How long do tubes last and how do you preserve them?

[Asterix]

How long might my 2 (used) EL84's and 1 (used) 12AX7 last in my MG HEAD Mark III headphone amp? Is it better to turn it on and off as much as possible to preserve the tube life or is this worse for the tubes?

 

[sacd lover]

Quote:

Originally Posted by Asterix How long might my 2 (used) EL84's and 1 (used) 12AX7 last in my MG HEAD Mark III headphone amp? Is it better to turn it on and off as much as possible to preserve the tube life or is this worse for the tubes?

No one can answer how long your tubes will last without doing a life test on your tubes. As far as turning the tubes on and off; use moderation. Leaving a tube on all the time wastes the tubes lifespan. Turning the amp on and off frequently is hard on a tube too. Turn the amp on awhile (15 minutes to an hour) before you listen and turn the amp off once your certain your through listening.

 

[Hirsch]

Tubes do wear with use. However, the single biggest stressor on the tube is the on/off cycle. Some people feel that this is a big enough problem that they leave tube equipment on 24/7. I disagree...BUT I don't like turning tube equipment on and off a lot either as that WILL reduce the life of tubes. My compromise is to turn an amp on once, on a day that I'm planning to use it, and to leave it one until I'm done. I turn it off at the end of the day. This may or may not be the best plan, but it's the one that works for me.

 

[ReasonablyLucid]

Quote:

Originally Posted by Hirsch Tubes do wear with use. However, the single biggest stressor on the tube is the on/off cycle. Some people feel that this is a big enough problem that they leave tube equipment on 24/7. I disagree...BUT I don't like turning tube equipment on and off a lot either as that WILL reduce the life of tubes. My compromise is to turn an amp on once, on a day that I'm planning to use it, and to leave it one until I'm done. I turn it off at the end of the day. This may or may not be the best plan, but it's the one that works for me.

Thats what I do. Except I listen to my headphones nearly all the time.

Turn it on when I wake up and turn it off when I require sleep.

On days that I work I turn it off before I go to work (2 on/off cycles those days).

 

[GoRedwings19]

Quote:

Originally Posted by Hirsch Tubes do wear with use. However, the single biggest stressor on the tube is the on/off cycle. Some people feel that this is a big enough problem that they leave tube equipment on 24/7. I disagree...BUT I don't like turning tube equipment on and off a lot either as that WILL reduce the life of tubes. My compromise is to turn an amp on once, on a day that I'm planning to use it, and to leave it one until I'm done. I turn it off at the end of the day. This may or may not be the best plan, but it's the one that works for me.

Sorry if this is off topic but I read your post with great interest. The problem I have is that I have a musical fidelity tri-vista sacd player. I read that they bought all these stock of tubes up and they have one spare for each tri-vista component. What I would like to know is are there any alternatives???? I listen to it all the time throughout the day. But it is worrying that after these tubes run out then Mu-Fi have a spare set and that's it. Do you have any thoughts on this? Thanks

 

[sacd lover]

The tubes in your player are very long lasting; like 100,000 hours. These tubes were designed to be something like a transistor/ tube hybrid. I dont believe MF has them all either. I saw some online somewhere. Give me the tube # and I will check for you.

Quote:

Originally Posted by GoRedwings19 Sorry if this is off topic but I read your post with great interest. The problem I have is that I have a musical fidelity tri-vista sacd player. I read that they bought all these stock of tubes up and they have one spare for each tri-vista component. What I would like to know is are there any alternatives???? I listen to it all the time throughout the day. But it is worrying that after these tubes run out then Mu-Fi have a spare set and that's it. Do you have any thoughts on this? Thanks

 

[GoRedwings19]

Quote:

Originally Posted by sacd lover The tubes in your player are very long lasting; like 100,000 hours. These tubes were designed to be something like a transistor/ tube hybrid. I dont believe MF has them all either. I saw some online somewhere. Give me the tube # and I will check for you.

Hey this could be fun tuberolling the tri-vista!!!! Some nice amperex pq's

 

[GoRedwings19]

Quote:

Originally Posted by sacd lover The tubes in your player are very long lasting; like 100,000 hours. These tubes were designed to be something like a transistor/ tube hybrid. I dont believe MF has them all either. I saw some online somewhere. Give me the tube # and I will check for you.

According to google when I did a search it is 5308 Oops read it wrong it is 5703 according to most websites

 

[Asterix]

Can someone tell me how long a good tube will last in my amp? If the tube is new? EL84's? 12AX7's?

 

[john_jcb]

Quote:

Originally Posted by Asterix Can someone tell me how long a good tube will last in my amp? If the tube is new? EL84's? 12AX7's?

It is impossible to predict as others have stated. I have tubes in an amp from the early 60's that still work great. 40 years is not bad. Others may fail within days or weeks.

 

[sacd lover]

Quote:

Originally Posted by GoRedwings19 According to google when I did a search it is 5308 Oops read it wrong it is 5703 according to most websites

Radio Electronic Supply/www.vacuumtubes.net/ (800-326-4140) has your 5703 tube listed for $6 each.

 

[drminky]

I have the trivista dac. Don't worry about the tubes (raytheon 5703WB to be precise). As stated you can get them all over the net for next to nothing. Don't believe the MF marketing hype re them buying up all these tubes. I've read all sorts of marketing babble about them being built to be used in ICBM missiles (they don't fry like solid state does after the nuclear EM pulse or something to that effect), but AFAIK, they were built to be used mostly in microphones. Hence their very linear response, small size and low power output.

As far as tube life goes, preamp tubes (12ax7, 12au7, 6992 etc) are usually supposed to last 10,000 hours or so (around 5 years @5hours/day). Power amp tubes (845, EL84, 300B etc) tend to last considerably less than that. I read somwhere that tubes will last approximately twice as long if left on continuously. So, I tend to do as everyone else here does, turn them on an hour or so before a listening session, and turn them off at the end of the night. If I had the time to listen more than 12 hours a day, I would just leave it on, but for me its more like 3 if I'm lucky!

 

[Rob N]

Quote:

Originally Posted by GoRedwings19 Sorry if this is off topic but I read your post with great interest. The problem I have is that I have a musical fidelity tri-vista sacd player. I read that they bought all these stock of tubes up and they have one spare for each tri-vista component. What I would like to know is are there any alternatives???? I listen to it all the time throughout the day. But it is worrying that after these tubes run out then Mu-Fi have a spare set and that's it. Do you have any thoughts on this? Thanks

The tube leads in the TriVista are soldered directly to the circuit board.No tube sockets.

 

[gaijin]

Quote:

Originally Posted by john_jcb It is impossible to predict as others have stated. I have tubes in an amp from the early 60's that still work great. 40 years is not bad. Others may fail within days or weeks.

How can you tell when there is a failure ?

 

[john_jcb]

Quote:

Originally Posted by gaijin How can you tell when there is a failure ?

As the tubes wear out both bass and treble response suffer. This occurs gradually over time and these differences are hard to notice. I think sometimes the differences people hear when tuberolling may be partly attributable to comparing tubes that are degrading with new or new old stock ones. When a tube dies completely you may notice that it stops playing altogether or degrades significantly depending on the design.