That is GORGEOUS. Zoomed in it looks like most of the components just have black heatshrink over them, but a few (notably the larger electrolytic caps) look like they may have been painted? Either way a killer look. I think this should be the standard instead of gooping circuits you don't want traced.
Hmmmm.
Putting heatshrink on resistors in a hi-voltage amp doesn't strike me as the best way to manage heat.
The resistors shouldn't be dissipating much heat to begin with, if the resistors in your tube amp are getting hot enough to worry about managing heat then you have a problem.
I have to agree.
The only resistor that might get hot is the power stage cathode resistor, and maybe the b+ resistors. All the others are normally rated for 1W but will have a really low dissipation. For example, let's say the plate resistor drops 200v at a 1mA current (12AX7) it will only give you 200mW. Normally the voltage drop and currents are way lower.