Hi guys,
Although the amp is half tube, the preamp in question is solid state, so I'm posting here. 🙂
I'm trying to figure out how to safely add a "kill EQ" switch to the clean channel of this amp. In fact, I would like to use the "Normal/Bright" switch for this purpose, which is already there, because I never user use the "Bright" mode anyway.
So, which section of the signal path I should cut and connect to the switch?
Do I need the switch to be DPDT or i can use the current SPDT (which is the Bright switch)?
Any help will be greatly appreciated!
Here is the full schematic:
https://drtube.com/schematics/musicman/rd50a.gif
Side question: can I safely bypass the whole preamp by plugging directly into the return of the reverb tank and use the Reverb pot as a "master volume"?
Or, can I safely use the reverb connectors as Send/Return and the Reverb pot as Mix?
Although the amp is half tube, the preamp in question is solid state, so I'm posting here. 🙂
I'm trying to figure out how to safely add a "kill EQ" switch to the clean channel of this amp. In fact, I would like to use the "Normal/Bright" switch for this purpose, which is already there, because I never user use the "Bright" mode anyway.
So, which section of the signal path I should cut and connect to the switch?
Do I need the switch to be DPDT or i can use the current SPDT (which is the Bright switch)?
Any help will be greatly appreciated!
Here is the full schematic:
https://drtube.com/schematics/musicman/rd50a.gif
Side question: can I safely bypass the whole preamp by plugging directly into the return of the reverb tank and use the Reverb pot as a "master volume"?
Or, can I safely use the reverb connectors as Send/Return and the Reverb pot as Mix?
The first stage op amp make gain for the EQ control circuit, if you want to kill the EQ you have to cut the circuit in red color and add parts in green(connection in blue), after that you have to reduce the first stage gain to a suitable level(try change R2 220K to 100K to reduce half gain), if you don't use the "Bright" mode then no need connect that part.
For your side question, it seems work, but the stage gain is very high at the reverb tank input, you have to adjust the R31 470K by reducing it to a acceptable level for the whole amp, you can use a 500K pot for R31 to test the resistance value.
For your side question, it seems work, but the stage gain is very high at the reverb tank input, you have to adjust the R31 470K by reducing it to a acceptable level for the whole amp, you can use a 500K pot for R31 to test the resistance value.
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