Is there anybody going to listen to my story...?

[bcollins]

I tend to get long winded with my stories, and this one is a doozie, but I think it will be fun and educational. Especially for me. Hang on and you'll see what I mean.

As many of you know I've got a really big room, but lousy acoustics. I never shared with you (except some privately) what I did at Zion last spring to try to help the situation.

The choir loft was carpeted from wall to wall, and to make matters worse there was a tiered "pit" - if you will - for the bottom row of the choir. Back in the good old days when there was 30-40 people in the choir (before my time) this made sense. But now we're lucky to get 25 if in full-attendance.

Here's a picture of what it was like before. Note the heavily carpeted platform (blue) for the old upright piano.



Well, from time to time folks would trip up on the pit because it was hard to see the transitions. In fact one time an older fellow stumbled and almost fell over the railing - which was dreadfully lower than code. So I convinced the board of administrators that the pit should be raised to floor level and a new railing should be installed. They agreed and since I was spear-heading this little project I got things done the way I wanted them with very little resistance.

Here's a picture of the results with 120 square feet of 3/4" solid Vermont maple.



The church also got a newly restored 1937 Chickering out of the deal from another family that worked closely with me on the project.

Nice story? Wait, this is just background info. I'm just getting started. :)

[T.C.Lake]

Hello Bob,


Im listening -nice setup!

Terry Lake(UK)

[engrssc]

Say on, Bob. My gut tells me it gets better.

Rgds,
Ed

[bcollins]

Thank you Terry. Let's continue...

I haven't really been able to get an exact measure of what the improvement is. Sadly I didn't make reference recordings before and after. I can tell you that the choir can hear themselves better and it has made a cappella singing much easier.

As near as I can figure the improvement is at least 200ms additional decay time (measured across the room at the altar).

Here is a clip of the ending chord of an organ piece - organist is Walt Kroon - with a fairly full plenum - recorded before the wood floor and grand piano were added to the choir loft:

(you can click on the images for a higher resolution image)

And here is a 45 sec. excerpt of the recording:
http://zionorgan.com/HWForumImages/ZionAcousticsBefore.mp3
Decay time is estimated at 900-1000ms or just shy of 1 second.

Here is a clip of the ending of a different piece (unfortunately) - organist is James Tevenan - actually with less stops drawn than the previous recording, recorded after the hardwood and grand piano where added to the choir loft:

And here is a 45 sec. excerpt of the recording:
http://zionorgan.com/HWForumImages/ZionAcousticsAfter.mp3
Decay time is estimated at 1200ms or about 1.2 seconds.

This is all so very subjective though without proper reference recordings, but the difference - whatever it is exactly - is there.

Now, I've never been much for really big acoustics myself. Which is good because I'll never get this room up to 3-4 seconds. But about 2 seconds is what I like best.

My goal is to get as close to 2 seconds as possible, but short of removing all the carpet in the nave that probably isn't going to happen either. So I'll settle for somewhere between 1.5 to 2 seconds.

Next... what else can be done (without starting a war) and why bother?

[bcollins]

I recently came across this graph:


Now we all know how sound deadening carpet is. But what I really found interesting about this graph is that it shows exactly the problem at Zion. In a very large room that would otherwise be very reverberant were it not for carpeting, the bass notes still manage to reverberate but the treble notes do not.

So completely dry samples at 16ft and 8 ft pitch can be used, but not at higher frequencies. So when preparing samples for use at Zion in order to achieve greater realism slightly "wetter" samples must be used as we travel up the scale. And a slightly longer release tail must be used as well.

That is exactly the inverse of how Hauptwerk truncates reverb tails and I've asked Brett and Martin to make both options available in the future - at least in the CODM. BUT... that's not what this is about.

This is about exploring ways to improve the acoustics at Zion and why. It's obvious that carpet is our enemy. The challege is that carpeting on the chancel floor is best for the "contemporary" music people. And we must all try to get along, yes. If you try to remove the carpeting from the aisles you'll get a fight on your hands from folks who are afraid of slipping and falling during inclement weather.

Just for a point of reference here is a photo of the nave at Zion taken from the loft:


There are three areas in the nave that I think could be improved with minimal expense and without ruffling any feathers.

1.) The area behind the altar rail (technically refered to as the sanctuary) could be relieved of carpet.

The point of contact where the floor meets the wall and the plaster reredos is critical. The pastor agrees and since he, the cantor, and communion assistants are the only ones that ever go back there, we dont think anyone should mind.

