How Many Subwoofers is Too Many? (1 Viewer)

[Phuong]

A few years ago, Tom Nousaine published a short research article in AUDIO magazine called "Two in the corner beats five in the round," basically stating that two subwoofers placed in the optimum corner are the max necessary to get smooth, flat bass response, and far superior alternative to locating 5 subwoofers at the L-C-R-S positions. Love him or hate him, the guy does his homework and has the numbers to back up his arguments. As far as I'm concerned, the man is a guru and always on point.
Peace, and happy listening.

 

[AaronNWilson]

If you place say a 12 inch sub directly below your speaker, your basically just turning that speaker into a full range tower. I don't see how this can be any different from people who use full range towers all around such as the Dunlavy SV IV.
I would say go for it if you have the money. You could place a paradigm PW 2200 sub below each speaker which I hear is a nice musical sub, then if you place a nice tower on top such as a B&W CDM NT then you blend the sub in perfectly with your crossover then you are going to have fantastic sound.
If you are only going to be using the subs to produce that channels bass then I dont think you should run into any problems. You could just stack a bunch of SVS Ultras in the corner for that serious LFE hit.
Aaron

 

[Patrick Sun]

You know you have too many subs when you turn on your system, play a LFE-loaded DVD, and you inexplicably whizz in your pants uncontrollably.
------------------
PatCave; HT Pix; Gear; DIY Mains; DIY CC; Sunosub I + II + III; DVDs; Link Removed

 

[BryanZ]

Jason,
I believe I have the answer to your question. The diameter of the current SVs is 16", so I will use that figure. Since your room is 12' * 14' that will equal 2,016" of floor space. Assuming you want the room stuffed with subs, we will allow you to have a more than generous 1,008" for yourself and your equipment. This leaves us with 1,008" for deep sonic bliss and foundation breaking bass. Given your circumstances and desire to bring the house down, I would recommend 16 SVS Super Series subs. It should cost a measly $40K. If that isn't enough subs for you, I do not know what is.

 

[ling_w]

This advocating as many subs as possible in the same corner is insane. Putting a sub in a corner is just the starting point in placement, not the final point. It is pretty much a no brainer approach to get the max dB out of the room and maybe not encounter dips in response. If people follow that blindly, then what's the point of fine tuning a system? If someone had a 9x9x9 room, and their seating position back against the rear wall, do we still tell them to put the sub in the corner?
Anyway, if you want to split LFE to multiple subs, then you might be able to put the subs in opposite corners to cancel out standing waves. Or you could put one 1/2 way along the length of the room, and the other one 1/2 way along with width. You have 2 subs now, it doesn't hurt to try these positions out.
As far as 1 sub for each channel, it might be preferable that you don't put each sub right under the speaker, it could be placed at a position near the speaker itself, but having a smoother bass response.

 

[John H]

My system is setup in a 2048 cu ft room.
I use Def Tech BP2000's for Mains each with a powered 15" subwoofer section.
I use a C/L/R 3000 for a Center speaker. The Center channels signal is passing through a Paradigm X-30 highpassed at 80Hz. The lowpass signals feed the subwoofer sections LFE low level inputs on each 2000. This bypasses the Mains internal filters. I do not use the 3000's 10" powered woofer section.
For Surrounds I use 2 pairs of BPVX's. I use a Paradigm PW-2200 on each channel. X-30's highpassed at 80Hz are used for these.
I use Avia to balance the upper and lower sections of all channels.
For the LFE/SUB channel I use a pair of Velodyne HGS-18's. An Audio Control PCA III subharmonic synthesizer is used on the signal. I calibrate the LFE channel to the same level as the others once subharmonics have been added.
I also use a pair of Buttkicker tactile transducers on the LFE/SUB channel. Another Audio Control PCA generates subharmonics 1 octave and a Behringer EX1200 generates subharmonics 2 octaves below the original. An X-30 lowpassed at 35Hz sums the 2 units output signals before feeding my power amplifiers.
I highpass all channels at 40Hz for movie material. For multichannel music I drive them full range and bypass the subharmonic synthesizers.
John
------------------
Link Removed

 

[Jason_S]

John, that's definitely a lot of subwoofin'. Two 12"s, two 15"s, and two 18"s. Wow!
I'm thinking a 12-incher for each of [eventually] seven speaker locations in addition to an SVS SS sub for LFE. It would be neat to do a 15-incher at each speaker, but with my room size, even I think that's way too much!

 

[Jason_S]

As I said earlier, I would like to put the speakers on top of each subwoofer. Would anti-vibrational devices such as Vibrapods prevent vibrations, from the sub enclosure, from affecting the speakers? In other words, would something like a sheet of MDF and some Vibrapods sandwiched between the sub and the speaker keep the speakers from vibrating off of the sub?

 

[Paul Ward]

I would recommend adding a few Tactile Transducers to the mix. I was wanting more bass and after adding one at each end of the couch I'm totally satisifed.
Paul

 

[Jason_S]

Does anyone know where I could find published articles on the Internet and/or more information on using a dedicated sub for each channel? (Preferably, I would like to hear from someone who has actually attempted the dedicated-sub approach.)

 

[Tom Vodhanel]

>>>Does anyone know where I could find published articles on the Internet and/or more information on using a dedicated sub for each channel? (Preferably, I would like to hear from someone who has actually attempted the dedicated-sub approach.)

