-> BG> clean audio sources, but hopefully, you can see the drastic difference
-> BG> in treatment of some musical instruments and typical hi-fi and 
recording
-> BG> sources.
-> oh, I understand the difference, but does that mean that a guitar amp 
eeds
-> to be at full volume (or a little more) to get the desired sound?
-> when I tell people in a band to turn their amps down and let me take care 
of
-> the volume am I doing them a disservice?
Depends; if you are a fan of Spinal Tap, then "11" is the only way to go! :-)
In reality, no, tell them to turn it down. Having been on both sides of the
fence it is a common problem, often due to -either- noise exposure during a 
gig
(ever notice it gets worse as the set(s) progress?) or due to the same reason
effecting their perception of -their- monitor mix (or lack of).
More often than not it's a ongoing battle!
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