Tube life question

[Trouble]

I have no answer for you, however I DO notice my amp (current Marshall, and I think my former Vox AC15 too) seems to (have) sound(ed) better after being on for a while. As in, it sounded o.k. after I warmed it up and flicked off "standby", but sounded amazing after I had been playing for an hour or so and went to put the guitar down. It made me want to, well, never put my guitar down and just keep playing!

 

I am not sure why, and not sure how wide-spread it is, but to some extent I seem to find the longer I play a tube amp the better it sounds. Kind of like the more beer you drink the better it tastes. It could help explain the "put it in standby for an hour then play" because, for one they might notice it sounds better, as well as the "more is better" mentality (i.e. if waiting a couple of minutes for the tubes to warm up is good, waiting five-to-ten is better, and waiting an hour after you mow the yard, take a shower, and eat a sandwich to flip off standby must be sensational!, the proof being how the amp actually sounds better when you do it!!!).

At least I'm not the only one who noticed this. another thought that had crossed my mind is that it might also be my ears adjusting to the way the amp sounds. Sort of like a concert is loud at the beginning your ears become accustomed. I guess that would be back to the myth thing though huh?

[JeffB]

What brand of tubes were in the amp originally and what brand did you replace them with? I've read articles which said that some tubes will last that long, but in my limited experience, have never had that kind of tube life.

They are Fender branded tubes from the 80's so what ever they were using back then.

Also just remembered I did cook one of the 6l6s using it in a mesa I had.

Im thinking they were probably a better quality tube back then.

Having said that I just dont have problems with tubes like other people seem to...or I havnt yet. I seem to get really good mileage out of them. Except groove tubes. I dont know why, any amp I buy with GT's seems to need to have a tube replaced pretty soon.

[blackjack]

When you turn on standby and power switches at the same time, the power tubes can’t conduct because the heater hasn’t been able to warm the tubes. This is the case for the 90% of the amps that use direct-heated rectifiers, and SS rectifiers.

 

What’s it mean? You’re putting over 700 volts on the plates of those tubes for a second or two as it begins to settle (allow 30 seconds). Roughly, 100 to 200 volts over max rated. You get away with it because the tubes handle voltage stress better than current or power stress. But it’s not free: it actually punches holes in the electrolyte of the main filter caps. And they heal themselves in time, but they’re getting beat up, affecting noise levels and bass response. I’m starting to sound like Seinfeld`s car mechanic who steals the car because Jerry leaves the AC on when he cranks it. Would you do that! (I’ll bet so).

 

Turning a volume pot? They only ever see AC signals, and that’s completely independent of all of that discussed above. Kind of logical, but no way. OK, rant over.

 

I did mean to add, that I'm glad kbp810, tulk1, Steiner, NoNameBand, and others are here so consistently to add good info. I need to get out more.

[tulk1]

My Classic 30 doesn't have a standby switch, but I'm thinking of having my tech put one on to do away with the "pop" on powering down..Is that a bad idea?

I wouldn't think so as it serves to protect the life of the tubes as well as prevent power surges through the speaker which can also damage the speaker voice coil.

 

Except it was designed to not have a standby switch. Hartley isn't a dummy when it comes to designing amps. He hit the mark with the C30 design. I thought about adding one to my Delta Blues. My amp guy said it wasn't necessarry. I'd have preferred to have one, but he said no.

[tulk1]

If you've ever noticed, touring amps/bands, power up their amps at least an hour before the gig starts.

I power my amp up at gigs as soon as I can. Sometimes before I have the PA set up. Got to get them tubes HOT!!!

[NoNameBand]

They are Fender branded tubes from the 80's so what ever they were using back then.

Also just remembered I did cook one of the 6l6s using it in a mesa I had.

Im thinking they were probably a better quality tube back then.

Having said that I just dont have problems with tubes like other people seem to...or I havnt yet. I seem to get really good mileage out of them. Except groove tubes. I dont know why, any amp I buy with GT's seems to need to have a tube replaced pretty soon.

