Recent content by Voodoo Guitar

FYI the Tubedepot adapter socket + NOS JAN 6U8A tube fit & sound great for about $20 total!

That was it... replaced and everything is running fine! Still planning to try the 6550s, but it sounds great with 6L6s right now. Thanks for all the help!

I did the bias cap as well as the 1k 2w dropping resistor... the 10k 5w was still spot on. Hopefully those 100ks will solve my bias issues, as the 56k & 47k all read fine.

I'll be checking and likely replacing them as well as the 2w 100k in the bias circuit. Almost thought my meter was broken when i saw that bias current reading.

Yep thats them. I suppose I could clip them off, or just stick with 6L6s or maybe KT66s. Also, just noticed something that i can't believe I missed... my 6l6GCs are showing 117ma on the bias probe. No redplating, and they sound pretty damn good (until that 7199 PI noise starts), but i know...

any tips for removing those 7027 retainer clips?? I have a nice pair of 6550s i can't wait to try. Sounding pretty good with 6L6s right now.

Thanks for the great info!! Just tried all of that... cleaned socket contacts with deoxit, tightened with screwdriver, reflowed solder on all pins... seemed to help with the inconsistent filament heating, but the noise still starts up after a few moments of playing. Damn shame, since it sounds...

Thanks for all the tips guys! I stuck with the NFB off the 16ohm tap and left the dummy load resistor alone. Powering up, all the voltages look good after a recap with 6L6s for now. I'm afraid the 7199 PI tube is shot... first it wasn't lighting up at all, then after a reseating it worked fine...

Just wired up a switch with one speaker jack, since that's what I had handy... question re: negative feedback and dummy load, i should be able to move them both to the + lead on the speaker jack at this point with no issues, rather than both coming from the 16ohm tap directly, eh? Ideally i'd...

I'm not too worried about resale, as the $500-600 these go for is nothing compared to the personal value of this having been my dad's amp since day 1 out of the store. It's an heirloom... a very large, heavy, smelly heirloom.

I may just remove it entirely, as I think I'll redo the output connections (remove original 4-pin XLR, add 16/8 switch).

Looks like mine are still good, barely any drift, so i'll leave em. the 250 ohm, looks like that was used as a failsafe in case the amp was turned on without a speaker, or just using the preamp put jack?

ah, i think i got it... i was looking for a rectangular wirewound like yours, but mine is kind of a hollow ceramic tube, never saw one like that before.

Hey all, i'm restoring an original B25 and getting lost in the convoluted circuit board... mainly, I can't find a few of the components! The 10k 5w & 47k near the 40uF filter caps don't appear to exist on this amp. Also, the "death cap" was actually mounted on the main board, which I found...

Cool, thanks for that... just updated.