07-10-09: Skyline889That should be a good amp/speaker match. That Denon is a big, heavy class A integrated with huge current reserves and the B&w has a pretty friendly impedance curve and its sensitivity is around 89 dB.
I'm running them off of my Denon PMA-2000IVR integrated. It's a warmer high current SS amp so I was surprised at how little mid-low bass there was.
Also, the DM603 S2 was discontinued years ago, Stereophile reviewed the S3 in 2005, and the reviews of the S2 on Audioreview go back ten years. So it's definitely not a break-in problem.
So I suspect it's a room placement, spiking, or cabling problem, or a bit of all three. First thing to do is check to see if your speaker cables are wired out of phase to the speakers. That would easily account for why a floorstander known for dipping into the 30's has less bass than some Klipsch bookshelves.
Second, perhaps the cable itself is a mismatch and you need a very low gauge feed to the woofer terminals.
Third, maybe one or both of the woofers are blown. This is a 2-1/2 way system, which means it's a 2-way that gets augmented by the second woofer from about 450 Hz on down. If the woofers are blown, the mid/woofers still work but would have much weaker bass than when the lower woofers are helping out. This could also account for the bad tonal balance you're hearing.
Fourth, make sure the speakers are making contact through all the spikes or cones to the floor below. If you have hardwood floors, use cones (or spikes) plus floorsavers.
If all those things are OK, then you need to experiment with in-room placement. There may be some cancellations going on with the speakers in their current positions. How does their position compare with what you had for the Klipsch's?