Guitarists, do you bias your own tube amps?

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Vulture 420
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I bought new tubes for one of my amps last year, and about a month ago after working fine for a few days straight it blew the High Tension fuse and would no longer work without always blowing fuses. I figured out one of the tubes went bad by removing all the output tubes and then turning the amp on under load, seeing that no fuses blew. I put one tube in at a time, turning the amp on after inserting the tube. First tube, no noise, no blow. Two tubes, crack! Pop!, quickly back in standby without blowing the fuses. Replaced the second tube with another tube that used to be third in line, crack! Pop!, back in standby. At this point I figured it must be the first tube that was bad. I took it out, proceeded with the remaining tubes left to right one by one, no noise. Had an old set of tubes still from the last quad last year, chose one and put in in 4th position, and beautiful classic Marshall EL34 tone commenced.

This whole issue got me thinking, the last time I had tubes changed by an amp tech they lasted 20 years before one went bad. These I ordered and they lasted one year before one went bad. I double checked what i had ordered and they are actually EL34L tubes by JJ, quality Slovakian tubes but they are not the stock EL34, but EL34L, which I did not bias when I changed them. So now I'm thinking I should learn how to bias my next set of tubes while I see how long this mismatched set lasts.

I've watched some videos so I get that I need one or two multimeters, I need to know the max wattage of the tubes I get, which could be 25, or they could be 30-40. There is also a calculation you have to make to get the exact bias voltage target. There are tube sockets for about $16 with leads hanging off the correct pins for measurement available, so I'll probably start there as far as tools go, and I already have a multimeter. Looks simple enough that I won't have to deal with traveling to an amp tech when I get around to getting new EL34 tubes.

Sorry, I just checked my order, it was November 2 years ago, not last year. Ok, that's better I suppose for just swapping tubes with no care in the world.
Séamas Honorary Consul General
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Nope.
I don't have the courage to service my own tube amp.
I've never even switched out power tubes.
I know that before you do anything you need to drain the filter caps. I know a lot of guys who've been zapped by them.

I have been watching a lot of amp servicing on Youtube. Some really cool stuff--especially guys transforming old church and school PAs into guitar amp heads.
I'd really like to take a basic electronics class, I would REALLY like to build one of the Mojotone kids of an old Fender Deluxe.
I have ordered a Fuzz box kit. Waiting on some down time so I can wire that up--not in the same league as an amp but I need to start somewhere.
Vulture 420
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Yeah! I bet it's pretty easy to learn how to put together your own amp using a kit that is a clone of one of the classic designs. I always wanted to know what the amp building secrets are that take a standard Marshall from 1970 to the tonal elite range of the custom mods used by people like Billy Gibbons and amp makers like Mike Soldano. Just never had the time to get into it, I honestly have all my attention and time sunk into actually playing and learning more about playing the guitar. I suppose it could end up being an employable skill if I really got deep into it.

As far as draining filter caps, I just make sure I don't go touching them at all. The danger is if you have the amp removed from its box with the electronics exposed underneath (as you would when biasing), and you accidentally go touching the leads on those big blue capacitors which can hold about 500V. There is no danger in changing tubes in general, and if they sound worn and lifeless you're going to have to change them eventually.
Pithecanthropus Roast Master
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I don't. The bass player in my Eagles tribute band has been my gear tech for pretty much my entire musical life.
Vulture 420
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Pithecanthropus posted:
I don't. The bass player in my Eagles tribute band has been my gear tech for pretty much my entire musical life.

Do you pay him?
Metacell Chocolate Brahma
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I don't even mess with the equipment until something stops working. I just know how to play the guitar. I'd be totally lost if I had to make my own.
Vulture 420
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I dread having to mess with anything outside of playing the instrument. Yesterday I got a new pump bottle of spray polish because I ran out of the polish I've been using for the past decade or so, and I had to change the strings on my main electric and clean it. The only thing that makes it worth it is that it feels like a completely new and different guitar with new strings and no accumulated crud. Looking forward to plugging it into the newly working Marshall today with the pedal board to hear how it all is supposed to sound. The last thing I ever want is some minor guitar and amp maintenance to stop me from playing routinely and frequently.
-Don't poke around in electrical circuitry unless you have to.

-If you have to poke around, invest in high quality, reliable alligator clips so that...

-you only reach in to the circuit with one hand, while the other is not touching anything related to the circuitry or anything earthed. Clip your meters leads into place before powering anything up when that is feasible.