 

[John Morris]

Hey folks... listen to TV!
I always do, unless it has to do with pricing...
I have tried and considered many different multiple sub combinations and I've found ONE to work best.
A single Ultra in my best corner.
Even when I upgrade my primary speakers to full range all the way around... I will still have that Ultra in the corner for LFE and sub 60 fill.
Believe me, due to the Ultras cleanness, I've considered a pair of stereo Ultras but my right front has no corner and when I tried it with a pair of 20-39cs subs, I suffered many worse room mode problems...
------------------
Take Care,
merc
----------------
Link Removed
God Bless America!!!

 

[Stephen Dodds]

I have what you are pondering. My mains are sitting on dedicated subs, plus I have subs for my rear/sides and I have a sub for LFE.
As TV mentioned, it is a bitch to setup and get right and I'm not convinced I have. I use EQ for each sub.
Every now and again I play with bass management and compare the setup to crossing over at 80Hz to one sub. I think my setup sounds better (music-wise) but it is damn close and I may be fooling myself because of the time and money I have invested.
For a movie-centrric setup I would certainly make life easier and use one sub.
Also, a room your size would pose real problems, I suspect.
Steve
------------------
Link Removed

 

[Jason_S]

[For simplicity], is there a difference between having TWO subs (with sub1 producing channel X's bass and sub2 producing channel Y's bass) and having ONE sub that is producing both channels, X and Y, worth of bass? I have probably already posed a similar question before, but I have lately been pondering this...again. So with money and room acoustics aside (say you could tame room-induced acoustical anomalies with a TacT RCS system), would dedicated subs hold an advantage over just one or two subs? Would ded. subs possibly be able to produce greater SPL levels because all bass signals are not taxing a single/dual subwoofer(s)? I suppose I'm asking this stuff "again" because I haven't been getting enough hardcore fact, just a few hypotheses.
For a 7.1 theatre, there must be a difference between 1) having each of one or two subs producing 8 channels worth of summed bass material--8 or 16 total signals and 2) having each of eight subs producing just one channel of bass--8 total signals.
I do hope everyone realizes, although I'm sure many do, that having eight dedicated subs DOES NOT mean that EACH sub is producing 8 channels worth of summed bass material thus yielding 64 total signals. So it should not necessarily be said that dedicated subs means "having MORE bass," rather it is another way of distributing each channel's bass. (For example if I wanted eight dedicated subs of 15" each in my smallish room, that WOULD NOT be the same as a summed-bass signal split eight ways. Right?) So in some instances where bass levels are not high amongst all channels, 8 dedicated subs may not sound much different than two subs producing a sum signal. But in other instances where there are high SPL's at low frequencies amongst all channels, 8 dedicated subs may wind up producing all of the bass with less strain than just two subs trying to put out all the SPL and low freqs of 8 channels worth of bass. Again, does this sound right?
I better stop, so I'll shut up...for now.
[Edited last by Jason_S on October 27, 2001 at 04:18 PM]

 

[RobertR]

Hey, Frank Manrique actually has EIGHT SVS subs in his room and is planning to have MORE!
------------------
[Edited last by RobertR on October 27, 2001 at 04:50 PM]

 

[Jason_S]

Yeah, I know about that. I think they're all 16-46's too. Awesome and crazy at the same time!

 

[Jason_S]

I don't mean to beat a dead horse here, but I was doing that thinking I often do. I wonder: if I had about eight 15" dedicated subwoofers (NOT a summed signal) in my 12'x8'x14' room, would the tremendous amount of air displacement seriously cause damage to my house, much less my second-floor home theatre room? (This is a serious question, guys.)
Also, how closely related would you guys say air displacement and frequency response/SPL are? As with dedicated subwoofers, you have a certain bass signal at certain sound pressure levels being reproduced by any possible amount of channels at one time, and this is done by 12", 15", or 18" drivers for example. But aside from the frequency response and SPL, does air displacement act somewhat independently and differently based upon driver size? And what is more damaging on its own--low bass @ high volume levels or air displacement? When I mention "damaging," I mean damaging to human hearing as well as to the HT room's structural integrity. Does the buildup of displaced air in a small room (like mine) create any type of harmful phenomena?

 

[AaronNWilson]

Russ Herschlemann disagrees with corner placement of subs. He thinks you should place subs on either side of the centerline of the room, and you should place the extra subs at all of the null points of the room which are calculated via using the axial resonances of the room which are calculated from the room dimensions for rectangular rooms.
After placing my sub in Russ' recommended location I achieved a much more uniform dispersion of bass throughout the room.
Aaron

 

[Mark Zimmer]

On a slightly related question, how do you calibrate multiple subwoofers? One at a time, I would presume? Would you still have them at the same levels, or would you reduce to allow for the fact you now have two going?
------------------
"This movie has warped my fragile little mind."

 

[Clinton McClure]

My HT/living room is 27'w X 16'd X 10'h. Right now I am only running one 10" sub which can pretty much hold it's own. I have budgeted a Servo 15 for next year, and have even entertained the thought of running two Servo 15s, one on each side of my HT and putting my 10" in the rear between the surrounds and running it off the surround channel.
------------------
My DVD Collection Casa del Clint