank; its current breaks are:

C1 13⁄5′ 11⁄3′ 1′ 2⁄3′ 1⁄2′ 1⁄3′ 1⁄4′

c#14 2′ 13⁄5′ 11⁄3′ 1′ 2⁄3′ 1⁄2′ 1⁄3′

g20 22⁄3′ 2′ 13⁄5′ 11⁄3′ 1′ 2⁄3′ 1⁄2′

c#26 4′ 22⁄3′ 2′ 13⁄5′ 11⁄3′ 1′ 2⁄3′

g32 51⁄3′ 4′ 22⁄3′ 2′ 13⁄5′ 11⁄3′ 1′

d#40 8′ 51⁄3′ 4′ 22⁄3′ 2′ 13⁄5′ 11⁄3′

c#50 16′ 8′ 51⁄3′ 4′ 31⁄5′ 22⁄3′ 2′ ν

Notes and Credits

All photographs, tables, graphs, and data are by the author except as noted.

4. Huntington, Scot L., Barbara Owen, Stephen L. Pinel, Martin R. Walsh, Johnson Organs 1844–1898, OHS Press, Richmond, Virginia, pp. 17–18.

5. Elsworth, John Van Varick. The Johnson Organs, The Boston Organ Club Chapter of the Organ Historical Society, Harrisville, New Hampshire, 1984, p. 45.

To be continued.

Michael McNeil has designed, constructed, and researched pipe organs since 1973. He was also a research engineer in the disk drive industry with 27 patents. He has authored four hardbound books, among them The Sound of Pipe Organs, several e-publications, and many journal articles.

Editor’s note: Part 1 of this article was published in the July issue of The Diapason, pages 17–19. Part 2 was published in the August issue, pages 18–21.

Re-pitching of the Pedal 

In Figure 23 we see the C side of the Pedal 16′ Trombone in the front row, and the Pedal 16′ Open Diapason in the back row. Both stops have their pipes in the original position. Note the crude addition of boards to the top of the Trombone pipes as the means of lowering the pitch from A450 to A435 Hz. Relative to its original voicing, this stop is choked off in power and brilliance. Also note the more professional lengthening of the resonators of the Pedal 16′ Open Diapason pipes.

Impact of the Solo division 

The Solo division was added in 1902 as Opus 1959 of E. & G. G. Hook & Hastings, placing the windchest over the C# side of the Pedal and Great divisions. Figure 24 is a view from below up into the bottom of the Solo chest. The Pedal wood Trombone pipe in the center is speaking directly into the bottom of the Solo chest, muffling its tone. The Trombone pipe on the left has been mitered to clear the Solo chest.

In Figure 25 one can see that the low C# pipe of the Great 16′ Trumpet speaks directly into the bottom of the Solo chest. In an effort to restore the tuning and power to the pipe, the entire scroll has been crudely forced open. In Figure 26 one can see the more normal scroll of the unobstructed low C pipe of the Great 16′ Trumpet. The diatonic differences heard in the voicing of many bass pipes are entirely due to the unfortunate placement of the Solo division. The craftsmanship and engineering skills of 1902 were clearly inferior to those of 1863.

The change of pitch

The organ was originally pitched at A=450 Hz. Sometime before 1902 the organ was repitched to A=435 Hz.⁶ The current pitch of the organ, 435.3 Hz at 74 degrees F, was measured in June 2000 with a Widener electronic tuner using the 4′ Octave of the Great as the reference pitch, while confirming that this stop was in good tune with itself and the rest of the chorus. The tuning of the organ is quite stable as a result of the use of scrolls in the bass pipes, cone tuning for the trebles, and generous pipe flueways, which do not easily become choked with dust. 

Resonator lengths of the reeds

How did this change of pitch affect the timbre of the reed chorus? Raising the pitch of a reed pipe by pushing down on its tuning wire will eventually force it to overblow to its octave. As an overblowing reed pipe’s tuning wire is slowly raised and the pitch flattened, the pipe will at some point flip back to its fundamental pitch. This is called the “flip point,” and it represents the pitch with the warmest fundamental power. As the wire is raised further, tuning to yet lower pitches, the fundamental will weaken and the harmonics will strengthen in power. The same effect will occur if the resonator is shortened at the flip point. Most reed pipe resonators are adjusted to a length where the flip point is just slightly sharp of the desired pitch—the speech is faster and the harmonic balances are more pleasing with good fundamental warmth and some fire in the harmonics. A good resonator length is not so close to the flip point that it “flips” to the octave when it is tuned on the wire to the flue pipes on the hottest summer days, but it is close to that condition.

