It sits between the amplifier (either at line level if you have that or with an attenuation cable at speaker level). It does not do low pass filtering or anything for you. You have to figure that out in the usual way. All it does is measure the room response of the subwoofer (an easy one time only automatic procedure with the provided microphone) and then applies an appropriate correction curve to the signal before it reaches the subwoofer. Since it removes bass peaks you may have to increase the sub’s level a bit, and that is all. See here for the manual:
http://www.dspeaker.com/fileadmin/datasheets/dspeaker/antimode8033CinemaSIIen.pdfI have found it very easy to use, and remarkably effective for relatively little money. See here for a review:
http://www.theabsolutesound.com/articles/dspeaker-anti-mode-8033-dsp-subwoofer-equalizer-tas-204/In my case, my main speakers are Quad 2805s, and they lacked a bit of deep bass. So I added a B&W PV1d, but found it hard to integrate the sub perfectly. So I remembered all those stories about fasts stats and slow subs, and feared I had made a mistake. Then I stumbled upon the Antimode by chance and decided to take a gamble, because the theory and the physics seemed right, and so did the room response measurements that they presented as examples. And indeed, the bass suddenly became much tighter, more tuneful, and ’faster’. What I learned is that fast and slow has nothing to do with the moving mass of the speaker but with the slowly lingering decay of the in room response that you can see in waterfall plots. Stats are fast because they are dipoles that excite fewer room modes, and subs are slow because they go low and thus excite many room modes. Deal with those, and the sub becomes almost as ’fast’ as the stats.
I have since learned that multiple subs are another good way to proceed, and the conclusion is, of course, that combining those two approaches is likely to give the best results.
