[fluke242]

Just looking for thoughts and opinions for my next project.

Low-end.  I really like the idea of 4qty subwoofers to balance out room nodes (Like Swarm 2.0 from Duke LeJeune).  I would also imagine that having more would allow them each to do less, and avoid distortion.

Can I get away with inexpensive subwoofers if I do 4qty?  Or better to spend that on a single high-end subwoofer? 

I am also concerned with the complexity of 4 subwoofers and not even sure how I would manage that yet.  Ideally I want all 4 to auto EQ... I worry about manually EQing each sub, only to have new EQ needs when all four are running.

Any quad subwoofer users in the audience?

Thanks!

[chadh]

I'm en-SWARMed.  But I'm not sure that I can be much help to you.  This is my first exploit with subwooferage of any kind, so I can't compare to a high quality single sub.

What I will say is that I don't seem to have any of the problems that others often complain about with subs.  I don't have any glaring problems with "blending" of the sound from my mains and the subs.  I certainly don't get any directional information from the subs.  I've never measured my in-room frequency response, so I don't know how flat things are - but I think it all sounds pretty sweet.  In general, I really don't know that the subs are working until I switch them off - and then the difference is remarkable.

I'm using an active crossover with a fixed crossover point of 100Hz and 24dB/octave slopes.  And no EQing is happening either (other than via a volume pot that controls all the output to the subs).

For what it's worth, the swarm and active crossover are about the last portion of my system I'd contemplate losing.

Chad

[Bob in St. Louis]

Cheap sub = "One note".    Been there, done that.
It's great to impress your (non-audio) friends with. Other than that, it's a waste of time and money. Mine went into the burn pile not long after I built it. Literally, set it on fire after I cut it up in small enough pieces to carry outside.

Good sub = "musical". Great for music, movies, etc.... 

Check into Open Baffle, and Infinite Baffle configurations.   

Bob

[OzarkTom]

Infinity sold a bunch of refurb subs this summer on Ebay. I picked two up of the Cascade model 12's for $170 each. 300 watts per sub, they sound very mice.

I had a friend that actually installed four 15" woofers in his wall. Mow that was quite some bass.

[turkey]

I'm not sure that you really need 4 subs. 3 inexpensive subs works just fine for me. I use a setup based on info Earl Geddes has published.

I get better bass than I've heard almost anywhere else, including that from some very expensive speaker systems. I've got 3 different subs, 2 10" and a 12", and the most expensive one was $140.

[fluke242]

Thank you for the replies thus far.  It sounds like quantity may work.  Below are my two current plans for low-end, both costing the same ~$2,000

1. Quality - Single monster  Salk Sound Sub (single 15" driver with passive radiators) to match my HT2s
2. Quantity - 4qty Epik Legends (dual 12")

I am just not sure how to manage 4 subwoofers, which DSP if any, etc.  Anyone running 4 subwoofers?   

[turkey]

I am just not sure how to manage 4 subwoofers, which DSP if any, etc.  Anyone running 4 subwoofers?

I didn't use any DSP. I'm running my mains full range, and then I set the x-over frequency on each of the 3 subs differently (roughly 80, 100, and 120Hz) at random. I have one of the subs driven by my extra pre-amp out and the other two coming off of my main speakers (one on the R ch and one on the L).

One sub is in a corner behind my main speakers, one is on a side wall, and one on top of a sturdy table on the back wall. Two of the cones face the walls and I put some foam in between to absorb higher frequencies. The other fires into the carpet.

I turned up the sub in the corner until things started sounding a bit "fuller and weightier," then turned up the one on the side wall. I didn't have to turn it up as much. I added a bit more to the corner, then to the side wall until it sounded good. Then I went to the one on the back wall and turned it up just a bit. I used some Telarc classical recordings, plus the one by The California Project and just adjusted things until they sounded realistic.

Based on what I have heard, I would not recommend a single sub. One sub is only good if you're after sound effects.

There really isn't a whole heck of a lot going on below about 40 Hz in most recordings, so I don't know that there's a need for really deep bass. Maybe if you're into organ music or like listening to recordings of trains.

I suppose some movies might have content below 40 Hz, but I doubt it since reproducing that kind of thing is difficult in the theater (or at home for that matter), so they just wouldn't bother or else maybe they'd toss in some trash at 30 Hz just to move some air. That doesn't even consider the fact that 20-30 Hz in a movie theater at levels high enough to match the rest of the program content is going to rattle all kinds of things and annoy people in the lobby and at neighboring businesses, plus you'd only be able to show one movie at a time because they just don't build those multiplex theaters to contain such low frequencies within a given room.