With this in mind, the author saw an opportunity to explore the flip points of the Hook chorus reeds. With the exception of the low C pipe, which was added when the organ was repitched to 435 Hz, the resonators of the 4′ Clarion were cut dead length with no scrolls and no evidence of having been shortened. This afforded the opportunity to explore the timbre of these stops relative to what they might have been in 1863. 

The reeds were tested for flip points at 70 degrees Fahrenheit when the tuning of the 4′ Octave was 434 Hz. The pipes were tuned on the wire sharp to their overblowing octaves, then tuned down carefully to their flip points, and the pitch of the pipe relative to A was measured on a Widener electronic tuner. The table below (Figure 27) shows the flip point frequencies for the Great reed chorus and Pedal Trombone.

16′ 8′ 4′ 2′ 1′

Gt 16′ 434.2 441.4 434.3 434.5 445.2

Gt 8′ 435 444.2 435.8 434.5

Gt 4′ 444.1 439.2 449

Pd 16′ 437 434.6 432.6

Pitch @ 70° 434 434 434 434 434

Figure 27

When looking at this table we need to bear in mind that the flip point frequencies need to be higher than the relative pitch of A to which we want to tune the chorus, i.e., these flip points should be significantly higher than 434 Hz. What we find are values ranging from 432.6 Hz to 449 Hz. The direct inference, assuming that the pipes have not been otherwise modified, is that the original chorus was significantly brighter than what we now hear. The dead length reed resonators were apparently not shortened and their tuning wires were used to achieve A=435 Hz, pushing many of the pipes very close to, or even beyond, their flip points. This is a significant offset in the flip point from the original voicing. It is clear that as beautiful and inspiring as it is, we hear a darker approximation of the original 1863 reed chorus in the present organ.

The magnitude of the deficit

The issue of pitch is complicated. Figure 28 shows a graphic depiction of the problem. The shift in pitch at middle A from 450 to 435 Hz is a change of 15 Hz. The distance between a half step at this pitch is about 25 Hz, and when the pipes were moved up a half step, middle A was then repitched to about 425 Hz. The 10 Hz deficit between 425 and 435 Hz was corrected by retuning the pipes. In the case of the dead length reeds, the tuning wires were simply pushed down to raise the pitch, so we know that the original Hook pipes in the table in Figure 27 would have “flipped” at frequencies about 10 Hz higher (at middle A) than what we measured in the table. To bring the pipes back to their original timbre at the current 435 Hz, the resonators would need to be shortened on all reed pipes by an amount that would produce about a 10 Hz increase in pitch at middle A. This may be inadvisable as it would reduce the scale of the resonators.

The Pedal Trombone was not moved up a half step, but large flaps of wood were added to drop its pitch from 450 to 435 Hz, covering the tops of its resonators and reducing its power and brilliance (Figure 23). The correction would entail the removal of the flaps and a lengthening of the resonators, which may be also inadvisable, as it would increase the scale of the pipes, an effect opposite to the correction needed for the reed chorus pipes of the Great division. 

The flue pipes suffered a similar fate and were retuned 10 Hz higher by one or both of two methods: making the pipes shorter and/or opening their toes. Of the two methods, the opening of the toes had a major effect on the timbre and power of the pipes. The impact of such changes is described in the notes on the 16′ Open Diapason and the 8′ Open Diapason Forte, with the result that the current balances deviate markedly from the original intentions of the Hooks. The correction would entail a reduction of the toes where they were opened, and a further shortening of the pipes. Since nearly all façade pipes have had their scrolls rolled down to the maximum extent, or even removed, the correction would require deeper cutouts and new scrolls on all pipes, not a simple or necessarily desirable proposition.

Raising the pitch from 435 to 440 Hz would push some reeds beyond the flip point, further darkening the sound, and it would increase the tuning deficit to 15 Hz. Such an increase in pitch would require further deepening of the façade pipe scroll openings, most of which are already at their limit. Further opening of the toes of the façade pipes would make their timbre and power even more imbalanced than their current state. All of these reasons suggest why the organ was never repitched to 440 Hz. 

Reflections

The Hook organ was put back into regular service use during the tenure of Fr. Thomas Carroll, SJ, as the director of the Jesuit Urban Center at the Church of the Immaculate Conception. Many notable organists at that time visited the church and played the instrument in concerts that were warmly and appreciatively received. 

It is hoped that the research presented in this study will inform those who restore this organ at a future date. Virtually all of the tonal modifications made to this organ resulted from the change to its pitch and the addition of the Solo division; the rest is vintage and very well preserved E. & G. G. Hook. 

