Orchestral brass and fanfare - analysis of system

I generally agree with the comments above, but let's take the answer a step further. If the problem proves NOT to be the recording, then I'd say the speaker is the culprit. I doubt very much that either the preamp or the power amp is the cause of the problem.

Bear in mind that massed brass generates a lot of acoustic energy in the upper mid-range, not just the high frequencies. So, you have be experiencing a limitation caused by the B&W 805's. I have sold B&W speakers professionally, and their lower-priced models can be a little edgy in the frequency range you are describing. Try borrowing a set of speakers that are known to have smooth upper-mid and high frequencies and see how the system sounds.

The last item you may want to explore are your interconnects. You don't state which model of AQ interconnects you are using, but if they are among the lower priced models that AQ makes, you might want to try a different brand, such as Kimber's Hero, or Alhpa-Core Goertz TQ2. I have found these two interconnects to do a very nice job in my own system with the upper frequencies.

Not only, Patrick!
The symphonical brass recordings do stress a lot the speaker drivers with the widest freequency spectrum including unaudiable freequencies(that basically signify the tembre of a particular instrument or group) that are present in this case on significant levels that are probably beyond the speaker curve. To reproduce symphonical brass I believe there should be the power-hungry full-range speakers and a huge power to drive them. If these conditions are not met there will be a huge amout of destructive mutual influence between different instruments and the ONLY ONLY way to cut this problem to the roots is to go to the concert hall and listen to it live.
Thus, the only test for the speaker/amp I don't do is the symphonical brass mentioned here even despite my adoring of Symphony 5 and 9 of Beethoven. Not for my budget or even not for my twice-budget either.
In case with CD or even HDCD(forbid my analogue habbit skeptics) the highs are extreamly limited and cut and so might and probably do inflict such distortions that are unaudiable on higher volume levels but still I bet present.
I must say that the author of this forum should contact Sean(the member of the 'gon) that has a pretty vast knowlege how it's done in reality and how expencive it could be. Also talk to Rives that might define if there is some room issues in that case.

As those above indicate, it could be a number of things. There's a lot of symphonic music that is quite dynamic even awesome.

If you are listening to decent recording labels such as Telarc, Reference Recordings, etc., then I would absatively posilutely disagree with those above who say it's probably the recordings.

By all means start by looking at your most inexpensive components first.

But in my experience and readings, I believe the culprit most likely is in the amplifier and it's designer. There are those who believe that all amps simply amplify the signal with a certain current and power rating being the only difference.

In my experience and reading, this is the furthest from the truth and can be the most corruptedly designed component in a given system. Some to many amps introduce potentially serious flaws at reproducing higher and/or lower frequencies, where higher volumes and/or complex music can lead to compression and/or congestion. Not to mention amps that roll off the highs or soften them or roll off the bottom end, etc.. Most of these ill-affects are coming from a design flaw or weakness within the amp.

I'm not a Krell fan anyway, so if it were me, I'd look first at the amp. But that would also be perhaps the most expensive remedy.

-IMO

I forgot to mention that I also have a REL stadium III sub-woofer in the system. This is an important omission since it makes a REAL BIG difference in my system's overall sound on orchestral and brass music. Sub-woofer frequencies are an intrinsic part of the spectral presentation of trumpets (e.g.), as surprising as this was for me to realize.

Judit,
Subwoofer is not enough. There probably has to be super-tweeter as well.