Subs and the quest for bass.

I recently picked up a Rythmik Audio F12SE subwoofer to compliment my B&W 805S. Happy with it, and the Rythmik has very musical bass. I am using an active crossover (NHT-X2 crossing at 80hz) and a Velodyne SMS-1 sub equalizer to even out the low end response. (I have a lot of bass modes.) The SMS-1 is very useful, and with help of quite a bit of EQ, my low end response is almost perfectly flat.

While it sounds great, I keep wondering how different the sound would be if I didn't have to use so much EQ. Then I started thinking maybe I should add another sub? When I started I told myself I would not do it. Also I had so much trouble getting good placement and setup with the first sub, I don't know if I even want to further complicate things.
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I was happy with using one sub before,and didn't realize what a second sub could do for the music.
Musically,a second sub gave the music what I'd call more of
complete foundation.
I didn't realize how much of a improvement a second sub would
bring to the music.
If your sceptical,I'd see if you could borrow one and let your
ears decide.I think you'll be quite surprized and I bet you'll
wonder why you didn't do it earlier.
For me I won't go back to one sub,that's how much an improvement two will give you.
If two can improve the music in my not so ideal room,
I'm sure you'll like what two can do for you.

As you probably know, I use exactly the same set-up, but with 2 Rythmiks. If you go this way, you will definitely reduce the amount of EQ you deploy but:

1) I didn't hear much/any difference between a single sub and dual subs with the SMS. The amp in a single sub never sounded remotely taxed by the EQ'd signal, so I was never aware of the EQ being applied. Partly, of course, this is the result of the EQ needed for my room which may differ dramatically from yours. If so, all bets could be off.

A single sub just sounds neutral, powerful, and perfectly integrated in my set up. One sub was enough, but I started with two and decided to stay that way. Doesn't hurt, but - honestly - it might well be overkill.

2) The SMS is still a great tool for dual subs. Even though the "native" response of dual subs is much, much smoother, I still use 3 bands of EQ to address meaningful deviations in response. However, it's the "fine tuning" with the SMS right at the x-over point that really makes a difference. One sub, two or even four, the SMS (or equivalent) is still the best customizable subwoofer high cut that I've found.

The good news is the the Rythmiks are money back - so you can try a second one on their dime. Just don't expect a lot of impact.


PS Make sure that you experiment with the Q setting on the Rythmik - it does make an audible difference.
I see that I dropped one sentence re: my specific set-up.
I always sit in 1 spot - no variation. If you move around in your listening room, the second sub will definitely provide benfits vis a vis an EQ'd single sub.