Leave tube amps always on?

@ jjss49
The Rogue Model 88 is an older amp. I bought it used. Not long after that, I had a problem and notice the ceramic (?) resistors had cracks in them. Rogue ran me through some checks using a digital ohm meter and at least one was bad. They sent me a bunch of replacement resistors and I soldered them in myself. Pretty easy. I then had a problem with a channel in my Rogue Model 99 pre amp which I sent in for repairs. They only charged $125 which is their bench fee because the parts weren’t expensive. I also had to replace the bridge rectifier in the Model 88 Power Amp at least twice. I did that myself also. Then, I had a problem with the power amp sounding very distorted/scratchy in both channels and would just blow both channel fuses. Sent it in. Rogue replaced some resistors and when I got it back - same thing. I then replaced the entire complement of tubes and still no help so I decided not to spend more money on it and put towards a new tube amp. Shipping the amp wasn’t cheap either. I also have two solid-state amps but I like my tube amp the best.

As the OP, I started this weekend - turning amp and preamp on Friday after work, leaving on, and will be turning off later today Sunday. During the week, will turn on and off normally.

Its probably in my head, but it sounds better today than the past two days. 

Such a fuss over a simple idea that’s backed by listener experience. Argue if you will about how much is costs to turn-on/off, replace tubes, etc. people who leave their gear on report better sound in the first hour or so. That’s the complete nut.
We’re mostly at home now. Why not leave your system on for a week and see what it sounds like?
Just askin’.

PS Old tube lover now running solid state. I never turn off anything in my system.

@nicktheknife 

i am surprised to hear of the unreliability of the rogue audio unit in your hands

was it an older or well used unit?  did you try to have them fix the problem?

i have had a eye on rogue, as a good, made in usa, brand of tube gear - the brand seems to have quite a few proponents on this and other forums, was perhaps going to try one sometime

now this gives me a little pause

I just bought a  Black Ice Fusion 3502 P Stereo Tube Power Amp (formerly Jolida) to replace my old Rogue Model 88 Magnum that took a dump for like the third time so I didn’t want to invest another dime in that amp.
The Black Ice may not be in the same class as the Linear Tube Audio but it sounds great to me. At least better than the Rogue.
The manual for the Black Ice states that they do not recommend leaving the amp on 24 hrs. a day as is the custom of some audiophiles to achieve max sonic performance on demand. While this is often recommended for solid-state equipment, Black Ice does not recommend this procedure for vacuum tube amps.
Now, there is a power switch on the back of the unit and one on the front panel. The one on the back is to be left on all the time. To operate the unit, press the switch located on the front panel to turn the power on. The indicator will flash red. Within a few seconds (seems longer) the tubes will begin to glow a soft orange color and the power switch will turn blue.
This was taken from the manual. I’m not exactly sure what is happening when the power switch is flashing ’red’ when first turned on but I assume that it’s some type of soft-start circuitry? I may be wrong as I don’t know enough about electrical engineering so I’m making an educated guess.
Anyhow, the manual clearly states not to leave it on all the time to preserve tube life.
Take that for what it’s worth but it seems like good sound advice coming directly from the manufacturer that I’m all too happy to follow.
If I plan to listen on and off during the day, I leave the amp on until I’m done for the day. It seems like it takes only about 5-10 minutes to warm up. But, I haven’t really evaluated the sound immediately after turning it on as I assume it’s not going to sound it’s best anyway so I usually give it 10 minutes before listening.

and as the dismal science, the ? is how many devils on the head of a pin.

I would cycle the preamp and amp off when not listening within the hour even as my Roger Modjeski designed RM-9 has a >10 k hour tube life.

well at least the EE are more likely to have taken and passed Engineering Economics....

@rtorchia Glad you found something you like better. If you like the sound and looks better, that's good enough reason to change. But if the only reason you got rid of your system was because it was hot and awkward, it's clear (a) you could have just turned your system off when not in use and (b) there are other more compact systems using tubes, including by Rogue, such as the Pharaoh. Just adding that for anyone who doesn't glean that your change was not forced by the options out there. There are options out there.

My wife left my Rogue tube amp and pre-amp system on all of the time and it was expensive both in tube replacement and utility expenses. The big amp was like a fireplace! I sold the whole system and replaced it with an Exogal digital power DAC combo and never looked back. The new components sound fantastic, take up very little space, and are cutting edge modern audio design. In my opinion the tube thing is greatly overrated and the tube sound is a likable form of distortion.