[roscoeiii]

I am unclear why you vault from 1 to 4 subs. Why not a dual sub set-up?

As for 1 sub vs. dual subs, I was convinced to go dual after reading Jim Smith's "Get Better Sound."  An incredibly good resource for room set-up and questions like these.

[doorman]

Much depends on the type of music/experience you favor.
The "drywall cracking crowd" are often (not always of course) more focused on  things other that an integrated musical approach. If gut wrenching, over balanced bass turns you on, there's plenty of ways to achieve that.
Listen to as many implementations as possible. There are no absolutes.
-decide on which set of compromises you can live with!
Happy hunting
Don

[JRace]

I am unclear why you vault from 1 to 4 subs. Why not a dual sub set-up?

As for 1 sub vs. dual subs, I was convinced to go dual after reading Jim Smith's "Get Better Sound."  An incredibly good resource for room set-up and questions like these.

Using more than 2 subs is done to reduce room related low-freq issues, in essence flattening out the freq response throughout the room.

And there is plenty of content below 40Hz in movies!

I was fortunate enough to have at my disposal for a short period 3 subwwofers:
1) MartinLogan Descent i
- 3 10" drivers / 2 band narrow eq / sealed

2) Velodyne IC-600
- 1 12" driver / autoeq / ported

3) Thiel SS2 Smartsub
- 2 10" drivers / boundary compensation circuitry / sealed

I have the ML sub up front beside the main speakers (ML Vista).
The Velodyne is mounted in the ceiling, in the front 1/3rd of the room, to the side.
The Theil was located behind the couch. (it has since been returned as it was just a review sample)

To setup I first set each sub (on its own) to match the mains at 75dB using a SPL meter.
Then I ran the auto-eq on the Velodyne, set the Thiels boundary compensation to the respective distances from the rear and side walls, and I left the ML eq at flat.

On there own each sub was capable, with the Thiel being the best on its own. With all 3 running, it was astonishingly flat throughout the room, and the areas that were very boomy before (adjacent kitchen and dining rooms) were no longer a problem.

[fluke242]

I am unclear why you vault from 1 to 4 subs. Why not a dual sub set-up?

As for 1 sub vs. dual subs, I was convinced to go dual after reading Jim Smith's "Get Better Sound."  An incredibly good resource for room set-up and questions like these.

Comparing extremes to help make a decision.  It will all cost the same, but I am leaning towards 4 subs to help balance out room nodes.  I like the idea of more drivers doing less and questioning if it will compensate for quality. 

I shy away from dual subs because they don't solve room node problems like a proper 3-4 sub configuration.  3 sub config is a tad more complicated than 4 sub, as one subwoofer is usually elevated. 

I am not seeking gut wrenching bass and plan to balance the subs flat.  I am 100% music in this room and am looking for realistic low-end.

[fluke242]

Thanks again for the posts!  I feel comfortable moving forward with 4qty subwoofers and will follow Duke LeJeune's placement to start.  This project is a few months out, as I am just finishing up my last - replacing my pre-amp and DAC.   

[turkey]

I shy away from dual subs because they don't solve room node problems like a proper 3-4 sub configuration.  3 sub config is a tad more complicated than 4 sub, as one subwoofer is usually elevated. 

It's recommended that one be elevated, but that's not to say it wouldn't work if it's not.

Maybe you could try 3 and then get another one if 3 isn't working out?

[fluke242]

It's recommended that one be elevated, but that's not to say it wouldn't work if it's not.

Maybe you could try 3 and then get another one if 3 isn't working out?

Haahah, I read that too fast.  "Try 3, if that doesn't work add 3 more" 

Good point, maybe 3 is enough - but from reading 4 seems best and I am open to trying it.

[cujobob]

http://mehlau.net/audio/multisub_geddes/

Multiple cheap subs for best sound quality, but if you want to go extremely low, you have to be careful with which subs you choose.

[Duke]

One thing to keep in mind with a scattered multisub configuration is that the subs will add in semi-random phase at the upper end of the bass region, transitioning to in-phase below the lowest room modal frequency.  The net effect is a boosting of the bottom end by about 2 or 3 dB relative to the top end of the bass region, and this is in addition to gain from room boundary effects.  So if you're going to build four identical subs, I recommend that you NOT design them to be "flat".  Rather, shoot for a gentle roll-off across the bass region.