Path: utzoo!attcan!uunet!samsung!zaphod.mps.ohio-state.edu!uwm.edu!psyche.mit.edu!jacob
From: jacob@psyche.mit.edu (Jacob Feldman)
Newsgroups: rec.audio.high-end
Subject: Passive Preamp
Message-ID: <9003170016.AA25031@psyche.mit.edu>
Date: 19 Mar 90 14:20:05 GMT
Sender: news@uwm.edu
Lines: 17
Approved: tjk@csd4.csd.uwm.edu

I am also very curious about the by-passing of the gain stage on high
level sources. I have a PS Audio 4.6 which has the bypass option (only
the volume control is in the circuit). Common sense (echoed by many 
salesmen as well as the PS Audio literature)  seems to suggest that avoiding
the gain stage can only be a good thing, as you avoid any colorations
that it might introduce. However, my experience has been to the contrary:
both the PS Audio bypass and an Adcom passive "preamp" I once heard have
a flat, lifeless quality as well as a very peculiar, unnatural-sounding
nasal timbre. This quality was distinctive enough and peculiar enough
to suggest that it wasn't just a question of hearing the faults of the
amp coming through-- at the very least, it wasn't just lack of some kind
of euphonic coloration. I have no doubt that this phenomenon has some
electronic origin that I just don't know but would be delighted if
someone took a shot at explaining.


-Jacob Feldman