Kevin Deal is the founder/chief of Upscale Audio. Though I am not 100% sure on this, I'm pretty confident he's the guy behind the PrimaLuna brand.

@vinylfun

Sorry I dont know Kevin Deal. Is he an engineer ? What audio manufacturer  is he or / work for?

@hilde45 


Thats what I was thinking. How many electrical engineers with qualified expertise have actually weighed in here other than maybe atmas-sphere. 

This roundtable is entering the "How many angels can dance on the head of a pin" phase.

Two years ago I asked Kevin Deal, Upscale Audio at the RMAF show (Denver) should you leave an integrated amp on 24/7 or only when needed.  His expression and definitive answer was "Only on when you use it!"All my integrated amp's tubes still sound good today.  I just occasionally clean their pins.  :-)    

Tubes consume more power if turned on and off regularly so you should leave them on all the time? Clearly a flawed logic from the LTA owner 

BS, it absolutely does not cost you more energy to turn your tube amps on an off relative to leaving them on all the time. Tube life is shortened but not as dramatically as you would think. I do know some people who keep them on because they hate waiting for them to warm up. They are also filthy rich and could care less about tube life. Some tube units like my ARC phono amp have low power standby modes. I do leave that on continuously. I have a class AB SS amp in the workshop that I leave on all the time but the JC 1's in the main system are turned off.
Turning the tubes on and off stresses the filament due to expansion and contraction of the metal with the extreme changes in temperature. Same for transistors although the temperature changes are not as extreme. 

@1extreme 

@larryi 

Thx, super helpful explanation and information. A very knowledgeable forum. 

Nobody leaves tube amps on all the time turn on 1 hour before listing is enough.

aj,

Whether turning a tube on & off or leaving it on, a tube doesn’t consume any more power than they are designed to consume (as long as your amp is functioning properly and biased correctly). But the initial temp change from cold to hot when powering on is what is especially stressful on tubes especially power tubes.

Your LTA amp is designed to be less stressful on tubes thus longer life so I wouldn’t be as concerned with your amps. I would treat it like a preamp. Turn it off when you leave the house or go to sleep. Other times use discretion.

PS. EDIT: What Larryi2 said above while I was typing.

Tubes do not "use" more energy at turn on or turn off.  That is NOT the basis for concern with turn on causing more damage to a tube than leaving it on constantly.  The concern has to do with two different issues.  The first is the stress from thermal shock.  When a cold tube is suddenly heated, the elements that are heated are stressed by the sudden heating and expansion.  That is why light bulb most often fail at the moment the light is switched on.  Tubes are subject to some thermal stress, but, it is not nearly as severe as with a light bulb.  Tubes are not made to heat up and start working as fast as a light bulb has to heat up and emit light. 

The second issue is what is sometimes referred to as cathode stripping.  If high voltage is suddenly applied to the anode before the cathode/heater has warmed up enough to be emitting electrons, the pull of the anode trying to attract those electrons can damage the cathode.

In a properly designed amp, the current should be applied slowly enough, and ideally, first to the cathode/heater circuit, and ramped up to avoid either concern.   Some tube units have such "soft start" circuits and utilize a relay that delays full power to the anode side of the tube.  My headphone amp has a circuit that takes a full minute before warm up is complete and the amp is operational.

Leave NOS on 24/7? Nah. Heck no. It’s not about money. It’s about scarcity.

If you are listening for an extended period of time, e.g. all day, then yes. Power up in in the morning, then power down at the end of the day or weekend.

NOS are expensive and more importantly--scarce. If you decide to leave on for 24/7, then roll out the rare valves/tubes.

I have two separate systems, and they are in different rooms. One is valve/tubed and the other is sand/solid state. I save the better (valve/tube) system for extended listening. The cheaper sand system monoblocks running the high-end Martin Logans I use and abuse almost daily, because I don’t care about their longevity.

ML informed me that the polymer nylon diaphragm has a very limited lifespan of only 15 years. So, I don’t and can’t care that much. I can "care-less" :)

best.
g

@1extreme

Hi thx for the reply. Do you have an inconsistency in your first paragraph? In the first instance you said tubes don’t consume excess power when turned on, then you follow up with the constant turning on/off shortens tube life. Arent those two statements binary? Anyway, what you said is exactly what the engineer who built the amps said-- "frequent on /off tends to reduce tube life so leave them on"! That has the added benefit of keeping them warmed up all the time.

aj,

The arguement for leaving tubes on is that they sound better fully warmed up not that the tubes consume excess power when you turn them on. Frequent on off tends to reduce tube life especially power output tubes. 

