Have You Forgotten Your Password or Username?

**rjsilva** · 08-09-2019, 08:28 AM

I actually compared my SVS 16-46 PC+ (older cylinder model) with the Walker Quaker at my church. You can see the thread here:

https://organforum.com/forums/forum/...-walker-quaker

The SVS clearly produced 16hz at the same level as the Walker Quaker, though the hefty 15” driver in the Quaker could have handled more while the SVS was nearly max'd out in excursion.

I'm not sure how well a single SVS sub would do in a church setting with regular playing, but it has no issues playing organ CD's at home for extended periods at room shaking volumes (with massive excursion). Two of the SVS cylinders would probably ease the burden enough at my own church to not have to worry about pushing them too hard. But then two SVS subs probably cost more than a Walker Quaker and so there's little point in going that route.

In any case, an SVS sub capable of doing 16hz
in a church setting isn't going to be 9” in any dimension :)

**toodles** · 08-09-2019, 09:05 AM

Bass horn speakers can be built, of course, but the size required for low frequency response becomes enormous, so they are not common in the infrasonic range, nor really very practical for extremely low bass. The Klipschorn speaker is a commercially available bass horn of some notoriety. It is intended to sit in front of a 90 degree corner in a room, and the "mouth" of the horn ( the area that speaks into the room) is actually a few feet in front of the speaker cabinet--the adjacent walls form the last part of the horn enclosure. But even with its rather large size, the theoretical cutoff frequency is around 40 Hz, if I remember correctly.

You might be interested in a transmission line (TL) speaker, which is a different animal from the folded horn speaker. It uses an audio path for the rear wavelength of the speaker that is 1/4 of the wavelength of the lowest frequency to bring the rear wave back into phase with the front wave. That audio path can be folded to achieve an overall cabinet geometry that fits the available space.Here's an article on one such design: https://www.audioxpress.com/article/the-hideaway-tl-sub

One of the issues with a TL system is that at higher frequencies, the rear wave goes in and out of phase with the front wave as frequency rises--producing what is often called a "comb filter" effect. This is ameliorated by dampening the rear audio line so that higher fequencies are absorbed.

Another option might be a true infinite baffle speaker, where the rear wave is completely isolated from the front wave by a wall, ceiling, or floor. Essentially, this approach eliminates the cabinet,--an adjacent room becomes the cabinet. Such systems are very effective but require a suitable building structure--i.e., adjacent spaces. A suitable driver would have realatively high Qts (0.6 or higher), very low Fs (resonant frequency, 20 Hz or below).

**jbird604** · 08-09-2019, 11:25 AM

Getting back to basics, you could use two sheets of very good quality 3/4" plywood as the front and back. If 7' is the limit for the height, cut them both off at that height, then you'll have two 7' x 4' panels. Cut two holes into one of them to accommodate two 15" high compliance drivers intended for sealed cabinets. I use the relatively inexpensive ones from the old MCM, now known as Newark.com and they cost less than $50 each for good quality rubber-surround drivers.

After cutting the holes and making sure the drivers fit, and getting the screw holes drilled, reinforce both panels with a few strips of 3/4" plywood about 2" wide. Use the one-foot piece you cut off the end of each one and cut it into 2" wide strips. Glue and screw these securely in several places to make the panels more rigid. These reinforcing ribs will be on the INSIDE of the box when assembled, since you are tight on space.

Now get another sheet of the same plywood and cut the four sides of the enclosure from it. Make the side pieces exactly 7" wide, and cut to the correct length to turn the two panels you have made up into a large flat wooden box. It will turn out exactly 7' tall, 4' wide, and 8.5" deep, just right for the space you have.

The internal volume of it will be almost exactly 19 cubit feet (if I did my math correctly), which is plenty of volume to allow the rubber-surround woofers to go down VERY low, possibly all the way to 16 Hz. Probably not "flat" down to 16 Hz, as we have all figured out that is probably impossible anyway. But the sound should be quite decent. Wire and mount the two drivers, and there you have it.

I have of course never built such a box, but I did build a pair of them on a similar plan a few years ago for a custom church installation. I used 3/4" plywood frames that were 4' tall and 2' wide and 1' deep (internal volume just shy of 8 cubic feet). I mounted a single 15" rubber-surround woofer in each box, which was sealed. Used 3/4" plywood panels for front and back. I had one diagonal brace screwed to the inside of each panel for stiffness.

