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Hoffman Amps Forum image Author Topic: Schematic questions  (Read 1806 times)

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Offline idontknowyou

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Schematic questions
« on: May 25, 2024, 06:01:25 pm »
I have an amp project that needs a full preamp rebuild and I have 3 octal sockets available. My idea is to have a single channel from an ampeg B15 but try to add reverb and tremolo. I found old forum posts detailing a single 6Sl7 reverb circuit, and a single triode tremolo using a vactrol. I have drawn up and attached a preliminary schematic.

I copied the preamp of the 1964 B15S except I moved the volume control to immediately before the 2nd gain stage. This is where I tied in the tremolo. After the 2nd gain stage I copied fender ab763 design to split the signal and mix it back in before a 3rd gain stage, which I used the component values of the 1st gain stage for. I feel confident and prepared to play around with component values but I had a couple initial questions:

1- does having the volume along with the tone stack, before the 2nd gain stage make sense or should I move it back to where it was?

2- if I do keep the volume with the tone stack, will feeding the tremolo to that point load down the stage too much? Is there a better place to insert the tremolo?

3- anything on here look like a bad idea?

Thanks for any thoughts!

Offline sluckey

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Re: Schematic questions
« Reply #1 on: May 25, 2024, 06:31:08 pm »
Looks doable. Be prepared to experiment.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

 


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