Comparison of various subwoofers for 2 channel audio


I have a 2 channel audio system, and I appreciate how subwoofers have augmented the sound quality of my system (with electrostatic speakers).  I currently am using a pair of Martin Logan Balanced Force 212 subwoofers, but I’m thinking about adding more subwoofers for a total of four in order to help balance the low frequency sound waves.  I’m considering adding a pair of Rythmik, SVS, or perhaps Velodyne subwoofers to the system.  Does anyone have experience with many of those brands, and how well they integrate with electrostatic speakers in a 2 channel system, or perhaps should I just get a second pair custom built with certain specifications?  
Thanks.

drbond

@decathlon1991 

That sounds like a rather unique solution:  3 high on each side!  One of many possible solutions, as the next post by @mrdecibel went from 2 subs to 1.  

It's great to hear the variety of approaches hear to 2 channel music.  I think I'm going to go with 4 dual opposed subwoofers, with the first 2 placed in a slightly staggered fashion just to the inside of the left and right speakers. 

 

I think I’m going to go with 4 dual opposed subwoofers, with the first 2 placed in a slightly staggered fashion just to the inside of the left and right speakers.

The easiest/most effective first shot may be to just place them in all four corners if possible as this is probably less likely to produce peaks/nulls. Better yet, put them at the midpoint against each of the four walls as that is supposedly optimal placement — that’s what I’ve heard from an expert anyway, and it’s free to try of course. FWIW.

I had a pair of SVS Micro 3000's which sounded excellent with the Dynaudio and  Graham Audio speakers I was using at the time. Now I have a single KEF KC92 sub paired with the Q Acoustics Concept 300 monitors, and I couldn't be happier. Great bass extension, definition, and the elusive texture people sometimes talk about when describing bass. I really didn't appreciate that until I experienced it first hand with the KEF. It allows one to hear the differences in bass instruments more clearly.

@vdotman 

What are your impressions about the KEF vs SVS dual opposed subwoofers?  (I realize that you also changed speakers, so a direct comparison may be difficult.)

Thanks.

@drbond Your speakers are 7 feet tall. How high is the ceiling? If it is over 7' 2" tall the behavior of your speakers drop to point source at about 130 Hz. If you are crossing below 130 Hz it is probably more accurate to stick with the two subs you have, cross at 100 Hz and turn up the volume on the subs. They should be about + 10 dB. What are you using for a crossover? 

I have succeeded in bi amping the Sound Labs. Roger helped with the conversion. There are no passive crossover parts in the system. It was not easy going, but the end result is pretty amazing.