My first amp return... let's make it right. 

I bet you could stuff those astrons.

🙏 Thanks!

We were going for the all original look in the amp, but I get it. To make it VERY clear in the doghouse there's a note saying they're stuffed with Sprague pointing to my YT channel to see the work done.

@@YeatzeeGuitar Yup - understood. And if that is what the amp owner wants - that's the way to get there. It's just never been a concern of mine, but I love stuffed Poblanos🙂 You are doing good work and explaining things well. The guitar and amp world is a funny one. People want their guitars reliced and their amps to look new. I'm holding my ratty tweed Fenders until reliced amps become a thing.

@@brianmccowan1949 fender has done relic amps in the past! Nothing cooler than a ratty tweed imo

I like that trick!

It's a compromise of course, in the same way keeping old carbon comps are a compromise. They're going to have a tendency of being noisier, and more fickle plus natural resistance drift. Why not just gut the amp and replace every single one with metal oxides? It'll be far more reliable right..

I honestly think they'll be fine, it's going to get some long testing this weekend to confirm it's showing no signs of anything and I'll be using those tubes to be sure. So far though, they've been rock solid. Those old 5881's are tough.

@@huddyskiba1 I haven't seen anything about those in a while. Would be great, I tried stuffing one and it shattered. Super fragile and brittle.

Do not!

ESR (equivalent SERIES resistance) does not apply in this situation. Of concern is Insulation resistance (PARRALLEL or Shut resistance). Generally in tube amps (with linear power supplies) ESR is not a huge problem and measuring unknown electrolytics can be misleading without a reference measurement. Modern e-caps likely have low ESR and lower than vintage types even when they were new.

Also, "Pyramid"-brand capacitors. And then there are the Bumblebees.....😖

The handwired? No I sold it a while back

I typically bias fenders cooler than 70%. Closer to 60% is more my preference. The first bias measurements were with my own set of matched 5881's.

@@YeatzeeGuitar whose brand of 5881's were you using?. i only ask because some techs claim for certain 5881's (jj;s probably) 460pv.is beyond whats comfortable.. if they robust, sovtek's etc you should be ok.. i think the schematic for the super 6g4-a circuit which I think is what you had calls out 450v W 5881's.. iv'e used the russian 6p3s-E which is a ruggedized 5881 im using them in a 5f6a @ 415 pv & have heard some say 475 pv = no worries..

@@Gorilla.Guitar Vintage. Yeah this era bigger amps used 5881's all with plate voltages in that range. Concert is another one, probably even higher than this. I'd sooner just go to modern 6l6's if using a new tube.

@@YeatzeeGuitar been chasing this stuff as a hobby for few years, just my own stuff. theres a lot of good people in the community that have a wealth of knowledge to share. which is how i stumbled upon your channel. you definitely have your customer service skills on point I believe you claim to be relatively new at it (?) most have good knowledge but the techniques can vary. which is what I try to determine. pay attention & remember the good ideas. you most likely know what You Tube channels are worthy but i'll pass 'em along just in case *Uncle Doug*.- great channel mostly restores hand wired fenders, great explanation, concise, expert level repair. i've actually catalogued a lot of his content that i didn't understand at viewing time & have gone back to for clarification... Psionic Audio- good stuff, more variety in brands & types of repair. his personality is a bit ogre-ish but he's a wealth of knowledge as well.. then there's the guitologist.. have a fire extinguisher handy for that one. keep up the good work!

​@@YeatzeeGuitar, Tungsol 588I's from the 1950s were purportedly designed during the Cold War for the military, to drive the servo motors for bombsights on planes. The originals are extremely rugged, and can certainly handle more than their official 430v, 23 watt rating. Modern Russian and Chinese tubes are another matter entirely.

You're not wrong, spoiler alert but the problem aint fixed!

I agree. Attention and testing needs to be done under dynamic conditions. Confirm the PI is balanced with in reason. Also severe blocking distortion can cause red plating. PI to speaker and back through inverse feedback loop is all suspect till you prove the failure mode and at times it's helpful to open the nfb loop when troubleshooting so you have a linear direction of circuit so to speak, to work with.

Bypass caps = stuffed, coupling caps obviously are original and untouched. I've only ever seen one person stuff yellow astrons, I tried once and it was too brittle and fell apart.

Thanks Matt. Stay tuned, next video there's a little mini comparison of jupiter vs mkt. Too expensive to but all the former, but owner was curious so he bought two to try.

The electrolytics were already swapped with Sprague, they're just stuffed inside the original shells..

Those blue moldeds are the same age and fine. But thanks for the nice comment.

There always has to be one jerk, sad! Like Tanner said, blue molded caps are almost as old and usually test fine. Before you post an ignorant comment, learn your amp stuff cause you just showed you know nothing about amps. Tanner, please ignore people like this. Love the channel, can't wait for the next video!