Serious consideration should be given to the relocation of the Solo division in a manner that does not encroach upon the tuning of the original Hook pipes or limit the sound egress of the original Hook layout. The raw data indicate that the 1902 installation of the Solo division had a major impact on both counts. If the decision is made to remove the 1902 Solo division from the organ, and that conclusion should not be reached lightly, it should be carefully crated and stored, not discarded. It is a part of the Romantic tapestry and history of this organ.

Three possibilities now suggest themselves: 

1) Leave the organ at 435 Hz and reposition the Solo division to allow sufficient clearance to the Great and Pedal bass pipes. This preserves the current sound but corrects for the tonal and mechanical damage inflicted by the Solo division installation. It does not address the darker character of the reed chorus or the tonal imbalances of the 16′ and 8′ Open Diapasons.

2) Same as Option 1, but shorten the manual reed resonators to their original flip points, i.e., about 10 Hz shorter at middle A. Lengthen the wooden resonators of the Pedal Trombone and remove the obstructing boards. Restore the toes of the Diapasons to their original values and further deepen the tuning slots of all façade pipes. This involves significant expense in pipework restoration, it comes closer to the original Hook sound and power balances, but it permanently and perhaps inadvisedly changes the diameter scales of the many reeds that are cut to length.

Note that most of the scrolls on the reed pipes in Figure 29 (see page 22) are excessively rolled down in an effort to achieve 435 Hz; restoring the original pitch would correct this, so . . .

3) Repitch the organ to its original 450 Hz and move the pipes back to their original positions and voicing, restore the toes of the two Diapasons back to their original values, and restore the tuning scrolls of all pipes back to their original positions. This restores the original sound of the Hook. Repositioning of the Solo division is still essential.

Option 3 would not be the exact sound familiar to those of us who have heard the organ at Immaculate Conception, but it would be faithful to the original intent of the Hooks. The reed chorus would come alive. The author strongly recommends Options 1 or 3 over Option 2. Repitched to 450 Hz, the organ will not be compatible with orchestral instruments tuned to 440 Hz, but neither is the present organ compatible at 435 Hz, and the pipework will clearly not support 440 Hz. The argument can be made that we have a great many organs tuned to 440 Hz in our concert halls, while we have very few large Hook organs in their original state designed for superb acoustics like those of Immaculate Conception. Hook Opus 322 presents us with a unique challenge: it has been passed down to us in superb condition by the careful attention of the Lahaise family, and it may be the best opportunity we have to hear a large, well-preserved Hook chorus of Civil War vintage designed for a stunning acoustic.

The importance of the choice we make of the restoration options pales in comparison to the decision of the site of the organ’s new home. Much of this organ’s fame was the result of its placement in the stunning acoustics of the Church of the Immaculate Conception. When selecting or building a new acoustic for this organ it is important to realize that architects are not accustomed to the requirements of pipe organs. Be especially aware that definitions of reverberation by architects will not even remotely correlate with your musical perception of those acoustics. See The Sound of Pipe Organs, p. 32, for a detailed discussion of this ubiquitous problem. If the Church of the Immaculate Conception still exists in its original acoustical form, an unlikely event, take the architects there and make the accurate replication of those acoustics a requirement. If that acoustic doesn’t exist, take the architects to the Duke University Chapel in Durham, North Carolina. Architects will know how to measure it, but they will be stunned by the request to replicate it. The fame of the Hook organ and its original acoustical environment are inseparable. As any organbuilder will tell you, the best stop in any organ is the room in which it is placed, or to put it more bluntly, a wonderful organ placed in a mediocre room will sound­—mediocre.

Professor Thomas Murray, Yale University organist, has been deeply involved with this Hook organ, has made recordings of it (listed in the discography), and possesses a deep knowledge of the Romantic literature. Future restorers of this organ could benefit from his advice. 

We are incredibly fortunate to have at least some detailed data on the Hook organ, and we owe the Jesuit community and especially Fr. Thomas Carroll, SJ, a great debt for the opportunity to acquire it. Fr. Carroll now resides at the Collegio Bellarmino in Rome, Italy, a home to a community of more than 70 Jesuits representing more than 35 countries. He is the spiritual director for many of the Jesuits pursuing advanced theological degrees, conversing with about half in English and half in Italian. He provides guidance for young Jesuit scholars in the preparation of theses written in English, and for whom English may be a second, third, or fourth language.

Notes and Credits

All photographs, tables, graphs, and data are by the author except as noted.

