Actually, I believe it's pretty much a guarantee that Nick has a problem with vibration contamination. Since everybody else does too. Vibration problems are kinda' like dirty AC and dirty underwear. Everybody's got 'em. :)
A system where vibration contamination has not been addressed or improperly addressed typically leaves a mushy and dulled residue that renders a performance somewhat lifeless where it becomes difficult to make the distinction between a strike at the high-hat cymbals or a rim shot. This effect is generally the opposite of what one would consider bright.
As far as I know, the only way perceived brightness will occur is when the vibrations have been properly addressed using the coupling methodology as opposed to the decoupling methodology.
Though the coupling vibration control methodology provides essentially the same sonic benefits across the frequency spectrum, there can be a perceived increase in 'brightness' due to the fact that most systems are at least somewhat bass deficient.
Therefore, since the presentation is already improperly weighted toward the highss, any further enhancements would simply give the illusion that the scales have been tipped even further toward the higher frequencies.
Properly addressing the bottom end thru proper amplification, speakers, and/or cabling would be the far better way to address this so-called 'brightness' if it were in fact deemed to be the result of vibrations.
-IMO (Disclaimer: For I too am a rack manufacturer.)