No technical testing was done, of course, but the boxes fit neatly inside the shallow chambers the church had for organ speakers. And they did the job beautifully. We were replacing a set of Rodgers SW7.5 subs on this particular organ (remodeling of the church had made it impossible to use the 7.5 boxes because they were too deep and wide). These new home-made boxes were FAR superior to the old subs in terms of smoothness and "oomph." I'd say that there was more fundamental tone way down into the lower reaches of the 32' stops than there had been with the Rodgers subs.

So, I'd think that a pair of 15" rubber drivers in a 19 cubic foot box would do a bang-up job on 32' fundamentals, nearly all the way down.

**michaelhoddy** · 08-09-2019, 04:59 PM

The pro AV company I own is dealers for Danley Sound Labs (danleysoundlabs.com), who are the most prolific purveyors of tapped horn designs for pro audio. I'm a true believer in these things, and I HAVE hooked one up to my Allen ADC 5000's sub bass channel, where the results are quite impressive. The biggest distinctive of this design is that the very lowest frequencies are consistent in output and also absolutely defined and musical, not just woofy bass output. Probably for practical purposes, but none of Danley's normal TH designs go below 30 Hz or a little above in usable response, so they don't do the bottom fundamental of the 32' octave really well.

Danley does make one sub, the DTS-10, that is -3 dB at 15 Hz, so probably great for organ. It's a mega home theater audiophile sub and huge and heavy though. Our company sold one to an audiophile enthusiast, but we delivered it only and never heard it in action. https://www.danleysoundlabs.com/prod...ty-subs/dts10/

When I was with Galanti, we worked with a custom speaker builder who built two transmission-line subwoofers for the pedal flue channels of the Chronicler III in St. John's Getty Square Yonkers, the organ on the Chronicler demo CD, which I helped install. Massive cabinets about 8' long, 3' or so high, and 18" deep, with the driver and port on one end. They crossed into separate speakers for the mid-highs. These were extremely impressive speakers, limited only by the capabilities of that organ itself.

**rjsilva** · 08-09-2019, 05:30 PM

It's maybe worth mentioning that Walker will make custom cabinet shapes for their B2000. I don't know if they would make one that is 9” in depth, and it'd probably be somewhat costly, but you'd be assured of excellent performance.

**Bach-On** · 08-09-2019, 09:16 PM

Thank you for your informed responses. Busy tonight. Let me study and respond later.

I will only say this. I have mentioned in the past that the bass response volume in our pipe/speaker chamber increases greatly when the doors are open. Some of that low stuff just isn't making it out through the opening into the Sanctuary.

John mentioned in another thread that a bass wave sounds very different from behind the console vs. what someone sitting on the bench may hear. That may be at play.

I don't know what the cause is, but the pedals aren't as satisfying as the other sounds.

BO

**Bach-On** · 08-10-2019, 05:53 AM

Let me touch on the SVS subwoofers for a moment. JBird mentioned that he compared an older SVS tubular bass speaker with the Walker Quaker bass. Correct me if I am wrong, but I believe both of those systems are now considered old. I'm the first to agree that new is NOT ALWAYS better. But sometimes it is. Digital Signal Processing has made it possible to shape many aspects of the sound pipeline of music out to the air for us to hear as we are able. Too, the source of the actual digital voices has seen improvement as the technology has been applied to the purpose.

Most would agree that - with the proper install - organs of the last decade sound more authentic than those of the 1970s and 80s. There are exceptions, or course.

Let me go on and say this. I am certain the organ at our church would sound better if we had the Walker system. I'm also certain the organ at my church would not have the extra voices we have now if we had to come up with the money for a new Walker system install. The Artisan system was a compromise. I will tell you a dirty secret I have learned. Some of the Walker samples that are so highly prized for their quality were done by the same people who did the Artisan samples.

I would not have been a good steward of the limited resources of my church to spend down the majority of their organ fund for the Walker system. It might sound better TO ME and one or two other members. But if most of our folks can't tell the difference, is it going to be worth the difference enough for them to come up with new money? Remember that over half the members of my church now attend a Praise and Worship service that makes no use of the organ.

