General PSA for anyone who owns a tube amp

MadAsAHatter

MadAsAHatter

Well-known member
Most of you who do their own basic maintenance probably already have one, but for those who don't...

Anyone who owns a tube amp should invest in a tube tester. It doesn't have to be fancy or expensive, but it can pay for itself in saving a trip to the tech.

Case in point. For a wile I've only owned one tube amp so it wasn't a big deal to pay a tech to do some basic maintenance. In the last several years I've acquired a number of tube amps that a trip to the tech for routine maintenance on every one would add up quick. I got a bias meter a while back so I could start doing my own biasing. About a week ago I finally got around to getting a tube tester. I bought an EMC 211; cost me just over $100. It's fairly basic but does what it needs to do.

Went to play my Crate Stealth earlier today and no sound. Everything looked fine on a visual inspection. Putting the tubes on the tester I found 2 of the preamp tubes were pretty much dead. Replaced them with fresh ones, it fired right back up and I was back to rocking out. So it's already saved me a trip to a tech and probably about $100. Definitely worth the investment and has already paid for itself.
 
Tube testers are notoriously inaccurate, I've never seen the point of owning one. What upside do you feel owning one has vs just swapping out the tubes if you suspect they're dead? I just keep spares on hand and do the pencil test on tubes. Never let me down.
 
Try to do everything myself. Was raised that way. Passed it on to my kids. Money saved is money earned in a way. Between my husband and I, the only thing we pay anyone else to do is install car tires as that's more of a pain than the cost of equipment or voiding tire warranty. Also, *insert "the more you know" space rainbow. Engine swap? check. Computer repair? check. Plumbing, electrical? checkity check. Life $$$ add up quick. Money that instead gets put into our kid's "now that you're 18, gtfo fund." :ROFLMAO: half kidding of course; It mostly goes to gear. They can get their own damn haircuts and jobs!
 
mooncobra said:
Cesar Diaz how to be amp and guitar tech video

Look at the 49 minute mark and the light bulb test. There are some interesting things in this.



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This video looks almost like it was converted from VHS, haha. But, yeah he's got the info on the lowdown. Cesar reminds me a bit of bizzaro Bob Ross or something though.
 
MatrixClaw said:
Tube testers are notoriously inaccurate, I've never seen the point of owning one. What upside do you feel owning one has vs just swapping out the tubes if you suspect they're dead? I just keep spares on hand and do the pencil test on tubes. Never let me down.
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I have a 1960s Mighty Mite I paid 50 bucks for about 6 yrs ago on eBay. The main reason I bought it was just simply to make sure the tubes I bought were good, so I didn't install a dead tube and have a bigger potential problem. I've bought a lot of used but strong tubes over the past 10 yrs; and more than a few showed up dead. Mine tests for shorts and leaks as well as telling you how strong it measures. 120 is usually new; and most of mine test over 90. 70 is minimum good.
 
I’m completely happy having bought maxi matcher tube testers. I test every tube before it goes into my amps. You’d be shocked how mismatched tubes are from reputable dealers.

Also, I buy tubes like this, so I need to test.
1678069336285.jpeg
 
Why buy a possibly inaccurate tube tester when you can pop in another set of tubes that you should have on hand anyway? Tubes really don't need to be matched, and they weren't for a very long time. Remember, all of your favorite older album tones were recorded with tubes that weren't matched :p

Edit: This was kinda-sorta-not really tongue in cheek. I'm in an odd mood....
 
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I honestly don’t even want to think about tubes, it gives me stress. I have a backup set of each tube and when my amp stops working I’ll change them
 
sahlomonic said:
Tubes really don't need to be matched, and they weren't for a very long time. Remember, all of your favorite older album tones were recorded with tubes that weren't matched :p
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With output transformers, the coil geometry causes this imbalance. Only exception would be toroidal transformers, and you don't see too many builders using toroidal OTs.
 
sahlomonic said:
Why buy a possibly inaccurate tube tester when you can pop in another set of tubes that you should have on hand anyway? Tubes really don't need to be matched, and they weren't for a very long time. Remember, all of your favorite older album tones were recorded with tubes that weren't matched :p
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wasnt this started as a marketing thing by some company in the 90s?
 
MatrixClaw said:
Tube testers are notoriously inaccurate, I've never seen the point of owning one. What upside do you feel owning one has vs just swapping out the tubes if you suspect they're dead? I just keep spares on hand and do the pencil test on tubes. Never let me down.
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sahlomonic said:
Why buy a possibly inaccurate tube tester when you can pop in another set of tubes that you should have on hand anyway? Tubes really don't need to be matched, and they weren't for a very long time. Remember, all of your favorite older album tones were recorded with tubes that weren't matched :p
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It aids in the diagnosis of any issues. Why start off by replacing a whole set of tubes if you're not even sure that's the problem. It'd be better to do a quick test first.

Or why blindly trust a seller that those NOS tubes you just bought off Reverb aren't a box full of duds. Even new production quality is questionable at times. Or would you rather find that out the hard way?

I'm no expert on tube testers, but I know they're not fully accurate. And I'm not trying to match tubes either. Then that's not what they were designed for; at least the old consumer grade ones weren't. An emissions tube tester can at least tell you if there's a short and give a yes/no answer if a tube has some life in it. And as I just mentioned, I'd rather check a set of tubes first to know they're good than stuff them in the amp and fry it.
 
70 Mach 1 said:
whats the matter numb nuts are you tired of fighting with me.?
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Not looking for any friends asshole.
You just brought up a good memory.
Our corner place was a Utopia around Easter time cause they'd get all the chocolate stuff in.
And they not only tested tubes but actually stocked a good number of the popular ones.

If you want to fight some more let's do it over in the other thread instead of stinking up this one.
 
sahlomonic said:
Why buy a possibly inaccurate tube tester when you can pop in another set of tubes that you should have on hand anyway? Tubes really don't need to be matched, and they weren't for a very long time. Remember, all of your favorite older album tones were recorded with tubes that weren't matched :p
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Because throwing a tube in, that’s shot can possibly take a transformer with it when it arcs. Hopefully the fuse goes first but what if it doesn’t?
I’ve never cared about matching, ever..as long as my lowest tube is within 10ma of my highest in a set I’m good. For me, I like the peace of mind knowing that the tubes I’m about to bias in my vintage Marshall are good, and won’t take out (possibly) a transformer. I’ve had to return at least 12 tubes that were supposedly ‘good’ but showed up dead, thanks to my tester. If I put those tubes in and trusted them to be good, a disaster might have ensued
 
How (and how often) do you go about getting your testers calibrated?
I seem to remember reading that they should be checked often for drift,
but that would have been a long time ago and maybe that's not the case anymore.
 
DemNuts said:
How (and how often) do you go about getting your testers calibrated?
I seem to remember reading that they should be checked often for drift,
but that would have been a long time ago and maybe that's not the case anymore.
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Mine has a meter, that when set to calibrate the needle needs to align with the last number position. If it doesn't, there's a small bias screw-like dial that you can adjust so it aligns correctly.
Mine just tests for strength, leaks, shorts...not matching.
 
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