rule of thumb: how long do you leave a tube preamp on versus turning it off then back on?


I just upgraded to an Audio Research REF 10 with 12 tubes and I am wondering how to best preserve the tubes. How long sitting turned on is equal to the wear and tear of turning it off then on again? I had a Rogue RP 7 with just four tubes so I didn't worry about this issue so much, I just turned it on when I began to listen then off at the end of the evening. Now I'm wondering where the sweet spot is? Away for a hour, two, three, turn it off when? Am I over-thinking this issue?
wokeuptobose
Post removed 
The longer it's on the better it sounds. If you paid what you paid for your amp in order to get good sound, why would you then shoot yourself in the foot trying to save pennies on tubes? 
Thank you both. I'm over thinking it as just after I purchased my REF 10 I saw the forum comments here a couple days ago about ARC equipment blowing tubes, and the further comments about how the guy couldn't
get it to be reliable. So he felt he needed to go to a Pass preamp. That is just the kind of story that gets my over worrying mind busy!!
For me solid state never turn off.  For tubes turn off after usage.  I have 16 300B tubes in my mono amps alone plus another 8 rectifier tubes.  That can add up in my mind.  

I suggest that you call AR and do what they tell you.  This question comes up frequently and advice is all over the place on it. 

I'd also start saving up for a set of replacement tubes.  Not that you need to worry about them, but it will be nice to have the money set aside when you do need them.
30 min turn on for me, prior to listening intently
20 minutes warm up for me including turntable does the trick. But, it all sounds so much better after about 6 hours. Turn off when done. Best not to leave powered up tube gear unattended.
+1 @ millercarbon

HOW DO I KNOW WHEN MY TUBES NEED REPLACING?

Power tubes like EL34’s and KT88’s are good for about 2500 hours or more. But may go longer in an amplifier with a conservative design. Small signal tubes with numbers like 12AX7, 12AU7, and 6922, and rectifier tubes like 5AR4 may go 10,000 hours. So you get years and years of enjoyment. Using a tube tester may or may not tell you if you need a replacement. The best approach is to buy a new set of tubes, and install them. If they don’t sound a lot better, put in the old ones and suck every bit of life out of them.




Use and enjoy what you paid for, you knew that tubes wear out.
Just power them off at end of each session. It is not wise to leave them on and be away for some time. Normally a tube will last longer in hours if not switched on and off but a year has approx 9000hrs so you will need replacements at least twice a year if left on all the time. Otherwise with normal use replacement would take place every 2-3 years.

G

Best not to leave powered up tube gear unattended


important advice, to be heeded, by @noromance -- better safe than sorry - even for preamps, i have seen tube rectifiers go up in smoke
after burn in (Brent Jesse advised 60 hours on, no signal needed)

then: on, 20 minutes, magic, off. preamp and amp 
Nobody leaves tube on turn on 1/2 hour before listing.HELLO!!
Good grief! You are fortunate to own this level of gear-enjoy it. Turn it off whenever you’re done, turn on when ready to listen again...simple.

Cut back on reading audio forums to reduce neurosis.

Cut back on reading audio forums to reduce neurosis
+1


 I had a Rogue RP 7 with just four tubes so I didn't worry about this issue so much, I just turned it on when I began to listen then off at the end of the evening

so do the same thing with the AR.
I don’t think a question about preserving the tubes is neurotic at all. It’s a simple question which aims at good habits to preserve a resource.

Without over-thinking it, the better you match your listening time with the time the tubes are on, the longer they’ll last. That will give you the confidence to spend more on better tubes, rather than changing them out more often. If you find that estimating this is a pain, then just turn them on and forget the conservation thing; you'll get more pleasure that way.
Tube gear sounds better as it warms up and operates and so does solid state gear so the longer you listen and leave it on the better it will sound. Cartridges are especially like this too they usually require between 4 and 6 album sides to sound right especially a low output moving coil.
@wokeuptobose Past three tube amps both used and new, with new or NOS tubes -    

Startup:  
During initial burn in, with new tubes in my preamp and mono amps, they performed and sounded better after 45-60min of warmup.  All burned in now, right at 30 minutes or so they seem to start sounding pretty good. Takes less time now, maybe 20-30 min, transformers too.   

Shutdown:
If the tube amps and preamps are on, and I know I'm not going to sit back down and do any serious listening for the next 3-4 hours, I'll go ahead and just shut them off.

As others noted, prefer not to leave them unattended for too long.   

Very interesting dilemma. 

I have a similar set up. 

I have the Ref 40th anniversary, similar to your Ref 10. 
My rule of thumb which has worked for me since I've owned it. 

1.  I turn it on after I turn on the rest of my system, but before the Boulder amp. 
2.  I turn it off 2nd, after the Boulder. 
3.  I turn it on about 1 hour before I venture to my listening room.  I turn it off after each session.  I usually listen every night or other night for about 1-3 hours. 
4.  I keep track of the hours with the tube counter.  At 2000, start thinking or planning on replacing the tubes.  
5.  Give it enough head room to breathe.  Do not stack.  

