The comments on the string pluck "punch" are very applicable to my situation. I couldn't help but wonder if it was my room acoustics but now a number of facts have conspired to convince me it's not my room. These facts are that others report limited punch in your nicely treated space, the 300W STF-3 that is currently in my room has very good punch (but a terrible finish as I previously reported) and my 150W Sony has punch too. I would take the 600 over the STF-3 and Sony any day but I also want the punch to boot
. I'm therefore convinced it's not my room.
Although the EP400 seems to have the potential to provide that punch with its 150Hz cut-off, it still does not. At least not in my space. I can definitely hear moe punch than the 600 (although I again prefer the 600 over-all) but it's a "teaser" rather than the real thing. When I'm at Jason's later this week, I'll see if the 400 provides any more punch in his much smaller space.
If you situated three 400s in your space, they wouldn't create the "punch" of the Fathom would they? I don't believe the punch is a factor of the number of subs or even the power of the subs. Rather it's a function of the cut-off frequency, the slope thereafter and the transient response of the entire sub-woofer system. I don't know if the Fathom has selectable slopes but if you were hearing that kind of a punch, I'm sure that the slope was 12dB/octave or less.
Again, very informative and thanks for posting.