Sub that ROCKS at 16Hz!

If low, accurate bass is what you are looking for, buy the plans and build yourself one (or two if you have a big room) of these:

http://www.billfitzmaurice.com/THT.html

I built two of these folded horns, 36" wide and stacked them on top of each other firing into the corner of one of the organ chambers. I wanted to wait until I had a chance to really put them through their paces before posting my impressions, and can honestly say they have exceeded my expectations! You could cause structural damage with these things if not careful! I had them turned up a little too loud when I was adjusting the crossover, and I had every metal stud in the ceiling rattling and walls shaking with the amp only putting out about 75 watts per channel (each cab on its own channel) The 15" drivers are rated for 350 watts. The amp is currently set on 3. At 36" cubed, they're big, but you can build them narrower (as little as 24" wide) to get through narrower doors. The wider the cab, up to 36", the flatter the response.

I have some pics of the project up on facebook at http://www.facebook.com/album.php?aid=2013365&id=1169361008&l=1015d40de1

So far I have 18 channels of audio running the Milan Skinner dry set through Hsu Research HC-1 speakers pointed up at the ceiling of the organ chambers, with the 2 THT's to carry the bass frequencies. 6 ranks of pipes will be coming online in the next 2 or 3 weeks, with the other 17 ranks coming online when I get the new chests built. More details as the project progresses.

Terry

Well done and even more. Couple questions/thoughts, it appears that the bench is adjustable height wise, what mechanism did you use?

Also, what thickness material is used for the subs? Would be curious as to how your subs would compare to http://www.decware.com/newsite/hwk15.htm

Was the console existing previously and then reworked? It appears that the manuals (section) plus the 2 draw knob assemblies are joined - making them as one piece? Wiring is very well done.

What is the makeup of the console's "umbilical" cord?

How many ranks are real vs virtual?

How much time has been "logged" so far? I'm always curious in the planning that goes into such an installation with regards to keeping the sanctuary in a useable condition.

Rgds,
Ed

Hi Terry,

I just decided today I need to do something about getting a subwoofer. I was planning once I get my floor done, to install an infinite baffle subwoofer using 4-15" drivers in the floor with the rear of the woofers firing into the basement. This I think would be the ultimate.

But after reading your posting I may try the Tuba. I had previously looked into the Housewrecker Ed mentions, but looking at various reviews of people that built them, it appears there's too much variable and that they generally don't produce the very deep bass very good. My biggest concern really is that there are just a few small ports for all of the sound to come through. Certainly not very conducive to good coupling to the air, unlike a folded horn as you mention.

Anyway, what driver did you use? I assume a Dayton from Parts Express? The dual voice coil version I've read is very close to the Tempest they mention.

I have a woodworking shop and space for the unit so a 3' cube is no issue.

Thanks,
Eric

WOW! Really exciting project!

Best wishes

David P

Well done and even more. Couple questions/thoughts, it appears that the bench is adjustable height wise, what mechanism did you use?

I made my own mechanism based on the Organ Supply adjustable bench that we had in the shop at the time. The adjustable mechanism is available from Organ Supply without the bench, but it is too big to fit in a "gate leg" bench. Also, it wasn't in the budget, so making it myself cost a lot less. It was a pain to build though.

Also, what thickness material is used for the subs? Would be curious as to how your subs would compare to http://www.decware.com/newsite/hwk15.htm

All of the cabs on the Bill Fitzmaurice site use 1/2" plywood, preferably baltic birch for its stiffness. They don't recommend MDF as it would make the cab ungodly heavy and isn't nearly as structurally durable. The 2 cabs I built took 7 4'X8' sheets of baltic birch plywood. That's 3 1/2 sheets per cab, plus the weight of the driver (1 per cab)

Was the console existing previously and then reworked? It appears that the manuals (section) plus the 2 draw knob assemblies are joined - making them as one piece? Wiring is very well done.