1. Owen, Barbara. “A Landmark within a Landmark: The 1863 Hook Organ,” undated typescript.

2. Excel files with all raw data taken on the Hook and the spreadsheets that produced the graphs and tables may be obtained at no charge by e-mailing the author at: [email protected].

3. McNeil, Michael. The Sound of Pipe Organs, CC&A, Mead, 2012, 191 pp., Amazon.com.

4. Huntington, Scot L., Barbara Owen, Stephen L. Pinel, Martin R. Walsh, Johnson Organs 1844–1898, OHS Press, Richmond, Virginia, pp. 17–18.

5. Elsworth, John Van Varick. The Johnson Organs, The Boston Organ Club Chapter of the Organ Historical Society, Harrisville, New Hampshire, 1984, p. 45.

6. Noack, Fritz. Preliminary Report about the Pipework of the 1863 E. & G. G. Hook Organ, July 9, 1999.

Discography

Murray, Thomas. The E. & G. G. Hook Organ, Immaculate Conception Church, Boston, Sheffield Town Hall Records, Album S-11 (ACM149STA-B), Santa Barbara, CA.

Murray, Thomas. An American Masterpiece, CD, AFKA SK-507.

Useful References

Cabourdin, Yves, and Pierre Chéron. L’Orgue de Jean-Esprit et Joseph Isnard dans la Basilique de la Madeleine à Saint-Maximin, ARCAM, Nice, France, 1991, 208 pp.

Huntington, Scot L., Barbara Owen, Stephen L. Pinel, Martin R. Walsh, Johnson Organs 1844–1898, The Princeton Academy of the Arts, Culture, and Society, Cranbury, New Jersey, 2015, 239 pp.

McNeil, Michael. The Sound of Pipe Organs, CC&A, Mead, 2012, 191pp, Amazon.com.

Owen, Barbara. The Organ in New England, The Sunbury Press, Raleigh, North Carolina, 1979, 629 pp.

Michael McNeil has designed, constructed, and researched pipe organs since 1973. He was also a research engineer in the disk drive industry with 27 patents. He has authored four hardbound books, among them The Sound of Pipe Organs, several e-publications, and many journal articles.

Preface

Good documentation of organs with enough pipe measurements to permit an analysis of both scaling and voicing is extremely rare. Pipe diameters, mouth widths, and mouth heights (cutups) may be sometimes found, but toe diameters and especially flueway depths are rare. Rarer still are wind system data, allowing a full analysis of wind flow and wind dynamics, parameters that have an enormous impact on the sound of an organ. The reader will find all of this in the following essay on William A. Johnson’s Opus 161.

Good documentation is important for several reasons. We can make useful comparisons with other organs to learn how a specific sound is achieved. And perhaps most importantly, we can document the organ for posterity; while organs are consumed in wars and fires, they are most often replaced or modified with the changing tastes of time. They never survive restorations without changes. Comprehensive documentation may also serve to deter future interventions that intend to “modernize” an organ. Lastly, future restorations of important organs will be more historically accurate if they are based on good documentation.

The mid-nineteenth-century scaling and voicing of William A. Johnson is very similar to the late-eighteenth-century work of the English organbuilder Samuel Green, as evidenced by the data from Johnson’s Opus 16 and Opus 161. Stephen Bicknell provides us with detailed descriptions of Green’s work.¹ Johnson’s scaling is utterly unlike the work of E. & G. G. Hook, whose 1843 Opus 50 for the Methodist Church of Westfield, Massachusetts, set Johnson on a career in organbuilding when he helped the Hooks with its installation.² In this essay we will explore Johnson’s Opus 161 in detail and contrast it with the Opus 322 of the Hooks, both of which were constructed within a year of each other.³ While the Hooks used a Germanic constant scale in their pipe construction, Johnson significantly reduced the scale of his upperwork stops, much in the manner of Samuel Green and classical French builders.

The question arises as to whether Johnson came to his design theory by way of a process of convergent evolution (i.e., independently), or whether he was exposed to the organ Samuel Green shipped to the Battle Square Church in Boston in 1792, and which “was played virtually unaltered for a century,” according to Barbara Owen.⁴ The author suggested to Owen that the Green organ may have had a strong influence on Johnson, but she thought it unlikely that Johnson would have made the long trip from Westfield, far to the west of Boston. 

