Cafe Walter Audio

Can I brag a little? I’m feeling super proud of myself. This is the guts of a Strymon Flint, a popular but expensive reverb/tremolo pedal for guitar. Needless to say, schematics for things like this are not available; you can’t even trace the PCB by hand, because it’s a multi-layer board. But I figure, it’s basically a big DSP chip, a bunch of RAM, a few different switch-mode power converters, some control encoder buffering, an ADC, a DAC, and a bit of analog I/O, right? How hard can it be?

In hindsight it actually took longer than it should have... the TL072 that buffers the input was fried. The trick was, it wasn’t *totally* fried, it just had crazy high bias current, that was causing a protection diode to conduct enough to shunt the input signal. Enough signal was getting through to fool my troubleshooting.

The clue, that I initially discounted? There was a small DC voltage on the input.

In rehearsal with Degenerate Art Ensemble. I am so excited to be back in a theater again!!

Death cap from a Gibson GA15RVT that somebody worked on. They replaced all the caps (including, undoubtedly, caps that were perfectly fine) - but the soldering is atrocious. See how on this one they just draped the capacitor lead over the terminal and added a little solder? They didn’t even trim the lead! Other solder joints weren’t even joined at all.

I love working on old amps. I hate working on old amps that were “fixed” by hackers like this - it’s much harder to undo the damage.