Those who have followed the development of our hybrid system from when I first began asking question right here back in 2013 know we didn't have all that fine a pipe organ in the first place. We beefed up the console control system. The church should have replaced the console with an AGO console when the organ was refurbished back in 2000. Some held a reverence for the older console. To them it would have seemed like selling Grandmothers fine (aka: old) china.

We went with older Allen speakers. I drove 1,600 miles to go and get them. I had to refurbish the surrounds on the HC12s we bought. And I used what I felt were good plans and pretty good quality construction to make the big bass speakers for our system. That was yet another compromise to save money. WE COMPROMISED ON THE SPEAKER SYSTEM. And we compromised on the Artisan system. Otherwise, I'd still be playing a very limited dinky organ made up from parts of three old theater organs first installed in 1928 when there was no electricity in the building. (I played for the funeral of a 100 year old man who grew up in this church. He told me about being one of the boys who would go into the basement to pump the organ.)

Most of the folks who frequent this site are familiar with the pressure to compromise because of money.

The SVS systems have evolved. And the cost has not gone down due to mass production. Spending $3 or $4 thousand for a subwoofer would seem like a sacrilege to some?

And spending double that to get two of those suckers would probably seem like an outright sin worthy of decades in Purgatory or Hell.

But I've heard some of the newer SVS speakers. I just haven't heard them integrated into our organ. Could they overcome the loss of volume of the bass we seem to have built into our situation?

Example: I bought that older Allen B-40. Some have had great results with those. Some can get 16 Hz. out of theirs. I had OK results with ours, but ours cannot quite do 16 Hz.. It is pretty big. And one of the newer SVS subwoofers would fit in the space currently occupied by that B-40. My biggest concern is the sympathetic vibrations. Did I mention that that B-40 sits less than three feet from the opening of our organ out to the Sanctuary?

What I think some might have a tendency to do is fall back on what we know and what we have done. And I am right in there with that mode of operations.

I mentioned that I have a certain space, for example. I wondered if I could build, buy, install, etc. something there. The answer may be a resounding NO. Of, there might be some innovative way to do it that none of us have tried.

Do you guys see what I'm driving at?

If I'm being silly or unintentionally insulting, sing it out and say so. I won't go away, but I'll change the subject and work on it by myself. But I enjoy collaboration.

Bach-On

P.S, BTW I mentioned that a 9 inch cabinet width was a limitation within a particular space in our pipe chamber. But most bodies are thicker in the first four feet to five up from the floor. That's where I can't spare much width to create a bottleneck in that path into the pipe chamber. But get above my shoulders and the allowable width could be more. Is there some sort of subwoofer design that could work within those limitations? If I turned that older SVS tubular subwoofer JBird tested on its side, could it be made to fit if it was positioned closer towards the ceiling of the pipe chamber?

**Bach-On** · 08-10-2019, 06:37 AM

So - ignore the price for a moment. (Ha Ha). JBird - you'd need several expensive amulets to fight back the Voo Doo demons for this one. ;-)

Can that Walker Quaker Sub out do this one for lows?

https://www.svsound.com/products/pb16-ultra

The question for me is how will something like this blend with the total organ system? I'm interested in music - not the sound of an elephant stampede in the middle of an earthquake.

Too, how are they doing this? Can parts of it be replicated at a much lower price for personal use?

BO

**rjsilva** · 08-10-2019, 07:02 AM

I think perhaps you misunderstood my mention of the Walker Quaker and B2000. (On a side note, I have the B2 at my home and can verify it produces a strong 16hz although I don't know how it compares to the Quaker or B2000 under the same conditions.)

To clarify, I was only talking about Walker's speakers. They aren't as pricey as their sound modules and complete organs. I don't know the price of the Quaker subwoofer, but their 1103SD full range cabinets were around $200 the last time I checked (a few years ago).

As far as SVS cylinders, mine is an older model but SVS does produce newer models (PC-2000 $800 and PC-4000 $1800). The benefit of the newer PC-4000 would be a higher output.

Also, although not related to subwoofers but because you brought it up, in my own extensive testing with the Walker at my church, I observed that there are multiple separate components to their sound generationâ€”it's not as straightforward as sample playback (and may possibly have some elements of physical modelling). Meaning, it's not that someone made a good sample and they simply play it back.