Groove Tubes are made at and by the old Sylvania company I believe in Kentucky. To my knowledge, these are the only remaining American made tubes. Kbp810 is very knowledgeable about tubes and could suggest well made contemporary or NOS tubes.

[kbp810]

I believe that GT only makes their own 6L6's; the rest are tubes that they've tested against their own metrics and then re-branded as GT tubes.

 

Someone please chime in if I am wrong though... it's been a while since I've done my homework on Aspen Pittman!

[tulk1]

I believe that GT only makes their own 6L6's; the rest are tubes that they've tested against their own metrics and then re-branded as GT tubes.

 

Someone please chime in if I am wrong though... it's been a while since I've done my homework on Aspen Pittman!

From the TubeStore

Groove Tubes is not a tube manufacturer. Neither' date=' for that matter, do Fender (who now own the Groove Tubes name), Ruby Tubes and a host of other companies manufacture tubes. All of these companies simply re-label tubes from the same factories we buy from: the companies who actually build tubes, such as New Sensor (who make Electro- Harmonix, Sovtek, Svetlana, and re-issues of Mullard and Tung-Sol tubes), JJ Electronic, Shuguang, SED and a few other factories.[/quote']

[JeffB]

From the TubeStore

tubestore said:

Groove Tubes is not a tube manufacturer. Neither, for that matter, do Fender (who now own the Groove Tubes name), Ruby Tubes and a host of other companies manufacture tubes. All of these companies simply re-label tubes from the same factories we buy from: the companies who actually build tubes, such as New Sensor (who make Electro- Harmonix, Sovtek, Svetlana, and re-issues of Mullard and Tung-Sol tubes), JJ Electronic, Shuguang, SED and a few other factories.

Ive known this for a while. But three amps Ive had with GT's in them at purchase have all had tube failure early on in the relationship. Its either been a couple of 12ax7s or a 6L6. I know every company has a fail rate but Ive only seen it(had it happen to me) in one particular brand. Not a statistic to base any thing on. Just an unhappy coincidence for me.

[kbp810]

From the TubeStore

The 6L6GE is a GE Reissue that they make in house here in the US - everything else (including other 6L6 variants) are re-branded

 

From "The Tube Amp Book"

[DetroitBlues]

When I was at The Cult concert last year, the warm up band had two fender twins turned on well over an hour before they played. Didn't matter because they sucked. Didn't flow with The Cult's music at all. I usuallu allow about 5 minutes more before I play.

[Guest HRB853370]

I don't play in a band, so my playing time is very inconsistent. Sometimes multiple times a day. Would i be better off to power up the amp and leave it on standby all day or turn it on and off each time I go down to play?

 

What would be better on the tubes and the amp as far as being less wear and tear?

 

Thats a tough question. I have the same problem you do, so what I do is play through my TransTube Peaveys when I want a quick fix. I realize I am not enjoying the creamy tone I get from my tube amps, so when I feel like playing or practicing for an extended period of time (not multiple times in one day), I just fire up a tube amp (always power ON in STANDBY MODE and power DOWN in STANDBY MODE). If I have to go get a beer or use the bathroom, I just switch the amp to standby, then when I come back, switch back to power mode. I would logically think that the more the tubes are left on (even in standby mode) the quicker they will wear out. Of course leaving them on in full power mode will definitely shorten their life. Do you have a SS amp?

[bolero]

I remember a long discussion about this on the Ted Weber ( RIP ) amp forums a long time ago

 

 

some of the hardcore tech guys argued that what wears out power tubes is the heating/cooling cycles, not just constant use

 

so they recommended NOT using the standby switch when you take breaks, as it cools & then reheats the power tube elements...the heating/cooling expands & contracts the metal structures inside the tube, which wears them out faster than just leaving them on

 

 

I don't think I've ever heard of anyone actually testing this & getting stats....you'd think the tube mfr's would have the correct info though