Guardians of the analog
Papi Fuego
- Build Rating
I would have liked to had the time to make a demo with this but between work and the kids after school sports I spend my time catching up on yard work and other adult chores the 3 nights a week I am home. The past 6 weeks I spent the little free time I had building, testing and fine tuning this amp and it's finally done and all put together. Last November I built this same amp pcb and built a JCM800. That was my first amp build and while I learned quite a bit it felt more like building a pedal in the sense that it was more paint by numbers. This actually came about during one of @MichaelW and I's conversations on gear and tone chasing. He had gotten a Friedman IR-D and was gushing over it and I started looking into it and after a deep dive through schematics and tracing I learned that it's a modified JCM800. Also it works equally well with humbuckers and single coils. My stock 800 works best with humbuckers and the bright cap makes single coils sound harsh. So I decided to buy the bullet and build my own dirty Shirley.
This go round I had to make a fair amount of changes to the amp in both the preamp and the power section. The preamp is the same in both the full size and mini version of the amp so that was pretty straightforward. The power amp and power section is sort of a mashup of both versions. I used 5881s like the big amps, but it's cathode biased like the small amp. I used 22n coupling caps in the PI like the mini because anything more and the amp felt too mushy at higher volumes. I tested all my guitars for weeks at various gain/volume levels with different values in various areas of the amp to fine tune it to my liking. This really paid off. Also the Friedman master volume voltage divider on the mini version of the amp is fantastic and very good sounding across the whole range of the knob. No more attenuator for me.
So how does it sound and compare to an 800? It's like a great cross between a JTM45 and an 800. It's got more dynamics, better response and not as stiff as an 800 but not as loose as a JTM. With the treble tweaks of the amp I have full range of all the EQ knobs. The presence is also the old style 5k presence pot and is much better than the linked 25k pot. For the push pull Jose style clippers I went with 24v zeners. The V2a cathode has a push pull 680n bypass cap to focus the mid presence and help tighten up higher gain. Finally the gain pot has a stock 10k cold clipper and a high gain mode with parallel 3.3k/680n to really push the gain. V1&2 share the same B+ power node which gives more compression, sag and touch response like a JTM. The mid slope knob is useful in getting even more tones out of the amp. The zero loss transparent effects loop also means I can use all my time based pedals and never have issues with them
I went with Amplifyfun and Spencer knocked it out the park with my designs. I wanted this to really be MY amp so I designed an amp badge to resemble the old Marshall square logo. The front panel and badge are brushed stainless silver with black engraving. I named it the Feral Cheryl after my wife, who's middle name is Cheryl. This is the tone I have been searching for. Now all my pedals and guitars are back in the rotation. This can do everything from big bold cleans to straight nasty and everything between with guitar volume and tone knobs. I can not recommend this project enough. Now I go back to playing and maybe a pedal will inspire me again one day.
This go round I had to make a fair amount of changes to the amp in both the preamp and the power section. The preamp is the same in both the full size and mini version of the amp so that was pretty straightforward. The power amp and power section is sort of a mashup of both versions. I used 5881s like the big amps, but it's cathode biased like the small amp. I used 22n coupling caps in the PI like the mini because anything more and the amp felt too mushy at higher volumes. I tested all my guitars for weeks at various gain/volume levels with different values in various areas of the amp to fine tune it to my liking. This really paid off. Also the Friedman master volume voltage divider on the mini version of the amp is fantastic and very good sounding across the whole range of the knob. No more attenuator for me.
So how does it sound and compare to an 800? It's like a great cross between a JTM45 and an 800. It's got more dynamics, better response and not as stiff as an 800 but not as loose as a JTM. With the treble tweaks of the amp I have full range of all the EQ knobs. The presence is also the old style 5k presence pot and is much better than the linked 25k pot. For the push pull Jose style clippers I went with 24v zeners. The V2a cathode has a push pull 680n bypass cap to focus the mid presence and help tighten up higher gain. Finally the gain pot has a stock 10k cold clipper and a high gain mode with parallel 3.3k/680n to really push the gain. V1&2 share the same B+ power node which gives more compression, sag and touch response like a JTM. The mid slope knob is useful in getting even more tones out of the amp. The zero loss transparent effects loop also means I can use all my time based pedals and never have issues with them
I went with Amplifyfun and Spencer knocked it out the park with my designs. I wanted this to really be MY amp so I designed an amp badge to resemble the old Marshall square logo. The front panel and badge are brushed stainless silver with black engraving. I named it the Feral Cheryl after my wife, who's middle name is Cheryl. This is the tone I have been searching for. Now all my pedals and guitars are back in the rotation. This can do everything from big bold cleans to straight nasty and everything between with guitar volume and tone knobs. I can not recommend this project enough. Now I go back to playing and maybe a pedal will inspire me again one day.
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