Travel would indeed have been much more difficult in 1843 when Johnson was exposed to the Hook organ at Westfield. But of some significance was the extension of the Western Railroad from Boston to Westfield in 1843. This new railroad may have been the means by which the Hook organ was shipped to Westfield. Elsworth (see endnote 2) clearly makes the case that Johnson was intoxicated by organbuilding with his exposure to the Hook organ. It is easy to imagine that he would have made a pilgrimage to Boston, at the time a mecca of American organbuilding, perhaps invited by the Hooks to accompany them after finishing their installation in Westfield.⁵

The author was engaged in 1976 by Mrs. Gene Davis, the organist of the Piru Community United Methodist Church, to evaluate the organ at that church. The identity of the organ was in question as no nameplate was in evidence on the console, the organ was barely playable, and its sound was greatly muted by the crude placement of panels in front of the Great division to make it expressive by forcing its sound through the shades of the Swell division above it. An inspection showed that nearly all of the pipework was intact, and a contract was signed to restore the organ to playable condition. The organ was cleaned, the pipes repaired, the few missing pipes replaced, and much of the action repaired by Michael McNeil and David Sedlak.

The church office files produced an undated, typed document that stated: 

The pipe organ in the Methodist Church of Piru was built by William Johnson, of Westfield, Mass., in the early 1860s, making it probably the oldest operating pipe organ in California. It was a second-hand organ when transported by sailing ship 17,000 miles around Cape Horn before 1900, and installed in a Roman Catholic Church in San Francisco. After the earthquake and fire of 1906, the organ was moved to another church and probably at this time parts damaged in the quake were replaced. After many more years of service it was retired and put into storage until, in 1935, Mr. Hugh Warring was persuaded to purchase it for the Piru church. It was purchased for the storage cost of $280.

Evidence of a different and more likely provenance was discovered during the removal of pipework and the cleaning of the organ. Three labels were found glued to the bottom of the reservoir (perhaps as patches for leaks). Two labels read: “Geo. Putnam ‘Janitor’ Stockton California July 1 ’99.” A third label read: “From the Periodical Department, Presbyterian Board of Publication, and Sabbath = Schoolwork, Witherspoon Bldg, 1319 Walnut St., Phila. PA.” At a much later time Reverend Thomas Carroll, SJ, noticed that the clues of Stockton, California, and the Presbyterian church correlated to an entry in the opus list of Johnson organs, compiled in Elsworth’s 1984 book, The Johnson Organs. Opus 161 was shipped in 1864 to the “Presbyterian Church, Stockton, Cal. The church is Eastside Presbyterian.” The organ was listed as having two manuals and 22 stops.⁶ At this time such features as couplers and tremulants were counted as “stops,” and this roughly fit the description of the Piru organ. The façade of the Piru organ is also consistent with the architecture of organs built by Johnson in the 1864 time frame. Elsworth’s illustrations include a console layout of Opus 200 (1866) virtually identical to the Piru organ layout; Opus 134 (1862) exhibits the impost, stiles, and Gothic ornamentation of the Piru organ; Opus 183 (1865) has similar pipe flats and also the console layout of the Piru organ.⁷ Many other details verified the Johnson pedigree, among them the inscription “H. T. Levi” on the reed pipes. Barbara Owen pointed out that Levi was Johnson’s reed voicer during the time of manufacture of Opus 161.⁸ The pieces of evidence fell together when Jim Lewis discovered a newspaper photo of Opus 161 in the Eastside Presbyterian Church of Stockton that matched the façade of the Piru organ. The most likely scenario is that Johnson shipped Opus 161 directly to that church. The Gothic architecture of the Johnson façade also reflects the architecture of the Eastside Presbyterian Church façade. A handwritten note on the Piru church document stated: “Pipe organ and art glass memorial windows dedication June 2, 1935 per Fillmore Herald May 31, 1935, a gift of Hugh Warring.”

It is possible that the organ went from the Presbyterian church into storage, and was later moved to its present location in the 1934–1935 time frame. Even so, we can say with nearly absolute certainty that this organ is William A. Johnson’s Opus 161.

Tonal design overview

It is obvious from even a casual glance at Elsworth’s study of Johnson organs that the Johnson tonal style was based on a classical principal chorus that included mixtures in all but the more modest instruments. But the voicing style is gentle and refined, and bears great similarity to the late-eighteenth-century English work of Samuel Green, whose meantone organ at Armitage in Staffordshire is an excellent surviving example.⁹ Tuned in meantone, Johnson Opus 161 would easily pass muster as the work of Green. The tonal contrast between Green and Hook is stark, and the Hook data serve as an excellent counterpoint to the data from the Johnson organ. Green was the organbuilder favored by the organizers of the Handel Commemoration Festival of 1784, who went so far as to have one of Green’s organs temporarily installed in Westminster Abbey for that occasion. King George III paid Samuel Green to build an organ for Saint George’s Chapel at Windsor.