2.) On the south wall there is a carpeted aisle.

There are also huge wood beams/posts. It stands to reason that the foot path is not between the beams, so the carpet could be pulled away from the wall 12" - the width of one tile - without obstructing people walking up and down the aisle.

3.) Above this aisle you'll notice a ledger. There is a matching one on the north wall as well. The ship-lap cedar on this surface is particularily dry and could be either re-surfaced or sealed without anyone but the choir even noticing.

---
Sorry this is starting slow, but I promise the plot really thickens...

[Lougheed]

I love a good story, especially with pictures. Do tell . . . !

[cknight]

I'm enjoying this, Bob. You're very much on the right track to be thinking about the absorption rates of different materials at various frequencies.

It's astounding how little acoustics are considered by some contemporary church designers. The original design for the building for which my project is destined called for a wide, fully carpeted room with suspended acoustic tile ceiling and very low side walls. Our acoustics consultant politely filled several pages explaining why the design was a loser. He drew a wonderful picture: "get 100 people spaced about 10 feet from each other outside on a windy day and sing". Faced with that, the principals accepted his recommendation and completely redesigned the sanctuary.

[engrssc]

Along the lines of improving the acoustics of a room for such as organ and choir music, as the space becomes more reverberant, likewise intelligibility of the sound reinforcement system becomes an issue. Even if acoustical feedback is not an issue (there are many means to limit such) a very live room, with it's longer tails, lends itself to this intelligibility problem. I notice the high center cluster which appears to be the sole sound reinforcement source which is excellent. I have been in a position that out of "necessity", we've had to place mulitple speaker systems down nearer to the ears of the audience to "help" alleviate some of this.

As a result of all of this, the spoken word suffered. Organ and other such music improved, tho. In a similar sized auditorium in Chicago, we had to install speakers every 10 feet along the side walls. Even with controlled delays to each speaker (set), the results were far less (realistic) than the original single cluster. When the auditorium was almost completely filled (rarely) the side speaker setup was a bit more "acceptable". But to my ears, again, not nearly as accoustically "believable/transparent" as the over head single point source. It was almost as if there was no reinforcement system in place originally.

In the initial survey,the chief archiitect suggested curved edges where the walls met the ceiling. (Ever witness the Mormon Tabernacle)? This was totally rejected by the "powers that be". Bottom line, there is a line between having good musical acoustics and human voice reinforcement.

Rgds,
Ed

[cknight]

The Zion interior appears roughly parabolic. I wonder what effect, positive or otherwise, that contributes to this acoustics exercise.

[bcollins]

I think positive. Unfortunately the entire thing is covered in unsealed cedar ship-lap siding. The expense of having the entire area sealed (the ceiling is 64 feet off the nave floor at the top peak) would be quite out of our budget. This is why I would like to concentrate on the tops of those ledgers (?). They are about 3 feet wide and [guessing] 55 feet long. The difference in finish would never be noticed by anyone in the pews.

[virtual-pipes]

My guess is that if somehow you got some or most of the carpet removed, you would wind up with a tubby, bottom heavy sound. Looks like your biggest trouble is the wood paneling on the walls. It would need to be sanded smooth, polished and sealed. It would still look great but wouldn't absorb most all the mids and highs. But, is there is any space behind the wood paneling, its going to act like a bass absorber. Its got to be stiff inorder to reflect lows.

[bcollins]

Robert,

On the north side (right) there is a catwalk behind the wall that runs the length of the building. I think there is also one on the south. I'll have to check the blueprints (which we have in the basement).

There is also a catwalk that runs above the peak. That's how we drop mics, maintain the ceiling fans, etc.

[bcollins]

Anyway... back to my little novella.

Enough about acoustics for a bit. Let's talk about why (besides the obvious). I can answer that in a word... Skinner.

I have the Masterworks E.M. Skinner set. I probably wouldn't have bought it but I needed it so I have it. I've never tried it at Zion because I never figured it would work - being so dang dry. But I've been racking my brain for months trying to figure out how I could make it work.

This is the root of what all this discussion was about in a previous thread here: http://forum.hauptwerk.com/viewtopi ... ght=#27459

Remember that the speakers all fire directly into the room. They are either on the back wall or right behind the grillwork shown here:

and shown from behind the grillwork, here:


What I have decided - besides some minor carpet removal in the nave - is to raise the ceiling in the organ chamber by at least 5 feet. There's nothing above this room except a big void that goes up clear to the peak of the building.

