The high cost of not knowing how to change your own tubes in an amplifier


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So I went to Goose at GWorx in June 2019 to get my Diezel amp serviced.

He replaces all the tubes, not just power amps, preamp tubes too.

In February, the amp stops working. I tell Goose it is the preamp tubes, he asks me to bring it over. I also wanted to get my Mayones modded, so I take that to him too.

When I give him the amp, he says it is under warranty in person, though I don't have it on messages. After all, he replaced every single tube. This in February.

Nearly two months later, I haven't heard anything after asking him once. On April 3, I ask him what is up and he gives me the ultimatum to let him work on the amp and a guitar I had given him or just take it back.

As you all know, things have gotten bad because of Covid-19, so today (April 4), I went to Goose's shop and asked for my stuff back.

He promptly replaces two of the power tubes in the amp. It's still not working. Then he changes a preamp tube and it starts working. Were the power tubes actually bad? He didn't even do any biasing, just plugged in new tubes.

I then get a heart attack as he proceeds to charge me for this all. Remember, I paid him $519 at the end of June for new tubes and my amp had been at his shop for two months,

Lesson learnt, I need to figure out how to do this stuff myself. $165 is a lot of money to me in the current economy.

I don't even know if it was necessary to change all the tubes last time. Or whether he actually changed the tubes, as he never gave me the old ones back.

Preamp tubes do not fail in just six months. That's bullshit.

Oh, and I mentioned a guitar I gave him for modding? No work done, and this is the condition I get it back in.

Definitely wasn't like that before, though I have no proof.

Am sad, but I figure guitars get dinged all the time. I'm definitely not going into his store again though, will learn how to do this stuff myself or go to TYMC or something.

Most likely do it myself. Ugh, such a bad feeling about the guitar and being ripped off on the amp. $45 for a no-biasing, "I'll fit the tubes right in" service.

Good luck giving him anything, that's all I'll say.
Just an FYI. The amp has stopped working in under three days. Going to file a consumer complaint against Goose, there are laws against this kind of thing.

it's a good thing I have records of all my transactions.

That's a $4500 amp, I'm heartbroken. I'm now wondering whether the damage to the guitar was intentional, given that the amp is not working. I'm not even sure he's been giving me new tubes, maybe just some shit he had lying around his shop.
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So in my first post, you'll notice that Goose charged me for a matched quad of JJ power tubes.

I looked in the amp and checked the tubes. No markings. Just four plain single EL34s that he charged me a $180 for. Or at least, it isn't apparent to me that there is any marking after checking the tubes. No left, right written on the tubes, nothing.
I filed a complaint asking for all my repair fees to be refunded.

I have a question, when you buy a quad matched set of tubes, shouldn't there be some kind of numbering on the tubes or something, like if you buy a matched pair and it says left and right or whatever?

Here is the JJ power tube he gave back to me that he removed from the amp. I checked all the other tubes in the amp and they are identical. No markings or anything.

Hey there.
Have been in your shoes once before. My amp was eventually fixed although it was tampered with from the earlier shops that did them.

Tube amps are
Just more
Sensitive to temperature and all sorts of electrical component failures that eventually lead up to tubes glowing as they burn up or struggle to retain a positive current through the amp.
Then it’s a new blow up altogether. For the matched pair, you’re right. They come in rated on their boxes. The ratings can be a pen mark or a marker pen or sometimes even a sticker.
Met some guys that run their amps at full tube ratings and some at other preferred limits. We all have our own preferences.

Wish you the best in picking up self-repair path for your gear...
JJ tubes are quite reliable for their EL34s after years,the only shortcoming of this brand is the filaments sometimes get blown off due to the filaments material quality.
Tubes amp dont just give probs,it may happens sometimes but again this is more of how good the quality of the amp being made,modern tube amp parts made from PRC never had the same quality as like the vintage US or UK made can last for decade and still work like a horse!
Most guitar amp are auto biasing which need to replace the tubes in matching,groove tube do sell them in matched pair but again after years they will mismatch due to working life spend hours.Tube amp needs maintenance just like any mechanic machine.