What I mean is: Has anyone gone from 25-31 to 20-39 or 16-46 or vice versa, and if so, what were your impressions? I went from the 20-39PC to a 25-31PC Plus. At very loud volume, the 25-31PC+ does not seem ruffled in any way, but I think I miss the lower bass more than I enjoy the slight (and I do mean slight) bit more punch, or slam. I think I should have gone the other way(the 16-46PC Plus). But, back surgery intervened right after delivery, and I never got to really demo one against the other before the return period was up. I know it can be tuned down to 20Hz, but I figure that is not as good as getting one already tuned to it by design. I guess I'm just curious as to whether anyone else has experienced ups or downs in the various tunings available. I will also say this: Either one trounces all of the other subs I've heard (I have not heard the big servo models from Paradigm or Velodyne, though). So don't misconstrue this to be an anti-SVS thread, because it is not. I can understand that anyone with a 25-31 would be thrilled after putting it into their system. But I think I was spoiled by the 20-39's lower extension. I should add that my room is only 12x13x8, so the extra output of the 25-31 is probably superfluous, but that's the kind of guy I am.