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From: holdenm@thor.acc.stolaf.edu (Mark Holden)
Newsgroups: rec.music.makers,rec.audio,sci.electronics
Subject: Amp upgrading/modifying question
Keywords: Sunn beta-lead solid state yuchh!
Message-ID: <1790@thor.acc.stolaf.edu>
Date: 11 Apr 89 10:04:13 GMT
Followup-To: rec.audio
Organization: Saint Olaf College
Lines: 23


	I've got a Sunn Beta-Lead guitar amplifier that I'd like to upgrade,
hopefully to be quieter, and maybe better sounding.  It's preamp scection is
based around 8 1458/4558 op amps, which to my understanding are pretty generic,
general purpose, and not terribly impressive in either quietness or response.
Now, I believe that the TL082 (RS# 276-1715, $1.98) JFET op amp is a pin
compatable replacement that's both quieter, and has better response.  My
questions are these:
	1) Is this thing really compatable, or am I wrong? (the IC's in general
	are RC4558's and one 1458)
	2) will this make a noticeable difference? 
	3) since the amplifier has a builtin overdrive in the fasion of 
	gain/level per channel into master volume, will using FET op-amps
	change the overdriven sound much, I understand that FET stuff soft
	clips over a range, as opposed to others which hard-clip at a given
	point.  From a guitarist's perspective this would be good (more of a
	tube sound)
Any comments aybody?


-- 
Mark Holden  (holdenm@thor.acc.stolaf.edu)
No user servicable parts.  Refer servicing to qualified service personnel