This question comes from Gregory:

Q I often read about reviewers or pros using 4-5 subwoofers in their home theater. I have the Pioneer Elite SC-25 with one subwoofer pre-out with two subwoofers connected with one splitter. Do I use splitters on the splitters to connect more subwoofers?

I’m just curious what four subwoofers would sound in my Home Theater especially since I love really good bass. I have two Paradigm Signature Subs connected, but I do have other subs waiting for something to do. Thanks.

In theory four subs is a viable solution to even out small room acoustic peak and nulls, but placement is critical when calibrating a room mechanically with multiple subs.

Harman International’s Dr. Floyd Toole has researched small room acoustics extensively and he has found that multiple subs do even out bass response. Adding subs however may not add the volume increase you seek or deeper frequency extension.

Even bass response is much more critical than volume to achieve a quality listening experience. you may want to look into Paradigm’s Perfect Bass Kit (PBK) and some of its other subwoofer solutions since you are a Paradigm product owner.

Before you invest major money into any product you should check out Dr. Toole’s book:

“Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms”

In the coming months EH will be working with BG Radia’s Igor Levitsky, who is a top engineer and well respected in the audio community on a story that will delve into the topic of low frequency reproduction in the home.

I recently purchased a second identical sub to improve my theater’s bass response.  Here’s what I discovered: 

1)  The version of Audessy I have in my AVR does not recognize multiple subwoofers, so I was going to have to set levels by hand.  Setting levels wasn’t too hard, but trying to find the tradeoff between where the subs sounded best, and where they would be out of the way caused some ‘spiritied discussion’ with my wife. 

2)  Rob nailed it when he said that even response was more critical than volume.  2 subs improved the size of the sweet spot, and moved where the voids were in the room.  I still wasn’t happy with how the bass sounded, as it was only louder, not more accurate.  I would imagine that with 4 subs I could really minimize any perception of uneven bass response, but is that the best bang for my buck?

3)  I will probably need to address the acoustics of the room if I want to keep improving things.  More subs might be a less expensive option than room treatements and a professional analysis of the theater room, but in the long term, I think I would have been better off getting my room analysed and a plan for treatments over buying more subwoofers.

@Paul

” I will probably need to address the acoustics of the room if I want to keep improving things.  “

You are right on the money.  Your “accuracy” issues are probably best addressed in this way.  If you have quality subs in play, which it sounds like you do, adding more will not improve your accuracy. 

Issues with low frequencies usually come from reflections and standing waves.  These things can usually be fixed with bass traps and acoustic panels.

So I decided to experiment, and convinced my best friend to bring over his two subs to add to my two…  The results were impressive, in a knock pictures off the walls sort of way, but I wasn’t impressed enough to consider this option.  My friend though it was awesome however, so maybe I’m being really nitpicky here.

Has anyone given the thought to adding Bass Shakers (Aura) to the furniture rather than large subwoofers throughout the room?  This is kind of “out of the box” thinking, but I believe it might be worth considering.  The effects they create are outstanding in the feel of the bass frequencies. 

For those who have never heard of Bass Shakers, they are essentially counter-wights built into their own containers that you mount to solid surfaces either inside the framework of the furniture or the walls themselves.  They use considerably less power than a typical subwoofer.

I just thought I’d throw the idea out there…food for thought…