-current kills, not voltage. But touching a charged point with your finger will make you jerk away your hand and that's when you fall over off your chair and bang your head on something and die. So keep you work area clear and also avoid reaching in to areas of the chassis that have sharp edges so you don't tear your hand up. Alligator clips.
Metacell Chocolate Brahma
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This is especially true for anything with tubes in them, which are essentially high-powered capacitors and can have a logarithmic rate of voltage decay.
Pithecanthropus Roast Master
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Vulture posted:
Pithecanthropus posted:
I don't. The bass player in my Eagles tribute band has been my gear tech for pretty much my entire musical life.

Do you pay him?

Well, yes. It's his business.
Séamas Honorary Consul General
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Metacell posted:
I don't even mess with the equipment until something stops working. I just know how to play the guitar. I'd be totally lost if I had to make my own.

Vulture posted:
I dread having to mess with anything outside of playing the instrument. Yesterday I got a new pump bottle of spray polish because I ran out of the polish I've been using for the past decade or so, and I had to change the strings on my main electric and clean it.


Your basic solid body electric guitar is a pretty simple thing to maintain--especially the bolt-on neck ones. A semi-annual truss rod adjustment should be something most guitar players should be able to handle fairly easily.
There is a fun youtube site Dave's world of Fun stuff where he does set-ups and small repairs. In just about every episode he goes through a standard truss rod check. He also has several videos where he sets up bridges of the various types.

One thing he mentions frequently is the truss rod is adjustable for very good reasons: do it. There is sometimes more =danger in not ever making an adjustment as a bolt can freeze up. Even if it doesn't need adjusting, make sure it is operating every now and then.

Having some good knowledge of set up and basic guitar wiring can also be a huge asset when buying a used guitar: be able to see what is an easy vs costly fix can save a lot of money. Sometimes some "broken" guitars being sold cheap just need a couple hours of fixing--and on the other side, knowing to check whether a truss rod is operating or not can help one avoid a big headache.

Fret crowning, leveling and dressing is something I have yet to try. Largely due to some of the specialized files etc, can be costly.

Acoustic guitars are a different story. They definitely need more specialized care and close attention to humidity, temperature and changes of both.
I have one (a '53 Martin 00-17) with a non-adjustable truss rod.
I've paid as much in getting a neck reset than it would cost to get a pretty damned nice new one.

That said, I have in mind a new project for a '90s Tacoma DM-9 acoustic. The action has been rising and there is some crack in the back (and possible loose bracing).
I paid about $400 for it used. It has an excellent sound, and played beautifully for years.
Having the guy who did the work on my Martin work on it would be ridiculous. Fortunately, this guitar has a bolt on neck like a Taylor, so there is hope I can handle the neck rest myself. While doing this I can mend the crack and fix where any bracing is loose. I am considering sanding the body, giving it a gloss nitro-lacquer finish and giving it a new pickguard.

My other projects are refinishing and replacing the electronics on an old Aria Pro II bass. I am also going to craft a new pickguard out of sheet metal in a custom shape. I would like to apply a design into it via an acid bath etch. Also have removed the finish on the back of the neck and am in the process of burnishing it. I need to get a good good measurements of it --I am unsure if it would be possible to replace the neck with a Warmoth one. I would LOVE to make it fretless.
And the other is the fuzzbox I mentioned in the earlier post.
Vulture 420
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I actually watch Dave's funny setup videos a lot. I like when things get gooched. I also have to adjust my Led Paul truss rod 4 times a year just to deal with the seasons, the neck is very sensitive and very responsive like it should be to quarter turns. The Martin acoustic I have for over 15 years now I've only adjusted the neck maybe twice, it plays so well. I've had the upper bout side repaired after somebody cracked it when I wasn't around, and then my cat knocked it down and cracked the side in another place, that time I was able to glue and clamp it myself and it still sounds and feels great. I've never done a crown and polish myself but the Les Paul could use it after 18 years. When I was young and played an Ibanez I would get a crown and polish once a year, that guitar felt like garbage after you wore down the frets, but felt amazing when it was done. Now there is a special CNC PLEC machine in some big guitar stores that does the fret work better than any human can, that would be nice. It scans the neck with strings on and truss rod adjusted as best as it can be, then with strings off to measure the exact neck and fret positions and gets to work in fine detail. The machine requires somebody who knows how to get the best results out of the machine and costs about $150.
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Guitarists, do you bias your own tube amps?