**Admin** · 08-10-2019, 07:35 AM

Frankly, I don't understand the obsession with reproducing 16Hz. Most of the pipe organs I've played didn't have a 32' rank, and having one or more is certainly not a requisite for the vast majority of organ repertoire. It's certainly not necessary for the accompaniment of congregational singing. Then again, even if you have 32' foot ranks, getting down to 16Hz is not going to be required for reeds and strings which have little fundamental, and you can still benefit from the added gravitas of having a 32' flue even if the response of the last six notes or so is lacking.

Don't get me wrong, my comments are not intended to be critical of this pursuit, and if that's what floats your boat and you've got the budget and the room, go for it. For myself, I think focusing on improving the overall sound of the organ with more channels and speakers and making sure that the 16' voices are reproduced accurately and cleanly is where I'd put my effort.

**Bach-On** · 08-10-2019, 10:37 AM

When Sisyphus and I first started on this project, achieving the goal of playing 16 Hz. was not really on my bucket list. It has been on and off that list several times. I guess there is some of me that just wants to see if I can do it. You guys may recall that I live in the south. There's an old joke around my part of the country: "What's the last words of a Southern boy?" Answer: "Hey yall, watch this."

When I read a review of sub-woofers in some places - especially those for home theater - there are people who will describe places in movies with really L O W D O W N sounds. A sub-woofer is said to be able to reproduce those sounds well. That is often mentioned by some reviewers as a real positive. I mentioned the elephant stampede - to allude to that kind of thing. Most of the SVS subwoofers - the ones with ports - sometimes come with foam plugs that can be used to open, partially open or close those ports. Ports can sometimes extend the low range of a speaker. The trade-off is that they may do strange things to the frequency response curve at various points within the speaker's range.

The Artisan system allows me to alter the volume of each individual note of each individual stop. That is a blessing and a curse. Good control, but lots of variables to be changed if the stop is changed to another one.

I often have questions. That's the easy part. Answers can also be easy. Correct answers aren't always as easy.

My point is that understanding HOW a certain sub-woofer achieves something is interesting to me. IMHO Somebody said, "Hey yall, watch this." And then they did something unique. That is innovation.

BO

**toodles** · 08-10-2019, 11:13 AM

To get a driver that will perform at 16 Hz is quite simple--it requires a driver with a very low resonant frequency, which means a heavy cone. The SVS Driver in the PB16 has a fiberglass composite cone, which means it is very stiff and probably much heavier than your average subwoofer driver. The stiffness allows it to move at 16 Hz without bending so it pushes air instead of distorting the cone, and the heavy weight gives it a low resonant frequency.

The 8 inch voice coil (huge compared to almost any other speaker) lets it produce a large movement force while providing enough surface area to cool the voice coil so it doesn't burn out. The cabinet and port tuning then are worked out to get the low end response that this driver can inherently produce.

As mentioned before, there is no free lunch. The heavy cone makes the driver much less efficient than drivers with an average cone weight. The 1500 watt amplifier provides enough power to overcome the loss of efficiency. Low resonance and efficiency are always a trade-off.

**rjsilva** · 08-10-2019, 12:06 PM

As usual Toodles has a helpful technical perspective on these things. The driver in the Quaker is quite stiff but not as much as the PB16 Ultraâ€”from what I recall, it's actually very difficult to move the PB16's driver by hand.

For anyone who is amused by this stuff, I have a video of my Walker B2 doing 16hz at about 50W (normally I keep it around 15W which is more than enough).

http://files.rjsilva.com/organ/walker_B2_16hz.mov

And here's my SVS sub (13" driver) doing several 32' notes, the last held note is 16hz. It's probably using considerably more than 50W although its output is roughly similar to the B2 in the first video.

http://files.rjsilva.com/organ/svs_3..._demo_high.mov

It's surprising to me how much driver movement is necessary to produce these low frequencies at useful intensities.

**myorgan** · 08-10-2019, 02:49 PM

Bach-On,

Haven't we had this conversation before on the Forum the last time you were participating? I seem to remember you trying to fit a sub-woofer into pipe chambers back then, but didn't have enough room.

Is this an extension of that conversation or a new conversation? If it should be appended to the old thread, let me know.

Michael

Welcome To The Organ Forum

Have You Forgotten Your Password or Username?

How To Recover Your Username and Password

Ebay Classic organs

Announcement

Subwoofers

Subwoofers

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Hello!