Tube Amp Archive

Well, as someone who owns a couple of vintage Supros, that sounds Supro-ey AF. Nice!

I hit an online auction a while back from a local hearing aid test equipment company that was moving manufacturing overseas ( :cry: ) and bought a lot of three of those multi-drawer electronics parts boxes. By the look of things they were from three different workstations, mostly 1/4w resistors with...

Also possibly relevant is the reason 51 ohms would be more common than 50... https://www.electronics-notes.com/articles/electronic_components/resistors/standard-resistor-values-e-series-e3-e6-e12-e24-e48-e96.php The idea behind the standard E values is that every jump in value is the same percentage...

Further head-scratching and option-mulling. This is why I don't get anything done: I have a tendency to dedicate a ridiculous amount of time to thinking these things over. It's not that I think I'm smarter than Ampeg's engineers, it's that I have a different set of critera: different components are ...

I'm reasonably sure I'm keeping this once I get all the bugs ironed out. I've got a ton of various low wattage stuff, mostly vintage - a couple of old Supros, my early Silverface Princeton Reverb, A Marshall Artist (weird but cool in its own right - like they took the power section of a 50 watt JCM8...

Yep, you're seeing exactly what you think you're seeing there. I think it might be a manufacturing defect... it seems insane that the tube could get hot enough to dimple like that while still running!

Well, a little more snooping around on google images. I found a pic of an amp that has the resistor on the cap can, and this pic of the same amp... with nothing on the board at R53. https://i.imgur.com/6xU5KdP.jpg?2 I think we can put that one to bed... this is what happens when you have holidays de...

I'm waiting on the rest of the electrolytics to really dig into this, but tracing things out I ran across something that has me a bit confused. There is a 3K 10 watt ceramic resistor on the preamp cap can in my amp. I've looked around the net and it appears to be original, since I see the same ceram...

It would be a cool toy, but I can just imagine the results if such a tester became common. You'd spend the rest of your life wading through threads titled, "Is a 2.3% mismatch in gain too much to run in my Boutique-O-Drive Gain Master 60™?" :roll: I can't say its necessarily the right approach, but ...

Yeah, apparently Google Photos doesn't really support remote image hosting. I moved them over to Imagur - hopefully they'll cooperate.

Thanks for the tip. As hot as this thing has obviously been, I'm planning to give it some judicious chopstick poking when I fire it up on the bench. After that resistor came loose in my hand, I'm not really inclined to take too much on face value. My suspicion is that it was a bad solder joint to be...

Okay, the title is a bit dramatic... It's not on the verge of anything at this point except having some parts replaced. Anyhow, everyone loves a good origin story, right? Anyhow... I spotted this VT-40 on Seattle Craigslist for $200... Master volume, non-distortion. It was described as having issues...