This will make the room 15 feet wide, 7 feet deep, 13 feet high at the back wall, and 17 feet high at the wall with the sound opening into the nave.

By doing so, I can increase the size of the sound opening to 12 feet wide by 8 feet high.

The wall treatment in the organ chamber now is 1-1/4" thick hard plaster. I can give the addition any treatment I deem to be in the best interest of the organ - plaster, hardwood, masonite, whatever.

The idea is to get the speakers in the chamber, firing up at the slanted ceiling - and add a bit of reverberation and pipe mixing before the sound escapes into the room.

Additionally, I am planning to upgrade from 16 channels / 20 amps to 24 channels plus 2 subwoofers. That's a whole nother story

Would I go to all this trouble and risk just to be able to use the Skinner?
Probably not. But there are still a few chapters to come.

[bcollins]

My guess is that if somehow you got some or most of the carpet removed, you would wind up with a tubby, bottom heavy sound.

Let's remember that word "tubby" for future converstation.

Allow me to ramble for a bit...

In this town there are about three outstanding [classical] organs:

The 1960 Aeolian-Skinner at St. John's Cathedral (post Harrison)
The 1997 Zimmer and Sons at St. Mark's Lutheran
The 1999 Pasi (tracker) at St. Augustine's Catholic parish

After that there are a couple of very respectable Balcom & Vaughn, and a 1966 Aeolian-Skinner / 1998 Balcom & Vaughn

I'd like to think our Hauptwerk organ falls somewhere after those six - real - pipe organs. Or maybe down the line a bit more with a few small respectable local "microbrew" trackers - but definitely before the host of old poorly maintained Estey, Kimball, and what have you. And definitely before the pipe organ at the Catholic cathedral downtown that Allen got there hands on and added 70 "digital" ranks to.

[bcollins]

OK... Ready for the plot twist?

I'm always on the lookout for a drawknob console. A little while back I was sent an email about a console that is available right here in town. I called the number, and after several attempts I talked to the owner of the console. Turns out he not only has the console, but almost the entire pipe organ as well – in storage – here in town.

The organ is a Wicks. But not just any Wicks. It is Wicks opus 3237, originally installed at University Presbyterian near the University of Washington in Seattle in about 1956(?). It is a 4-manual, 6-Division console with about 105 drawknobs and numerous tablet rockers for every conceivable inter/intra manual coupler.

I believe (judging from the time period and the original spec. here http://zionorgan.com/HWForumImages/3237Spec.pdf that it was pre neo-baroque "American Classic". Probably Wicks version of an A. Skinner style organ (a poor man's Skinner?).

The fellow (a Doctor) acquired the organ when it was replaced by a Reuter in 1999 (apparently the largest Reuter ever built). It was his intention to give the organ to his church here in Spokane when they built a new sanctuary. But time went on and the church decided to build a new gymnasium instead. Ouch!

I know this church – it’s another Lutheran church across town. The focus there is on youth and young families and “contemporary” music has been much more prevalent there for many years, so it shocked me a bit to hear that his dream was to install this organ there.

Anyway, as I said, time marches on and this organ has been in storage now for over 10 years. But here’s the catch: the organ was stored in three locations and one of those locations burned to the ground.

Lost was most every pipe over 7 feet, the entire Bombarde, all the chests, and all the swell shades, blowers, wood towers, etc.

I spoke about this organ and the console at great length with RonCrowl at Wicks. I was interested in the console as salvage (for the drawknob assemblies mostly) since it's way too much organ for our building. He assured me that all the drawknobs and rockers are electric solenoid, and should clean up and be trouble free "forever".
(Ron was kind enough to scan the original documentation at Wicks to PDF and send it to me)

At the time I really wasn't giving the pipework much thought. But ever since then something has been nawing at me. I cannot - after all these months since I first heard about this - get the image out of my mind of all those pipes sitting in crates for the last ten years right here in Spokane.

So here is a spreadsheet I put together which shows what pipes were lost and what pipes remain. He also sent me the 'Fire Loss Report' that was submitted to Wicks for insurance purposes.

“x” for existing pipes, “o” for lost pipes. It helps me to visualize what is still available.

http://zionorgan.com/HWForumImages/Wicks%20pipework.pdf

I'll bet you can begin to see where this is going now!