Stephen Bicknell’s The History of the English Organ relates important details of Samuel Green’s work that we find in Johnson’s Opus 161. “. . . Green’s voicing broke new ground . . . . Delicacy was achieved partly by reducing the size of the pipe foot and by increasing the amount of nicking. The loss of grandeur in the chorus was made up for by increasing the scales of the extreme basses.”¹⁰ And “Where Snetzler provided a chorus of startling boldness and with all the open metal ranks of equal power, Green introduced refinement and delicacy and modified the power of the off-unison ranks to secure a new kind of blend.”¹¹ The Hooks, like Snetzler, used a constant scale where all of the pipes in the principal chorus at a given pitch had about the same scale and power.

The most basic data set for describing power balances and voicing must include, at a minimum, pipe diameters, widths of mouths, heights of mouths (“cutup”), diameters of foot toe holes, and depths of mouth flueways. The data in this essay are presented in normalized scales for inside pipe diameters, mouth widths, and mouth heights. Tables showing how raw data are converted into normalized scales may be found in the article on the E. & G. G. Hook Opus 322 published in The Diapason, July 2017. The full set of Johnson data and the Excel spreadsheet used to analyze them may be obtained at no charge by emailing the author.¹² Also available is the book The Sound of Pipe Organs, which describes in detail the theory and derivation of the models used in this essay.¹³

Pitch, wind pressure, and general notes

The current pitch of the Johnson and Hook organs is dissimilar and should be taken into consideration when observing the scaling charts. The Hook organ is now pitched at A=435.3 Hz at 74 degrees Fahrenheit, while the Johnson organ is now pitched at 440 Hz. The original pitch of the Hook organ was 450 Hz; new low C pipes were added when the pitch was changed to 435 Hz, and the original pipework was moved up a halftone, widening its scales by a halftone. The original pitch of the Johnson organ was approximately 450 Hz; the pipes were lengthened to achieve a lower pitch.¹⁴ The Hook and Johnson organs are both tuned in equal temperament. The wind pressure, water column, of the Hook is 76 mm (3 inches); the Johnson organ was measured at 76 mm static and 70 mm under full flow on the Great division. The pressure was reduced during the restoration to 63 mm static. This allowed the pitch of the pipes to drop, making the adjustment to 440 Hz with fewer changes to the pipe lengths; most of the pipes that were originally cut to length had been crudely pinched at the top to lower their pitch. With the reduction in pressure the ears of the 4′ Flute à Cheminée, with its soldered tops, achieved a more normal position. 

The Piru room acoustic was reasonably efficient, and while the Johnson voicing is very restrained, it was adequate to fill this room on the reduced pressure. The Piru church seats 109, has plastered walls, wood and carpet flooring, and a peaked ceiling about 30 feet high; the reverberation, empty, as heard with normal ears, is well under one second (this is not the measurement used by architects that erroneously reports much longer reverberation). Elsworth relates that “the wind pressure which Johnson used during this period was generally between 21⁄2 and 23⁄4 inches [63.5 and 70 mm], and, in rare examples, nearly 3 inches [76 mm].”¹⁵ The photograph of the original Eastside Presbyterian Church for which the Johnson was designed implies a larger acoustical space than that of the Piru church.

The compass of the Johnson organ is 56 notes in the manuals, C to g′′′, and 27 notes in the pedal, C to d′.

Stoplist

The Johnson console was found in poor condition, missing the builder’s nameplate and many of its stop knob faces. Correct stop names were derived from the markings on the pipes and the missing faces were replaced. The original stoplist is reconstructed as follows (Johnson did not use pitch designations):

GREAT

8′ Open Diapason

8′ Keraulophon

8′ Clarabella

4′ Principal

4′ Flute à Cheminée (TC)

22⁄3′ Twelfth

2′ Fifteenth

8′ Trumpet

SWELL

16′ Bourdon (TC)

8′ Open Diapason

8′ Stopped Diapason

8′ Viol d’Amour (TF)

4′ Principal

8′ Hautboy (TF)

Tremolo

PEDAL

16′ Double Open Diapason

Couplers

Great to Pedal

Swell to Pedal

Swell to Great

Blower signal

The above list adds up to 20 controls. The Johnson company opus list describes Opus 161 as having 22 “stops.” This may have reflected the original intention to supply the organ with stops having split basses, which are commonly found in Johnson specifications. The sliders for the Keraulophon and the Trumpet were found with separate bass sections from C to B, professionally screwed together with the sections from tenor C to d′′′. The two additional bass stops would account for a total of 22 “stops.” There are no extra holes in the stop jambs to indicate the deleted split bass stop actions. The extant stopjambs are apparently a later modification from the time of the installation at Piru or before. Elsworth noted that all Johnson organs of this period were constructed with square stop shanks.¹⁶ The current shanks are round where they pass through the stopjambs and are square where they connect to the stop action.

