I'm not sure why everyone is ragging on the B&W 702-S2. I've auditioned these speaker several times and am absolutely not hearing what other people are claiming. They do have a crisp detailed Mid/High but at the same time maintain a smoothness and lack of harshness that can be found in some speakers. To my ear, which are admittedly old, these speakers came off very clear and well balanced. I've definitely heard better but for considerably more money.
As others are suggesting, the problem is either the wiring or the room. For every system the first thing I recommend is that you ABSOLUTELY BEYOND ANY SHADOW OF A DOUBT make sure the speakers are wired correctly. That in every case the Amp(RED+) goes to the Speaker(RED+). Nothing will suck the life out of a speaker like one of them being wired backwards.
Next where are the speakers in the room? If they are on the 24ft wall playing into the 13ft space, that could explain a lot. If they are on the 13ft wall playing into the 24ft space that is certainly better.
The next aspect that must be asked is, where are the speakers place relative to nearby walls. Placement is always a big issue. If the speaker are against the back or side wall then that explains a lot. If you put your speaker near a boundary surface, that boosts the bass, but what you hear is the Mid/High becoming more recessed and muddy. Placement issues are easy to determine. As a test, simply pull the speakers forward about 3 to 4 feet into the room and at least 3ft away from the side wall. If the speakers now sound better, then you have a Placement problem. Once that is determined, start working the speaker back until you find a workable compromise.
Most people, for some odd reason, push their speaks way too far back against the wall. For myself, I simply move the speaker forward even with the front of my equipment stand which is itself about 8" forward of the wall behind. That gives me in the range of 14" behind the speaker, which, while not perfect, works for me.
Also, you might try plugging the Port if the speakers must be relatively closely placed. That will soften the bass profile of the speakers, and as the bass is softened, the Mid/High becomes more clear.
Classe are good amps from what I can determine. The Rotel Pre-Amp should be fine. And in my opinion, the B&W 702-S2 are fine speakers, though we each have our own taste. That means that something else is probably the problem.
- Speaker Wiring - Even the best of us get this wrong on occasion. Absolutely verify it.
- Speaker Placement - the most often made mistake. As indicated, a simple test can verify if this is the problem.
- Plug the Ports - this can soften the bass, and clear up Mid/High
- Room Acoustics - Highly reflective walls can definitely blur the sound.
Also if you can explain how the speakers are not sounding right? Too much bass, not enough bass? Blurred muddy Mid/High? Other? Understanding how the speakers don't sound right would help us understand why the speakers don't sound right.
Just a few thoughts.
Steve/bluewizard