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previous: Andy HiThanks for your s... -- 1/3/2000 8:33 PM

Re: Modification for Mesa Boogie .50 Caliber

1/3/2000 10:10 PM
marrk	Re: Modification for Mesa Boogie .50 Caliber Right, mine is the .50+. I also have a .22 cal that uses the el84, has a similar preamp structure, yet sounds pretty good esp. when cranked up. My .22 doesn't have the EQ which is very necessary in these amps. Does your amp have the EQ? The .50+ has "auto select" which allows using the eq for overdrive only, if desired. This is how I run mine. Anything I use in my effects loop needs to be trimmed down quite a bit. I use an Alesis Midverb3 with input/output volume controls and it matches up nicely. You have some good tubes there so that can't be the problem. I used a 12AY7 a few times and this did tame that "high gain" sound a lot. The headroom in the clean channel suffered too much though to use all the time though. If your schematic does not show the voltages on the output tubes(it should) call Mesa and ask for them. It is possible that some resistors have gone out of spec. When my amps hit the 10 year old mark, the carbon comps had drifted in a few areas. In fact, one resistor in the .50+ is designed to burn/melt down during use! They have been great to me when I have needed tech help. Good luck, Mark

1/3/2000 10:10 PM

marrk

Re: Modification for Mesa Boogie .50 Caliber

Right, mine is the .50+. I also have a .22 cal that uses the el84, has a similar preamp structure, yet sounds pretty good esp. when cranked up. My .22 doesn't have the EQ which is very necessary in these amps. Does your amp have the EQ? The .50+ has "auto select" which allows using the eq for overdrive only, if desired. This is how I run mine. Anything I use in my effects loop needs to be trimmed down quite a bit. I use an Alesis Midverb3 with input/output volume controls and it matches up nicely. You have some good tubes there so that can't be the problem. I used a 12AY7 a few times and this did tame that "high gain" sound
a lot. The headroom in the clean channel suffered too much though to use all the time though. If your schematic does not show the voltages on the output tubes(it should) call Mesa and ask for them. It is possible that some resistors have gone out of spec. When my amps hit the 10 year old mark, the carbon comps had drifted in a few areas. In fact, one resistor in the .50+ is designed to burn/melt down during use! They have been great to me when I have needed tech help. Good luck, Mark

Replies:

Andy Thanks Mark.i agree, the eq... -- 1/4/2000 8:12 PM