Several stop knobs were switched during the 1935 installation at Piru; e. g., the Viole d’Amour in the pre-restoration photo of the right jamb belongs in the position noted on the left jamb with the black plastic label “Bell Gamba,” which indeed is how this stop was constructed. The Swell Stopped Diapason was operated by a knob labeled “Principal” [sic]. The illustrations of the left stopjamb and right stopjamb diagrams provide the correct nomenclature as restored in the correct positions, with the incorrect 1935 nomenclature in parentheses ( ) and the correct pitches in brackets [ ].

The wind system

The wind system can be modeled from two viewpoints: the restriction of flow from the wind trunks, pallets, channels, and pipe toes; and the dynamics of the wind. Wind dynamics are fully explained in The Sound of Pipe Organs and are a very important aspect of an organ’s ability to sustain a fast tempo with stability or conversely to enhance the grand cadences of historic literature. The data set on the Johnson allows us to model all of these characteristics. Figure 1 shows the Johnson wind flow model.

In Figure 1 we see a table of the pipe toe diameters and their calculated areas; values in red font are calculations or interpolations from the data (e.g., wood pipe toes are difficult to measure when they have wooden wedges to restrict flow). These areas are measured for a single note in each octave of the compass.

A model for the total required wind flow of the full plenum of the organ assumes a maximum of ten pallets (a ten-fingered chord), as described in the table, and the flow is multiplied by the number of the pallets played for each octave in the compass. The sum of the toe areas of all ten manual pallets in the tutti is 5,057 mm². The total area of the manual wind trunks is 38,872 mm², and we see that the wind trunks afford 7.7 times more wind than the tutti requires, so much in fact that the trunks do not at all function as an effective resistance in the system.

Interestingly, the Isnard organ at St. Maximin, France, used the main wind trunk as a strong resistor to dampen Helmholtz resonances in the wind system, and that organ has ratios of wind trunk area to a plenum toe area of only 1.07 for the coupled principal chorus of the Grand-Orgue and Positif, but with no reeds, flutes, or mutations. Helmholtz resonances are the source of what is normally called wind shake, and we would expect some mild wind shake with the Johnson’s large wind ducts and low damping resistance. The author’s notes from 1976 state: “Very little sustained shake . . . a considerable fluctuation in pitch when playing moderately fast legato scales, which stabilizes very rapidly . . . this imparts a shimmer . . . .”

In Figure 1 we also see dimensions of the key channels, pallet openings, and the pallet pull length (estimated from the ratios in the action). These allow us to calculate the relative wind flow of the channels and pallets. We find that there are robust margins in wind flow from the channels to the pipe toes (244% at low C to 737% at high C on the Great). This accounts for the small drop in static pressure at 76 mm to a full flow pressure of 70 mm with all stops drawn. Pallet openings are less robust and flow about 100% of the channel area for the first three octaves and 190% in the high treble.

The underlying dynamics of a wind system are the result of the mass of its bellows plate and the volume of air in the system. These factors produce a natural resonance that can enhance the grand cadences of literature with a long surge in the wind, or it can produce a nervous shake if it is too fast. A grand surge in the wind is characterized by a resonant frequency of less than 2 Hz (cycles per second), and it is most often produced by a weighted bellows. A nervous shake results from a sprung bellows. We correct the latter condition with small concussion bellows in modern organs, but the Johnson organ does not have such devices; instead, it features only a large, weighted, double-rise bellows. 

We can model the dynamic response of an organ by using its wind pressure, the area of the bellows plates, and the combined internal volume of its bellows, wind trunks, and pallet boxes. The model in Figure 2 shows the dynamic response of the current Johnson wind system at a relaxed 1.61 Hz. This low resonant frequency drops further to 1.47 Hz when the pressure is raised to its original value of 76 mm. The author’s notes from 1976 state: “Light ‘give’ on full organ; relatively fast buildup to full flow.” That “light give” is the result of the low resonant frequency of the system. The resonant frequency of the Hook organ was modeled at 1.23 Hz, a value lower than the Johnson, and the Hook chorus does indeed exhibit a slower and grander surge on full organ. Figure 3 shows the modeled resonant frequency at the original pressure of 76 mm for the Johnson organ. The equation for modeling the resonant frequency of a wind system along with a worked example on the 1774 Isnard organ at St. Maximin may be found in The Sound of Pipe Organs, pages 99–113.