How do you like your Ref 10 btw?
My setup is a bit less exotic, an AR SP20 pre amp with a Ref 75 running KT150's.
I turn it on and just start enjoying it. No pre-listening warm-up. After about 30 minutes, it sounds noticeably better.
When I am done with my listening session, I turn it off, pre amp first, then the power amp. 
When starting it up, I reverse that sequence and first turn on the amp. Then the pre amp. 
I have always been leary of letting tube gear running longer than the listening time, and am careful to make sure the same start-up and shut-down sequence is consistently followed. 
Hope this helps!
On my Vinni Rossi L2ise which uses Takatsuki TA-300B  tubes at $1,500 a pair in the pre-amp section (which runs tubes more gently than in most amps) I turn on an hour before use as I can tell the improvement in sound quality, then leave after session on if I will be listening again in a few hours. If wife is away and I will be listening off and on all day or weekend, then I leave on and can tell it gets even better after 24 hours.
Funny. I'm old enough to remember when TVs and radios only had tubes. We turned them on and off numerous times and left them on for hours at time. Never remember having a TV  or radio go bad due to a tube failure. Maybe a poor comparison but we are a neurotic group and tend to over think things a bit.

J.Chip
Some of these comments are mistaken.  All gear has an optimal operating temperature; it does not sound better after it reaches that temperature.  
I don’t have an answer to OP’s actual question, but I thought I would restate it since so far most have answered other questions instead of what they asked.

What duration of time left on is equivalent to the wear of start up for tubes?

If you leave the room for 5 minutes it clearly makes sense to leave your tube equipment on. However, if you are done for the night and going to bed and probably won’t be using your tube equipment for 12 hours it makes sense to shut it down. What about the times in between? Most days I can listen for a little while in the late afternoon and then again late at night. For that average 2 hour gap I wonder exactly what OP asked. Do I leave it on or shut it down? I usually turn off tubes but leave on SS. I’m sure it would be heavily tube and equipment dependent. Some tube types are more tolerant to startup and some equipment is kinder.
For that average 2 hour gap I wonder exactly what OP asked. Do I leave it on or shut it down? I usually turn off tubes but leave on SS. I’m sure it would be heavily tube and equipment dependent. Some tube types are more tolerant to startup and some equipment is kinder.

That’s why it’s always best to call the amp’s manufacturer and talk with them about your listening habits and get their advice as to when to leave it on or turn it off. What somebody on Audiogon might have done doesn’t really help much.
Keep mine on for about 15 to 30 minutes, prior to listening....its a tavish phono preamp with small tubes of the 12ax7/12au7/5751 variety. These tubes have a much longer life span than the larger power amp tubes. I will usually turn off preamp soon after listening, although I sometimes procrastinate and its left on for an extended period of time, not too worried. 
sewolla
... When I am done with my listening session, I turn it off, pre amp first, then the power amp.  When starting it up, I reverse that sequence and first turn on the amp. Then the pre amp ... and am careful to make sure the same start-up and shut-down sequence is consistently followed.
The best practice is to do just the opposite. If you turn on your preamp first, any noise it might send to the amplifier won't matter, because the amp is turned off. Otherwise, the amp could amplify any turn-on transient. The same applies in reverse - if you power off your amplifier first, any transient that might occur when you turn off the preamp won't be amplified. I realize you're not having any problems in your system, but you might want to rethink your practice anyway.
When I’m done listening for the day, everything goes off and goes back on an hour before for warm up.

all the best.

JD
... When I am done with my listening session, I turn it off, pre amp first, then the power amp. When starting it up, I reverse that sequence and first turn on the amp. Then the pre amp ... and am careful to make sure the same start-up and shut-down sequence is consistently followed.
The best practice is to do just the opposite. If you turn on your preamp first, any noise it might send to the amplifier won't matter, because the amp is turned off. Otherwise, the amp could amplify any turn-on transient. The same applies in reverse - if you power off your amplifier first, any transient that might occur when you turn off the preamp won't be amplified. I realize you're not having any problems in your system, but you might want to rethink your practice anyway.

i agree w cleeds... power amp on last, off first

it has the big power to hurt speakers connected to it if there are any spurious transients introduced by other components turning on or off
+1 cleeds, +1 jjss49

Amps on last, off first.

Waiting 30 seconds between preamp & amp too. Some may wait longer. This seems to work on my tube amps, preamp.
Unlike SS, which can take several hours to sound their best, tubes amps, preamps get there within an hour in general.

My old SS system took 3-4 hours to just start sounding its best...depending on ambient temperature. And this with a tube preamp/SS amp.

An advantage of an all SS system is that you can just leave it on.

