speakers for classical music

Full orchestra and solo piano are the benchmark source materials for challenging speakers. Most can't hold up under the pressure, they weren't designed for it. If the speaker can stand up to those sources without stressing, without distorting, without sounding stuffy or wooly, and deliver the full dynamics, transients and bandwidth, it'll be a very special speaker. The best ones I've heard for this have always been active. I've heard some passives come close, but to really deliver, actives have a decisive edge. There are other important variables that come into play, but active is a good place to start looking.

Musicnoise:

When I listen to orchestra music and the peaks are exceeding 100 dB, it's VERY loud, and then moderate to low volumes passages sound unnaturally higher in volume than they should. It sounds like you're looking for a speaker that's dynamic, very neutral, low distortion, and open sounding, with no box stuffiness or coloration. One that will illuminate the room with a linear response both on and off-axis.

Seriously look into the Linkwitz Lab Orion if the budget isn't restricted. Check their website for people willing to allow auditions. If you're anywhere near the Ohio-Indiana-Kentucky area I'd be glad to let you audition both the Orion and the ∏ Audio systems in my home. Let me know.

Loudness is certainly subjective. 80 dB is loud, but not LOUD. If I were trying to have a conversation, 75 dB is too loud. For rock 80 dB is mezzo-piano. It's all relative.

I have thought about taking an SPL meter to the symphony many times, never remember to do it. I suspect Mr.T is correct that the level won't exceed 90 in the back row, perhaps peaks will register in the mid 90s mid orchestra and only the front few rows will get anything approaching 100.

I put on the Sheffield Drum & Track CD yesterday. Cranked it until a few peaks were just tipping an amp into clipping. Peaks still didn't exceed 100 dB at listening position and it was good'n loud— almost as loud as a drummer sitting in front of me.