Two X-ref 10 subs make any sense?

[anthonywoy]

As the title says, do 2 X-ref subs make any sense? I know they are not the most powerful sub, but how much more extension would I be getting? My room is small, sealed, about 1700 in space. The sub goes down to the low 30Hz range,(corner loaded, so my guess I can get into the mid to high 20Hz) and then the limiter kicks in before it starts to distort. How much would you think it would add to the low end, or am I limited by the sub?
(Using an Yamaha RX-A800 receiver)

Also, the Audioholics review of the sub by Gene says:

To help offset the aggressive HPF of the X-Ref 10, I played around a bit with the two EQ bands. EQ1 was set to 25Hz, +2dB, Q = 1.5 while EQ2 was set to 28Hz, +2dB, Q=2.5. I then offset the EQ level to -0.5dB to level match the curves and get a better understanding of the effects the EQ had on frequency response. As you can see the EQ curve (blue) lowered the 3dB point from 32Hz to 29Hz and we achieved a +4dB output advantage at 30Hz as a result. I didn’t want to over EQ or EQ down too low in frequency but instead focused on where the output gain would be most meaningful for this product.

I went back and re-ran my listening tests and found the XRef-10 was now closing the gap with the Ultra 12 in terms of low end output. Musically, I felt the X-Ref 10 outdid the Ultra 12 even more so, now that it had a little extra low end kick.

I followed what Gene says, but should I be using the EQ to get rid of any humps in bass for my room? Or would you agree with what he said to do?
I have set things up with YPOA.

Can anyone point me to a good beginner guide for integrating the sub into the rest of the speaker system.

[shadyJ]

If you already have one, adding another isn't going to give you much in the way of extension. Another one can flatten out frequency response a bit and give the EQ less to do, which is always a good thing. Adding another can also greatly reduce localization, so the sub doesn't draw attention to itself. I think its a worthwhile upgrade, but don't expect a big increase in output or any deeper extension.

[anthonywoy]

Thanks shdayJ, I figured as much. Could improve the bass response in the room, but not get much more extension.

[timoteo]

Putting both subs in the same corner will give you an additional 6dB. But you won't get any more extension or any better frequency response.

Having the subs PROPERLY located in two DIFFERENT locations can give you better frequency response (flatter) & also give you an additional 3dB compared to a single sub. But again you will not get any more extension.

[KEW]

But again you will not get any more extension.

However, you are more likely to appreciate the extension you do have.

[timoteo]

Dual subs is always a good idea!

Yes the extension can be more noticeable which may give you the impression that it is going lower.

Good point KEW...