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previous: marrk GFR, What effect will this have to... -- 1/5/2000 1:10 AM

Re: Modification for Mesa Boogie .50 Caliber

1/5/2000 10:24 AM
GFR	Re: Modification for Mesa Boogie .50 Caliber With a 12AT7 you'll have slightly less gain at the boost stage, so you'll have less distortion afterwards (but still lots available) with less buzzing harmonics. There are rumours that Allan Holdsworth Calliber's were moded this way. Another mod worth trying is to remove the bypass capacitor at the cathode of the boost stage. This will give you much less gain - the amp will sound more "vintage" and less "shred" If there's still too much gain you can try both mods at the same time (12AT7 with the cathode resistor unbypassed). The graphic EQ on the fx loop (if the amp has not a built-in graphic EQ) can help you to trim off the offending buzz without sacrificing gain and sustain too much.

1/5/2000 10:24 AM

GFR

Re: Modification for Mesa Boogie .50 Caliber

With a 12AT7 you'll have slightly less gain at the boost stage, so you'll have less distortion afterwards (but still lots available) with less buzzing harmonics. There are rumours that Allan Holdsworth Calliber's were moded this way.

Another mod worth trying is to remove the bypass capacitor at the cathode of the boost stage. This will give you much less gain - the amp will sound more "vintage" and less "shred"

If there's still too much gain you can try both mods at the same time (12AT7 with the cathode resistor unbypassed).

The graphic EQ on the fx loop (if the amp has not a built-in graphic EQ) can help you to trim off the offending buzz without sacrificing gain and sustain too much.

Replies:

Andy I'm curious about the mod at the ca... -- 1/5/2000 8:47 PM