Advice on subwoofer for virtual organ

[dmbendio]

I'm just setting up my virtual organ with Hauptwerk's St. Anne organ. I have two M-Audio EX66 speakers but no subwoofer yet. I am looking at either DefTech Supercube III (as recommended by Darryl Woods of MidiWorks) or SVS PB12NSD, neither of which I can hear locally. I do want to add another organ sample, with a 32' pedal stop, eventually, and want to be sure the subwoofer can handle that very low frequency without distortion. Most of the information I've found on subwoofers deals with home theater applications, rather than music, let alone pipe organ sounds. But some reviewers have thought the musical sounds at those very low frequencies (on some of the older, but larger Supercubes) left a lot to be desired.
Does anyone have experience with the SVS subwoofer? I'm not so concerned about huge volume as about clarity--and I do know that low of frequencies is more felt than heard.
(I'm considering these two subwoofers mainly because of value for my budget range--up to $800--and not too huge to fit in my family room/organ room.)

[dna]

Another subwoofer in the same price range is Hsu (http://www.hsuresearch.com/). I have the Velodyne 18" servo subwoofer, but that's more money. You might consider building your own subwoofer. It is much easier to build a good subwoofer than a full-range speaker.

[Stefanussen]

Hi, I was in the same boat as you a couple weeks ago. I was considering dropping lots of money on a Supercube III. Ended up getting a sub from Klipsch w/ 10" driver for $199 from Costco. Extremely happy with it. Great volume, still can make me sick to my stomach if I turn it up enough, and clarity is very good. Best part is that I didn't have to spend $6-800 for it.

BTW I'm in Salt Lake, if you're in the area, you're free to stop by to hear the sub.

[dna]

If that's the Synergy KSW-10, it spec'ed down to 29 Hz (- 3dB) which is fine for 16' but certainly not for 16 Hz of a 32' pipe that dmbendio wants.

[Stefanussen]

It is the KSW-10. Well, it may not have the right specs on paper, but my 32' principal and bombarde sound just fine :)

[dna]

It is a ported speaker which has to have a filter to prevent low frequencies below the port frequency from getting into the woofer which would otherwise over extend and destory itself.

You aren't hearing a 32' rank with that subwoofer, only the harmonics.

David

[Stefanussen]

You aren't hearing a 32' rank with that subwoofer, only the harmonics.

And some nice sounding harmonics at that! ;)

[Gert]

And what about the very cheap (About E 250,- in the Netherlands),
but with great specifications: Magnat Betasub 30 A?
http://www.redcoon.nl/index.php/cmd/sho ... ieskeurig/

# Principle: active 12" bassreflex subwoofer, downfire system
# Size (W x H x D): 335x510x400 mm
# Lower cut-off frequency: 20 Hz
# Upper cut-off frequency: 200 Hz
# Magnetically shielded: no
# Power output RMS: 130 Watt
# Max. power output: 260 Watt
# Switchable cut-off frequency: no
# Adjustable cut-off frequency: yes
# Cut-off frequency , low: 50 Hz
# Cut-off frequency , high: 200 Hz
# High level in: yes
# High level out: yes
# High level out HP: no
# Low level in: yes
# Low level out: no
# Low level out HP: no
# Switchable phase: yes
# Adjustable phase: no
# Bass Boost 1: 0
# Bass Boost 2: 0
# Power ON/OFF switch: yes
# Voltage Selector switch: yes
# Standby circuit: yes

Or this one: Yamaha YST-SW 515 (about E 270,-)
http://www.yamaha.co.jp/english/product ... sw515.html
# Inputs: Line in & Speaker in
# High Filter 40-140Hz
# Auto Standby
# Fase instelling (Normal or Reverse)
# Uitgangsvermogen 250 Watt
# Frequentiebreik 20-160Hz
# Power Consumption 80 Watt
# 25 cm Cone
# Magnetische afscherming
# Anti-skid pads

I have already 2 Genelec 8040A (48 Hz - 20 kHz, 2 x 90 W), so the SubWoofer is only for 20Hz - 50Hz.

Regards,
Gert

[dmbendio]

Thanks for the replies, but I REALLY want a sub that goes BELOW 20 Hz, as dna mentioned, down to 16 Hz for a 32' pipe. I'm not trying to get the cheapest deal, just the best audio at the low frequency end for what I can afford--without having to get a HUGE box.

I'm sure ANY subwoofer would sound great to begin with, since I don't have one at all right now, but I've found my ear gets more sensitive as I get used to better quality, so I want to start out picky! (Sorry, dna, but I DON'T want to build my own-no time or skills.)

Anyone with SVS and/or Supercube III (or maybe even II) experience? (Both of these are supposed to go to about 16 Hz.)

[ten87]

Thanks for the replies, but I REALLY want a sub that goes BELOW 20 Hz, as dna mentioned, down to 16 Hz for a 32' pipe. I'm not trying to get the cheapest deal, just the best audio at the low frequency end for what I can afford--without having to get a HUGE box.