It is a reconditioned used console made by a local company in the 1940's. The keyboard stack and draw knob assemblies are separate in that all of the drawknob units (Syndyne) have plugs on them. The nameboard (above the keyboards) is attached to the relay panel and is attached to the keyboard stack (no plugs on the keyboards, so these parts stay together, but tilt up for easy access to the key contacts.) BTW the top two manuals and key cheeks are out of our old console. The bottom keyboard is a keyboard that was sold at the M.P. Moller auction when they went out of business in 1991 and is exactly like our original two keyboards! Control system is Artisan Micro Midi.

What is the makeup of the console's "umbilical" cord?

The cables within the console are standard telephone cable wrapped in spiral sleeving from McMaster-Carr http://www.mcmaster.com/#7432k731/=4ku75a The cable that goes out to the chamber is a single cat 5.

How many ranks are real vs virtual?

24 real, 33 virtual. Subject to change, of course.

How much time has been "logged" so far? I'm always curious in the planning that goes into such an installation with regards to keeping the sanctuary in a useable condition.

I have no idea how many hours I have in the project at this point, but I've been averaging 10 hours a week for the last year or so. It's no small project, but then, I do this for a living, so I knew that going in!

Terry

But after reading your posting I may try the Tuba. I had previously looked into the Housewrecker Ed mentions, but looking at various reviews of people that built them, it appears there's too much variable and that they generally don't produce the very deep bass very good. My biggest concern really is that there are just a few small ports for all of the sound to come through. Certainly not very conducive to good coupling to the air, unlike a folded horn as you mention.

Hi Eric,
I'm not a speaker builder, but did a lot of research on this before I made saw dust. Re: the Housewrecker, your concerns were mine as well, and that's one of the reasons I went with the Tuba HT. Very low distortion and high sensitivity of the THT were the clinchers. One driver in the THT vs. four in the Housewrecker also helped with the budget. Check out this video from a THT builder http://www.youtube.com/user/derekrreynolds#p/a/u/1/OIBdkXW_jns Lots of good information is on the Fitzmaurice forum as well. http://billfitzmaurice.info/forum/ Check out the Tuba and Titan Subwoofers and Home Theatre/Stereo/Auto Sound forums specifically.

Anyway, what driver did you use? I assume a Dayton from Parts Express? The dual voice coil version I've read is very close to the Tempest they mention.

I used the Dayton RSS390HF-4 15" Reference HF Subwoofer http://www.parts-express.com/pe/showdetl.cfm?Partnumber=295-468, but I would use the Dayton DVC385-88 15" DVC Series Subwoofer http://www.parts-express.com/pe/showdetl.cfm?Partnumber=295-190 if I had it to do over. The specs of the DVC are almost identical to the Tempest driver that the cab was designed for. The driver I used is an approved driver for the cab, though, so there probably isn't much difference. You're not too far away...if you want to come hear them before you build, just let me know!

How loud does a 32' Bourdon need to be, though? The Bombarde, on the other hand...

Terry

There's been some discussion(s) here recently regarding control, as in computer and amplifiers. Do you use a sequencer to control the power to the amplifiers?

What about the computer? Some have suggested putting the computer in the sleep mode when not in use. Concern over a SATA or SCSI hard drive running 24/7, or using a solid state SSD(s).

Does the CAT 5 c(from the console) include these control functions or merely organ MIDI etc functions? I would assume you have (console) power going along with the CAT 5 out to the console.

What roughly is the distance between the console and the (computer) main setup?

Rgds,
Ed

Well done and even more. Couple questions/thoughts, it appears that the bench is adjustable height wise, what mechanism did you use?

I used part of a bench I bought. Some photos are here. Happy to provide more info if needed. The mechanism (very sturdy!) and seat were less than $100 US, and were relatively easy to build into the bench.
http://www.fagerjord.org/orgel/gerken/index.html

Barry Gerken

There's been some discussion(s) here recently regarding control, as in computer and amplifiers. Do you use a sequencer to control the power to the amplifiers?

