Originally Posted By: Guitarhacker
Man that thing sounded really, really good..... for about 30 seconds or so.... them it started getting really distorted and the sounds started getting wonky and I noticed the output tubes looked like light bulbs.... oh my.... I don't think they're supposed to be glowing that brightly....

This is one of the factors why I didn't try to make too much comment from my boat. I'd want to do the research.

Most amplifiers of this kind operate in what's called "class-B", in which mode the amplifier dissipates a similar amount of heat to the output power it's delivering and that dissipation is what makes the valves (or transistors) get hot. It's likely where your glow came from, though there are other possibilities.

BTW, Billy, I doubt that any kind of zener would be suitable to drop the voltage for your EL84s ... If you want to use those, you should try to find a suitable power transformer with appropriate winding voltages.

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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