I let my tube system warm up for 2 minutes before I listen. Then I don’t worry too much about what record I listen to first. My system (Don Sachs preamp/Evo 400 poweramp) usually hits its stride at the last track on the first side of an LP.

So about 20 minutes for me...not even close to an hour. So I’ll often listen to B side first.

Then off after I’m done listening.

My guess is that you'll naturally figure all this out after some time with your system.



SS takes days to sound its best. Days. With tubes it is more like hours. With records there is the motor. When you hear improvement across the first side of a record, that's why. Try turning it on, spinning the platter an hour or so. There will still be some improvement, but not nearly as much, and starting from a much higher level. The difference is the motor - and controller circuits - being warmed up. 


Follow the rule of thumbing thru
your Owners Manual if they still
provide owners one. My guess
is it has a tube warmer that stays
on regardless. They will say 5-10 minute warm up.
Right?
If you live in Texas turn if off!
Consider that most failures, tube or solid state, occur when turned on.  This is do to the physical distortion inside the devices as they heat up.  In both cases it is due to thermal expansion and contraction in the material that are heated.  I remember the story of the oldest working light bulb being back stage in theater on Broadway in New York, it was only off when the city power failed so there were very few turn-on.

This would suggest that a slow power up would extent the of the devices.  Perhaps simply putting a light bulb in series with the power line with a  bypass switch for on, the bulb would restrict the current to the unit keeping warm but not hot until wanted to use it. 

It is more complex than that but this should start your thinking
But does not excuse my typos and spelling.

I leave my gear on 24/7, the only time I turn it off is during thunderstorms or if I'm going away for an extended period. I have a tube preamp with separate power supply it has 4 tubes. The reason I don't turn it off is because I use a big krell amp with it, which would take to long to warm up. I've had the same nos ken rad 6sl7 tubes in it for over 3 years.
@sandemallI also have Don Sach tube preamp and Pass amp. If you leave on your SS, don’t you worry about your preamp tubes blowing while you’re turning it on/off?
@sandemallI also have Don Sach tube preamp and Pass amp. If you leave on your SS, don’t you worry about your preamp tubes blowing while you’re turning it on/off?
I’ve owned tube preamp for 25-30yrs now. Do not worry about your tubes, they will last a lot longer than you think. I use mostly expensive highly sought after vintage tubes in my preamps and in all these yrs, only 1 tube has went bad. I use 20 tubes total in my 3 main preamps. AR SP11 mk 2, Marantz 7 and CJ PV5.  When I’m listening to one of my systems, I turn the preamp on about 12 noon and do not turn it off till 12 midnight.  I have 3 tube testers in house, and like I said, all these yrs, only 1 tube went bad. Whatever system you want to use to “save” your tubes is fine, but the point I’m making, don’t worry about them so much, they’re gonna last a long time in your preamp unless 1 or 2 fails. 
Thanks to everyone for their thoughtful answers. The general gist of things as I summarize your comments in my mind is that common sense should prevail and to turn the preamp off when I'm done for the day, clearly stop worrying about tube life and enjoy the system. The REF 10 does have a 12 volt trigger turn on and off feature as do my Parasound JC1+ amps. This may somehow be audiophile heresy to make use of such a convenient feature, but I love it and with the REF 10 start up mute and delay sequence it seems to work very well.
 I was also asked how I like the new REF 10. I absolutely love it, its less" tubey" than I expected, strikes a great balance between the classic tube and SS sound (so did my Rogue RP7), imaging and depth are great, and I've never had a preamp that didn't seem to change the sound as I changed the volume. I literally get lost as to where I am with the volume level. I will notice that sometimes I am listening at a relatively low or high level without choosing the level numerically, just enjoying the music.
Finally, like many of us, I wonder if I had this or that component would I enjoy my system more. At this point, I don't have any desire to try any other preamp, and that my friends is a wonderful feeling! I hope it lasts!!
Thanks again for the insights!
I have had the exact same thoughts as you, OP.  I read through the posts and didn't feel anyone actually addressed your question.  If I am hearing you correctly, this is the scenario.

You have had your stereo on for whatever amount of time listening and your family wants to watch a 1 hour show, so you have to decide.....do I leave everything on and go watch the show and then come back and hit play or do I power it all down and then power back up an hour later.  

Which is harder on the tubes, an hour of idle time or the power cycle?  

I understand the incentive for sound quality, but I too don't know which is harder on the tubes regarding their life.  

It seems that many electronic components in our lives are more stable when left on constantly vs repeated power cycles.  

Seems we are both over-thinking and should just leave it on for reasonable amounts of idle time.


Yes, thank you for reframing my exact question! I think no one may actually know the answer because there are too many variables for a "rule of thumb" guideline. Lots of well intentioned responses. I'm going to turn it on a little before or concurrent with my listening, and leave it on the rest of the day, turn it off when I head to bed. Done! I'm over it!! Thanks!