No, I use solid state relays to turn them on. There is a rack of amps in each of the two chambers, and each of those has a dedicated 20 amp outlet just for the audio. I mounted one of these http://www.mouser.com/ProductDetail/Crydom/D1240/?qs=sGAEpiMZZMtLEhJ5P%2fNsZ2U%252bOuJVYyt61S4F89zZ13I%3d in a J box in each of the chambers to turn the outlets on and off with the organ. The whole rack starts and shuts down at once with no problems.

What about the computer? Some have suggested putting the computer in the sleep mode when not in use. Concern over a SATA or SCSI hard drive running 24/7, or using a solid state SSD(s).Does the CAT 5 c(from the console) include these control functions or merely organ MIDI etc functions? I would assume you have (console) power going along with the CAT 5 out to the console.

The computer runs 24/7, but I will probably change that in the future. I will probably have the relay send midi to Hauptwerk to tell it to shut down the computer, then have a "one shot" relay "push" the power button on the computer to boot it when the organ turns on. The boot time is under a minute, so I don't think it would be too bad. The audio interface comes out of sleep mode just fine, but you can't trigger sleep mode from Hauptwerk, at least not yet.

The cat 5 cable does carry power, but only to trip the solid state relays that turn on the audio and throw the blower contactors. I'm using Artisan Midi Extenders to get the signal to the chambers. They send midi over cat 5 cable, then decode it at the other end. The extra wires in the cable send the signal to the audio and blower solid state relays.

Yes, there is 110 volts in the console to run the 5 volt and 12 volt power supplies, as well as music rack and pedal board lights.

What roughly is the distance between the console and the (computer) main setup?

It depends on which of the two jacks you plug the console into. Max distance is probably about 75', because the jack on the right side has to go up through the attic and down into the chamber on the other side.

Terry

The driver I used is an approved driver for the cab, though, so there probably isn't much difference. You're not too far away...if you want to come hear them before you build, just let me know!

Thanks for the info Terry. I'd love to come see your project and the speakers of course. I'll get back with you when I get a chance to see about making a trip down there.

Eric

Thanks for the info Terry. I'd love to come see your project and the speakers of course. I'll get back with you when I get a chance to see about making a trip down there.

Just let me know, and I'll make the arrangements.

Terry

Thanks for the info Terry. I'd love to come see your project and the speakers of course. I'll get back with you when I get a chance to see about making a trip down there.

Just let me know, and I'll make the arrangements.

Terry

Hi Terry,

I'm not sure when I'll be able to make it down, but in the meantime I've been thinking about building one of these beasts. Bill mentions panel jigs on his ordering info page. Did you get these? I know they don't cost much, but I'm not sure if they are of much benefit, or are particularly for a specific size, say 24" rather than 36".

Thanks,
Eric

How loud does a 32' Bourdon need to be, though? The Bombarde, on the other hand...

A reed won't have that much energy in the fundamental. But the answer to this question about loudness of a 32' Bourdon, or even a 32' Open Wood, would be most helpful as I am also working on 32' cabinets. The typical low-cost SPL meter doesn't work that low, but given the low sensitivity of human hearing in the deep bass region, I'm expecting a relatively high number. Does anyone know the answer?

I'm not sure when I'll be able to make it down, but in the meantime I've been thinking about building one of these beasts. Bill mentions panel jigs on his ordering info page. Did you get these? I know they don't cost much, but I'm not sure if they are of much benefit, or are particularly for a specific size, say 24" rather than 36".

I made the panel jig, but didn't use it at all for the THT. We have an excellent table saw at work that has a very accurate fence, and I found the panel jig unnecessary. I will be using it when I build the Fitzmaurice Jack speakers for the high power channels sometime next year.

The panel jig is useful when cross cutting large pieces.

Terry