How Often Do You Retube?

[clayfeat]

It has been a few years since I swapped out the tubes on my Delta Blues and I have been wondering if there is a rule of thumb on when it is time to retube.

The amp still sounds great so maybe I should just wait until it doesn't sound so great? What do you guys/gals think?

[ac15]

Originally Posted by clayfeat

It has been a few years since I swapped out the tubes on my Delta Blues and I have been wondering if there is a rule of thumb on when it is time to retube.

The amp still sounds great so maybe I should just wait until it doesn't sound so great? What do you guys/gals think?

You may be unaware, because tube wear occurs gradually, but the amp is already suffering tone-wise. I can tell without hearing it, because tubes are like strings: they get progressively worse, but you just don't notice it unless the amp is squealing, hissing, or plain doesn't work. It may not sound "bad" but if you haven't changed tubes in a few years, it probably doesn't sound as good as it could. You need new tubes, unless you rarely play the amp. If you play a lot, they say at least change the power tubes once a year. I think you can go longer with preamp tubes.

Having said that, I don't always practice what I preach. I've got at least one bad preamp and/or power tube and the amp is making some funkyass sounds but I've been putting off making the change, biasing etc. I know it's time though.

[woodman]

it's hard to state a general rule, because all tubes are not created equal. NOS tubes tend to last longer than current production ones, IME. if it were my amp and it still sounded great, i wouldn't worry about it til warning signs pop up (microphonics, noise, power/tone loss and so forth) ... but i always carry a full complement of replacement tubes for my amps every time i play out, just in case one tanks during the gig.

[1293]

Never. I have a Musicman I bought in '85 or '86 that still has the tubes it came with.

[DH82c]

my understanding is that preamp tubes get replaced when they go south/micro.
Powertubes are different and should be replaced "regularly".
Ok.. "regularly" is a user discretion term. How often do you change strings? Some people change them once a week if they need to or not. Some people NEVER change their strings (even if they REALLY need to). Tubes are similar. Some people change power tubes once a year. Some people change them when they break.

[Jakedog]

If I am using an amp as my main amp, I change power tubes once a year "whether they need it or not". I always notice a difference in tone afterward. Like the above poster noted, you don't always notice the degradation because it happens so gradually. But if you play more than 4-6 hours a week at any kind of volume, I'd say a change is in order, and you will most likely notice a difference. I always do.

That said, I keep my old tubes as spares. Unless they are completely shot, or have obvious issues (red plating, storming, shorting, etc.) I use them as spares. A pair may be a bit worn, but they will still get me a through a gig in a pinch. Then I can buy another new set when time and money permit.

[bokeh]

I've had an orange twin combo for a while now; I've changed the power tubes a couple of times but figured it would be best to leave the preamps alone. Should i change those after a couple years or so? I play a ~2-3 hours daily

[Jakedog]

Originally Posted by bokeh

I've had an orange twin combo for a while now; I've changed the power tubes a couple of times but figured it would be best to leave the preamps alone. Should i change those after a couple years or so? I play a ~2-3 hours daily

I don't mess with pre-amp tubes unless they start acting up. If you notice them going microphonic, swicth 'em out. This can usually be diagnosed as the problem if your amp starts making ticking, pinging, rattling, hissing, noises it wasn't making before, or if it starts feeding back and/or squealing more than it should. I've found a bad pre tube usually starts as something that sounds like a chassis rattle, but a high pitched metallic sounding chassis rattle. You'll spend all day trying to find it until you realize it's one of those pesky pre-amp tubes.

[mlove3]

I change em when they die or clearly have lost their oomph.

ac15, please send me all your old bad tubes. Please don't throw them away. I'll pay shipping. I'm serious.

[cowardm]

Specially if this is your main amp, I wouldn't be concerned by overall tone (although I suspect it has declined) as much as reliability. Because of that you may want to at least change the power tubes (and have them biased). As for preamp, I certainly don't think it would hurt. This is also your opportunity to put in some tubes more honed to your tastes. If so, you'd do well to familiarize with preamp tube types and brands of power/preamp tubes.

[strat a various]

Some tubes last longer than others, some amps are harder on tubes. Since you should have a spare set, can't hurt to change out the power tubes, see if it sounds better. I play 6-7 nights a week and my tubes last years.

[detuned]

Change them when you start to think about selling your amp.*Then* you'll remember why you bought it in the first place!

Or if one fails/goes microphonic.

:-)

[ac15]

Originally Posted by mlove3

I change em when they die or clearly have lost their oomph.

ac15, please send me all your old bad tubes. Please don't throw them away. I'll pay shipping. I'm serious.

Even though I preached the importance of regular tube changes, like I said, I don't always do it myself. I'm definitely overdue for a tube change but have been putting it off.

As for sending you the tubes, unfortunately I only throw them out when they are microphonic or don't work at all. You probably wouldn't want those. As long as tubes work, I keep them in case I need them in a pinch.

[zoppotrump]

i go the same way as "woodman".
i play as long as they sound proper. and i always carry a set of replacement tubes to gigs.
as for my dr. z maz jr. , due to the fact, we gig a lot and plus the regular rehearsals, i have to change the power tubes every 1 1/2 years.

[varakeef]

Originally Posted by 1293

Never. I have a Musicman I bought in '85 or '86 that still has the tubes it came with.

I'd give it a thought already. My friend just fried his Musicman because of the failed power tube. It cost him 70 euros extra in addition to tube and the fried transistor.

[stantheman]

My '56 Champ has ancient Tubes.
I only fire Her up on Sundays.

[Hiker]

When they need them, or if a 12AX7/12AT7 is way out of balance.

Case in point-I bought an expensive Hickok tester. Two reasons, it tests in ways that most emissions testers don't (gas, life, mutual conductance); and it is going up in value as I write this...