Help: Designing ax84 P1 Extreme Based 2 Channel Amp
I'm thinking of building a 2 channel amp based around a P1ex. I built a P1ex already, and loved the tone. My electronics skills are good, but I am still a little new to tube amp theory so I need some guidance.
Here's what I want to do:
1. Add a clean preamp channel. I assume this shouldn't be that hard, but I need a few pointers to get me going. I want it fairly clean, but maybe some bluesy breakup when cranked. I assume this will have a fixed gain right?
2. Add an effects loop. This should be trivial, right?
3. Add a parallel octal/ noval setup for the poweramp. basically put 2 master volume controls, each feeding 1 tube, with each tube having it's own bias circuitry and such, but both leading into the same OT. I've seen this done before, so it should work.
I have a few questions for #3 though. Will this change my transformer needs for the primary impedance, and if so, how? The B+ voltage in a P1ex is way too high for an el84, so what do I need to change to knock it down for that tube? can I tap into the part of the power supply running the preamp tubes and beef up the power supply resistors for the extra load?
Some links: P1ex docs
Parallel output done in an HO build (lower B+)
Thanks for the help in advance. Any pointers are welcome. this should be a cool build.
I'm thinking of building a 2 channel amp based around a P1ex. I built a P1ex already, and loved the tone. My electronics skills are good, but I am still a little new to tube amp theory so I need some guidance.
Here's what I want to do:
1. Add a clean preamp channel. I assume this shouldn't be that hard, but I need a few pointers to get me going. I want it fairly clean, but maybe some bluesy breakup when cranked. I assume this will have a fixed gain right?
2. Add an effects loop. This should be trivial, right?
3. Add a parallel octal/ noval setup for the poweramp. basically put 2 master volume controls, each feeding 1 tube, with each tube having it's own bias circuitry and such, but both leading into the same OT. I've seen this done before, so it should work.
I have a few questions for #3 though. Will this change my transformer needs for the primary impedance, and if so, how? The B+ voltage in a P1ex is way too high for an el84, so what do I need to change to knock it down for that tube? can I tap into the part of the power supply running the preamp tubes and beef up the power supply resistors for the extra load?
Some links: P1ex docs
Parallel output done in an HO build (lower B+)
Thanks for the help in advance. Any pointers are welcome. this should be a cool build.
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