When considering subs, just keep in mind there is this thing called Hoffman's Iron Law. Google it for a complete explanation, but here is a summary:

Hoffman's Iron Law: small, loud, low. Pick any two, you can't have all three.

If you want FLAT response to 16Hz, you'll need a LARGE box to do it. I'm sure the Super Cube series does indeed go to 16Hz, but I wouldn't doubt that the response starts dropping at about 30Hz. I have never seen a published response curve for any of the products on the Definitive site, which, IMHO, is points off for them. I've heard positive response from those who have used Definitive subs, so I'm not in any way trying to steer you away from them. Just don't expect a huge output at 16Hz unless you shell out $3k for a Trinity Super Cube! Most living rooms can't handle 120dB at 16Hz anyway, unless you screw the pictures to the wall!

The subs I will be building for an upcoming project will go flat to 20Hz and will be a 36x36x30 box. The project is still in the works, but I hope to develop and make available an economical but efficient sound system for use with virtual instruments that will have size/performance options. Most of the options out there are hugely overpriced for the performance you get.

Terry

[dna]

If you want FLAT response to 16Hz, you'll need a LARGE box to do it.

That's not entirely true. Flat frequency response can also be achieved by equalization, by servo control, or in the case of HW, by voicing. One might be tempted to say that in that case, the maximum output at lower frequencies would be compromised but this is not necessarily true either. A woofer of a given size and excursion in any enclosure that prevents back wave cancellation will produce the same amount of bass whether it is in a small or big box, or in a closed or ported box. Nor is it true that a larger enclosure results in lower distortion. In fact, it is more difficult to build a large box that is free of colorations than a small one.

What a large box does is make the driver more efficient since it doesn't have as much back pressure to fight. It takes more effort to move the cone in a small box than a large box. However, the same output in a small box can be achieved using higher amplifier power and a driver that can dissipate that power. This is the principle behind many higher end small subwoofers on the market today which have very high power amplifiers, sometimes more than 1 KW. A large enclosure can use a less expensive driver and lower power to achieve the same output. However, it can't produce any more power or deeper bass than a well designed small speaker of the same size and excursion because in both cases the maximum output will be limited by driver excursion.

-David

[Johannes Sørensen]

Another thing to take into consideration, before wee plan to buy or build a subwoofer and decide how low frequencies wee want it to reproduce, is the acoustics of our living room.
As a rule of thumb the length of the room must be at least the half of the wavelength of the lowest frequency that can be reproduced in the room.
To reproduce 32 Hz the length of the room must be at least roughly 5.5 meters and 16 Hz 10-11 meters.
In my room I am glad to hear the fundamentals of the lowest octave of the 16' stops.
Fundamentals of the lowest octave of 32' is outside the possibilities and my neighbours are glad so.

Regards
Johannes

[ten87]

This is the principle behind many higher end small subwoofers on the market today which have very high power amplifiers, sometimes more than 1 KW. A large enclosure can use a less expensive driver and lower power to achieve the same output. However, it can't produce any more power or deeper bass than a well designed small speaker of the same size and excursion because in both cases the maximum output will be limited by driver excursion.

I'm not a fan of huge excursion. Distortion is often a direct product of excursion. I do think a well designed box and driver yield a better result, but to me, a well designed horn sub running with 4mm excursion and ~100 watts of power sounds cleaner and faster than a direct radiator flailing about with 20mm excursion with 1200 watts. There are a lot of small direct radiator subs out there that would do fine, especially in a living room situation. I'll gladly give up a little space for the sound I want. That's just my preference. As they say, "results may vary."

Terry

[dna]

Good point, Terry. But a servo'ed subwoofer (like my Velodyne) has measurably lower distortion even at high excursions than a non-servo driver at low excursions. As far as a subwoofer being "fast", how fast does a driver need to be in the 16 Hz to 80 Hz range? Not very.

However, I'm not trying to talk anyone out of going the large enclosure subwoofer route if they have the room for it. I just wanted to point out that you can get a subwoofer with fairly flat frequency response down to 16 Hz in a moderately small box.

[ten87]

Good point, Terry. But a servo'ed subwoofer (like my Velodyne) has measurably lower distortion even at high excursions than a non-servo driver at low excursions. As far as a subwoofer being "fast", how fast does a driver need to be in the 16 Hz to 80 Hz range? Not very.

Agreed, in terms of organ sound reproduction. The driver will respond faster than a 32' pipe would. If you cross over at 80Hz, you might notice the faster driver, but extreme lows aren't an issue with organ music.

I have to admit I don't have any experience with servo'ed subs. I have worked with Bag End Infra Integrators and 18" drivers, which claim flat response to 8Hz. I'm not real impressed with the sound of these (they sound "boomy" to me), and hope to do an A/B comparison with a set of horn subs sometime soon.

Terry