For the sake of completeness.....the Rythmik PEQ plate amps (all those not including XLR connections) allow the sub to be fed from either a pre-amp (line level) OR a power amp (speaker level). RCA jacks are provided for line level hook up, binding posts for a high level signal from a power amp. It works the same in that regard as both Vandersteens and REL’s. You can try the sub both ways, and decide for yourself which you prefer. The Rythmiks also have an excellent set of controls, with adjustable phase (not just a 0/180 switch), damping, x/o frequency and slope, and one band of PEQ (parametric equalization, for room modes). None better on the market.
I myself don’t know why anyone would want to add the imperfections of a power amp (they all have them) to those of a pre, but it’s worth a try. The notion that taking the sub signal from the power amp that is feeding the speakers will be of benefit in the effort to make the sub sound "as one" with the speaker strikes me as specious (except perhaps in the case of the Atma-Sphere OTL’s---no output transformers, with their well-known problems doing bass), but I’ve been mistaken before. Heck, I got married once.
For anyone living in or around NYC wanting to hear Rythmik subs, Sterling Sound Mastering has three pair of Rythmik F15’s (15" woofers instead of the F12’s 12") in their rooms. Don’t tell them I sent you. ;-)