The wind system in pictures

See the accompanying pictures: Notebook sketch 1, Great windchest, Toeboard, Notebook sketch 2, Notebook sketch 3, Notebook sketch 4, Great pallet box, Pallet springs, Notebook sketch 5.

The layout in pictures

“Green’s organs stand on an independent building frame with the case erected around it, rather than being supported by the structure of the case itself.”¹⁷ Bicknell’s description of a Samuel Green organ applies equally well to this Johnson organ. The casework is built entirely of black walnut, a wood mentioned by Elsworth in reference to Johnson cases. The organ is situated within the front wall of the church. The original black walnut side panels (typical of early Johnson organs) were found crudely cut up and nailed behind the façade in an effort to make the whole organ expressive through the Swell shades. This had the effect of making the Great division sound like a diminutive Echo division. The typical layout of a Johnson organ is well described by Elsworth: “The framework was arranged to carry the chests of the Great organ and the supporting framework for the Swell, which was usually above the Great organ and slightly to the rear.”¹⁸ Such layouts, shown in Figure 4, are common in nineteenth-century American organbuilding. The walkway behind the Great allowed access to the pipes and pallets placed at the rear of that chest, and the rollerboard to the Swell division was normally placed just behind this walkway, allowing access to the Swell pallets that were placed at the front of the Swell windchest. Opus 161 was installed in an opening in the Piru church that was far too shallow to allow the depth of a rearward placement of the Swell division. 

As a result, there is evidence that the Swell windchest may have been reversed, placing its pallets to the back of the windchest, and the chest brought forward over the Great division. Note the lack of clearance between the 4′ Principal pipe and the bottom of the Swell chest in Figure 5. The internal framework shows signs of crude saw cuts; the order of the notes on the Swell chest is the same as the Great, but it is reversed; the Swell rollerboard appears to have been likewise reversed and now faces toward the walkway where the action and rollers are exposed to damage. 

To say that the Piru layout was cramped would be an understatement; no one weighing over 150 pounds would gain access to the pipes for tuning or to the action for adjustment without damaging the pipework or the key action. The author weighed less (at the time) and was barely able to navigate inside the organ. The current layout is shown in Figure 6. 

It is also possible that the current layout reflects the original layout by Johnson, but that the Swell was simply lowered to fit the height of the Piru church and brought forward to fit the limited depth available, reducing the depth of the walkway.

Notes and credits

All photos, drawings, tables, and illustrations are courtesy of the author’s collection if not otherwise noted. Most of the color photos were unfortunately taken by the author with an inferior camera in low resolution. David Sedlak used a high quality camera, lenses, and film to produce the high-resolution color photos of the church and its architectural details; these are all attributed to Sedlak.

1. Stephen Bicknell, The History of the English Organ, Cambridge University Press, 1996, Cambridge, pp. 185–187, 190–191, 207.

2. John Van Varick Elsworth, The Johnson Organs, The Boston Organ Club, 1984, Harrisville, p. 18.

3. A detailed study of the E. & G. G. Hook Opus 322 may be found in The Diapason, July, August, and September issues, 2017.

4. Barbara Owen, The Organ in New England, The Sunbury Press, 1979, Raleigh, pp. 18–19.

5. see: en.wikipedia.org/wiki/Boston_and_Albany_Railroad.

6. The Johnson Organs, p. 100.

7. Ibid, pp. 23, 50, 57, respectively.

8. The Organ in New England, p. 275.

9. 5 Organ Concertos, 1984, Archiv D 150066, Simon Preston, Trevor Pinnock, The English Concert.

10. The History of the English Organ, p. 185.

11. Ibid, p. 207.

12. McNeil, Michael. Johnson_161_170807, an Excel file containing all of the raw data and the models used to analyze the Johnson Opus 161, 2017, available by emailing the author at [email protected].

13. McNeil, Michael. The Sound of Pipe Organs, CC&A, Mead, 2012, 191 pp., Amazon.com.

14. The Organ in New England, p. 75.

15. The Johnson Organs, p. 25.

16. Ibid, p. 23.

17. The History of the English Organ, p. 187.

18. The Johnson Organs, p. 23.

To be continued.