Had to reset my password as I've been away for like, 10 years. Anyway, I've built several amps over the years but none since 2016. A stereo version of the Sunn Sceptre, just the power amp section. I use it as a pedal amp with an Fractal Audio AX8 as the amp models. Sounds great. It's basically a Dynaco 35 watt, but I used a 100 watt power transformer and Train Wreck OT's are good for likely 40 watts. It's can get loud and clear. Okay, enough of that.
Current project: I want to build this time, the full circuits of the amps in question, and feed back from the forum is desired. However, the first hurdle I've got to jump is: What output tubes are possible for my design? A friend gave me a Fisher 500-S Stereo Receiver that looks to be in really good condition. The Iron looks immaculate. It seems to be a 30 watt/channel amp using tubes compatible with the EL84 Tubes. There are two filament taps that I'm believing I could, parallel phase compatible for the necessary filament taps to power EL34's; Something about miss matched impedance reflects the right primary load if this is an 8k primary OT. The output voltage of the PT is 385 volts with a two diode rectifier. A full bridge should generate a higher voltage and, this is a 60's PT so the voltage is likely higher present day. It's been a while since I built an amp so I could be wrong. First question. Can I run EL34's with this Iron?
Fisher Schematic Link: https://www.fisherconsoles.com/non%20co ... 9%20sm.pdf
So I'm thinking I want to build two amps and run stereo. An 18 watt based on JMPGuitar circuit, and either a JTM 45 circuit or possibly a Train Wreck Express as the other. Some of the time I'll just plug the AX8 into the power amp section. Other times, I want to be able to drive both channels to get a two amp mix.
Any ideas on where to go with this? Best regards, and thanks for any help.
Silverfox.
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