Yeah, sealing my nerd fate with that title, I know. I found some 10W resistors my dad had given me years back and threw together a quick resistive load. Unfortunately I can't seem to take decent pics of the 'scope with my phone so you'll just have to take my word for it that Bodie makes a solid 27.5W RMS before distortion. In guitar advertising speak that's probably 35, hell, 40W.
The high frequency response is, well, excessive. Like 30 kHz excessive. That's over two octaves higher than even the brightest guitar speakers will reproduce and a good half an octave higher than humans can hear. I really should've checked the low frequency response.
There's a tiny smattering of intermodulation distortion at very high volume - not surprising considering that I used small filter caps. This results in the occasional ghost note but the ghosting is faint - hard to notice unless you're looking for it and often hard to reproduce. I could chase it out with bigger reservoir caps, but the sag is delicious and I'm not designing this bad boy for high gain so I'm just going to leave that alone.
I also poked around a bit and looked at the signal as it arrives at every grid. The paralleled input stage and the second gain stage are almost exactly center biased. The third stage is just a hair cold, so everything's where I want it to be. The third stage is the first to break up, which makes sense. I might attenuate a little more here to get the 2nd and 3rd gain stages to break up closer to each other... I probably won't, but it's a good excuse to try out both channels on the 'scope.
Cathodynes get a bad rap for distorting awfully but I slammed this one and couldn't see any nipple distortion or frequency doubling at all. NONE AT ALL!
There is, of course, some crossover distortion. Hello cathode biased output section. I'll investigate the zener trick of course, and maybe even the Paul Ruby mod, but the amp's not buzzy so it doesn't really matter. Gotta be careful not to become an oscilloscope hypochondriac.
Man, that would not make a good band name.
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