If any of you use high end sample libraries - Vitous, etc., do you
normally use them as is out of the box or do you find you need to
massage them a bit with EQ etc. to get the results you want?

I have the Master Bits Sound Clips sample library and have been making
Soundfonts, playing them through an Audigy 2. They're stereo, 44.1.

What I run into is that the samples sound great by themselves, but
when combined - such as symphonic strings or orchestral unison samples
- something seems to get lost in the translation. It's hard to
describe, they don't sound bad, but they seem to lose some of that
ultra realistic sheen that they have when played by themselves.

Any suggestions?