Unidentified Magical Tesla Coil

[GasMask52]

Diodes don't usually fizzle. They just go open or short. It could be like Leo said and there's some contaminant on the board. Sometimes boards can go conductive with burn marks. Gotta clean all that or even remove the burns with a Dremel like a melon baller.

You got that right !! after I de-soldered the burnt diodes I tested them and they are fine, if I power the amp on with the guitar and speaker connected I get a low volume 8-bit-ish buzz that starts at a high frequency and slowly settles in a lower frequency, no output from guitar

[g1]

Resolder those caps, diodes, zener diodes and voltage regulators in that area. They are all prone to 'de-soldering' themselves due to heat and vibration.
It sounds like a bad solder connection at those diodes was arcing. What are the component designations on those diodes for future reference?

[g1]

Never mind, I found them. D2,3,4, & 5 in the HV supply for the tube. Top right pg.1 of attached schematic.
Check fuse F1, then check for high voltage at both sides of R19.