Cap job I did on a Bogner Shiva recently

[pompeiisneaks]

I mention in the video that I thought it's based on a marshall, but can't recall where I'd read that, anyone familiar with these?

I'd love to know more about them in general, interesting layout etc. Any comments on things I maybe missed or should have done different?

[davebolden44]

awesome man. this is why everyone hates pcbs. i have done this on my marshall 1964 and an orange, take loose the bear minimum, hinge it up and work on it like under the hood of a car.

[pompeiisneaks]

Yeah I didn't want to have to desolder all of those unless it was absolutely necessary.

~Phil

[billyz]

It really bothers me that this passes for amp tech work.
No diagnosis, no testing, waste of time and money.
I am glad I retired , too many wanna be techs .
And please tune your guitar.

[billyz]

I apologize. I was feeling cranky.

[pompeiisneaks]

Well, considering there was nothing I could see specifically wrong, and I've been counseled by many great techs that electrolytic lifespan in tube amps should never exceed ten to fifteen years and this one was at thirteen, I explained to the customer that some of the noise may be from the age of them. The amp sounded quite a bit quieter to he and I after. Not sure what else you can expect. I do appreciate the apology, and would love to have more constructive feedback on why my decision was bad.

[vibratoking]

What happened in this thread is interesting. From my perspective billyz wrote what was on his mind. He spoke his truth. Phil had a very civilized reaction and asked for constructive criticism. Good on Phil for not blowing up. I would have. And billyz apologized. Nice.

I agree with Phil. I would have ripped out those caps and replaced them based on audible noise and their age. Yes, you could diagnose them with any number of methods. Looking at ripple on a scope, measuring the caps value - capacitance, ESR, visual inspection, substitution. A scope could have been used to track down the source of the noise. All are viable approaches, but are they really worth it? For that amp, I wouldn't have bothered with those test until the caps were replaced and an issue still existed.

Phil - I have heard two clips that you posted. I agree with billyz, tune that guitar. I'll be honest, I quit listening as soon as I heard the first out of tune note(s). For me, all credibility and interest is lost at that moment.

My $0.02

[pompeiisneaks]

I know the demo of my AC30/4 was annoying, it was for me, I literally just tuned it seconds before playing and it went out, it's a newer guitar to me and obviously somethings amiss with it, as it can't stay in tune well.

OTOH, I don't stress it much normally when I'm testing an amp. I just want to hear that the guitar makes noises and hear if there's some horrid buzzing/sounds still coming out.

Thanks for your input too, though, I will definitely try to make sure the guitars I use in videos get tuned so it won't irritate

I'm definitely glad to hear another person agrees with the 'age' thing. Everything I've been told is that once they get much past 10 years, swapping them out is a smart choice because they're at the age that they definitely are adding noise to the amp, AND they're liable to fail at any point anyway.

Many caps have only a 2000 hr rating at their max temperature (105c in many cases) and in tube amps, if not put in a smart location, they can really get up near that heat range. The caps cost like 18$ in parts or so, and I charged him another 20 for the hour or so it took me to do it. I also educated him that there wasn't a guarantee it would fix the issue, but since I saw nothing else wrong, it was at least a starting point.

We both agreed it sounded cleaner and more bright after the replacement.

Maybe we're both imagining it.

[M Fowler]

If you watch Mr Carlson's lab he is one heck of a tech and he is always talking about how bad those caps are which he replaces immediately.

I do agree more testing is needed following a cap change to determine the function of the amp but I'm not an amp tech, can barely turn my scope on verses trouble shooting with it.

The videos have value to certain people and I would not discourage you from making more amps or videos.

Good to see you back on TAG BillyZ your knowledge is welcome.

Mark

[pompeiisneaks]

I have watched a lot of his video's, I'm always trying to learn more about the process. Thanks for the feedback. I know I need to know more, and am happy to have knowledgable people around to share

~Phil

[billyz]

I apologize again. Now I am embarrassed even. Woke up on the wrong side of the bed.
I should not second guess your decision.
Farty sounding. I would have first tested the tubes, even substituted and biased first. Crappy speakers can get farty. Too large of a coupling cap can be farty. As a tech who tried and made a living at it, I am not a fan of doing $20 labor jobs. But I realize many are enjoying this as a hobby these days.

I know it is the buzz to do a cap job as a fix all. I have been doing some Solid State Vintage Receiver rebuilding and the Big Buzz is the same , CAP job.
Funny though, those 70's japanese caps are still strong, don't leak and test spot on.

I thought about deleting my post, but think I should leave it as a reminder to myself.

[davebolden44]

Aside from the technical/non technical approach of simply changing caps as noise solution, the video has value demonstrating the nightmares of repairing almost any pcb. I hate em.

[pompeiisneaks]

billyz, I am fine with the original apology, I understood no offense was intended.

I definitely get that sometimes things can be misinterpreted, but I don't take offense initially because I've been burned myself by email/text/board misunderstandings.

I definitely value learning from anyone, and I'm not just trying to be a hobbyist. I've spent a year dedicating all of my spare time to learning to build amps from scratch and understand how they work. I've released videos almost every week for over a year showing my learning process. I also am not far from you on the west side of the state, so if some chance meetup happened, I'd welcome it. I'm also a bit older myself, and have been around the block a few times, I'm always looking to learn, and grow. I think that the only way to get there is to dedicate a lot of time to all aspects, and I make it clear in the videos as well that I'm open to input on how I could do things better.

I did a pretty thorough look over of the amp for obviously damaged components, or problem areas, and found none. I'm drawing a blank right now, but I swear he told me that he had just replaced the tubes, or that he had tubes to replace in it, but I told him that tubes would be the best first swap option. Upon discussing his options, he chose the cap job after I could see nothing else wrong. I am not sure that's the perfect solution, but I've got a happy customer, and I felt I learned in the process.

I definitely don't like working on pcb's either. I have my own fender blues deluxe I've worked on ('95 or '96) and I hated that thing, the damn ss reverb resistors baked the bottom but luckily I didn't lose any traces. I've debated saying "I'm not touching pcb's with a 10 foot pole'

~Phil

[billyz]

I would happily meet up with you.
I promise to be good.

Z

[pompeiisneaks]

Heh, so then I just need to figure out if I'll be heading that far east or if you're heading out to the big city

I've heard by my brother in law who lived there for a while, that there's a great Pho place there.

~Phil