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previous: Mark John,Thanks for the... -- 4/14/2000 7:09 PM

Re: Princeton Reverb distorts at low volume levels

4/14/2000 11:54 PM
Keith	Re: Princeton Reverb distorts at low volume levels I have the original schematic that came with the amp and it says AA1164 on it and calls for a GZ34. From the research I've done on this so far I think that is correct. I believe I read on Greg Gagliano's page (Fender serial number research) that there were a few of these out there with incorrect tube charts with the model AA764 on them. As the story goes, Fender later discovered the mistake and changed the number on the chart back to AA1164. I don't know how many left the factory that way. I'd be glad to scan and send you a copy of the schematic if you'd like. It calls for a 125P1B, the same number stamped on my PT. I checked the schematic on the Fender Amp Field Guide and it uses the same PT but calls for a 5U4GB! Aspen Pittman's book has the same schematic with the 5U4GB. Now I'm really confused. So we're back to the question... can I put the 5U4GB in my Princeton? I'm just dying to try this if you haven't noticed. I'm going to compare the 2 schematics to see if there are any other differences. I took a quick look at the 2 schematics and the component values and voltages appear to be identical except for the rectifier. Hmmm.

4/14/2000 11:54 PM

Keith

Re: Princeton Reverb distorts at low volume levels

I have the original schematic that came with the amp and it says AA1164 on it and calls for a GZ34. From the research I've done on this so far I think that is correct. I believe I read on Greg Gagliano's page (Fender serial number research) that there were a few of these out there with incorrect tube charts with the model AA764 on them. As the story goes, Fender later discovered the mistake and changed the number on the chart back to AA1164. I don't know how many left the factory that way.

I'd be glad to scan and send you a copy of the schematic if you'd like.

It calls for a 125P1B, the same number stamped on my PT. I checked the schematic on the Fender Amp Field Guide and it uses the same PT but calls for a 5U4GB! Aspen Pittman's book has the same schematic with the 5U4GB. Now I'm really confused.

So we're back to the question... can I put the 5U4GB in my Princeton? I'm just dying to try this if you haven't noticed.

I'm going to compare the 2 schematics to see if there are any other differences.

I took a quick look at the 2 schematics and the component values and voltages appear to be identical except for the rectifier. Hmmm.

Replies:

jason The 5U4 pulls 3 amps of heater curr... -- 4/15/2000 12:23 AM
John Stokes Well, Keith, here's the deal. If y... -- 4/15/2000 12:33 AM