You should perform some experiments by listening to your LTA amp from a cold start vs fully warmed up. Can you hear a difference? What is the minimal acceptable warm up time? Please report back what you find.

I have a pair of Futterman OTL3s, modified from pentode to triode. 

If I’m listening and have to walk away for up to an hour or two, I leave them running. 

Otherwise, I turn them on, wait a half hour, and when I’m done, they go off. 

Reasons:
- fire hazard
- tube wear
- waste of electricity

Being an owner of ARC tube gear, my response is NO!  My gear is probably 80% of the way there after 20 to 30 minutes after start-up.  After an hour, my gear is all the way there.

I echo what another some of the posters said about tube life.  My amp uses KT-150s, which are expensive power tubes that, per ARC, have a service life of 3000 hours.  Too darn expensive to leave my gear running 24/7. 

I am also concerned about energy costs and even safety.

So, ... NO!!!    

I dont need any more convincing. Mr. Berning’s ZOTL preamp/amp technology is mind blowing performance, like nothing I’ve ever experienced sonically and I don’t want that burn out faster lol.

His reasoning was that it uses considerable more energy to turn on/off on a regular basis.

Do others agree?

Uh, no. Not even other manufacturers. He should have done his math before saying something like that.


Now the amps probably take about an hour or two to sound their best; if this is the criteria (other than just simple warmup which takes 30 seconds) then the answer is still 'no'.

Today I will be watching football with the volume off,and listening to my main system which has a tube preamp. I won’t be leaving the house,so I will keep it powered up even if I go hang with the Mrs. before kick off. 

@avanti1960


That’s the conundrum. The NOS Mullard Tubes, all 8 of them in my 2 amps ( a quad per) are EF2 from the early 1960s, are almost impossible to find outside of LTA and prices are over $200 per tube if you do.  Even LTA acknowledges that unless they find another warehouse in Eastern Asia with 60 year old unopened boxes they will one day soon need to find a replacement tube for their zotl40 reference amp so I may not want to test Mark’s suggestion.

It is an irresponsible idea to needlessly consume power.

"Tubes, generally speaking, are NOT like light bulbs, so they do not suffer nearly as much from the thermal shock of being turned on."      Actually; the cathode in a vacuum tube is heated by a refractory metal filament, generally tungsten, very much like a lightbulb’s.      Some cathodes (directly heated) are the filament. https://en.wikipedia.org/wiki/Hot_cathode      Even so; as much as I’ve spent on my NOS valves, persuading me to leave them on, 24/7, would be a difficult task.     Glad my Cary monoblocks have separate B+ switches, so I can give the electrons time to start their hot little dance.

On the LTA website it mentions that they drive the tubes with 1/3 of the amount of current that typical tube amps use which is part of the recommendation.
Also many believe that tube life is shortened because of multiple power up / power down cycles. Consider the physics of a cycle- abrupt current and heat to a cold tube and tube glass, thermal expansion differences between materials- e.g. glass and different metals and pins that are expected to hold a mechanical vacuum to survive.  Running at temperature and maximum thermally expanded state for many hours then a rapid cool down / thermal shrink after power down.  This happens every power up / run/ and power down.  Thermally and mechanically stressful to the tube elements and glass.  

Most tubes do seem to fail at startup as opposed to failing gracefully while running- similar to an incandescent light bulb.

I would consider leaving them on with an LTA product and see how it goes.

I don't own LTA, so maybe that is a very special case. Can't speak to it.
In addition to fire hazard, tube life (both good points), my gear consumes over 100w when idle. I listen probably 2 hours a day, maximum, on average. This probably doesn't mean much, given the other factors, but at my electricity rates, the difference in energy use is $105 vs. $9. For decent tubes, that's the cost of about 2 tubes per year in energy savings. Over a few years, it would add up.

I thought that David Berning was the sole designer of the LTA gear.  

I still turn them off even if I know that I am going to listen later

No matter the built-in protection, I take the point about gas filled tubes and fires and its enough convincing for me to shut it down every night or when we leave the house. Thanks for that gloriousunicorns :)

I guess it just comes down to some daily thought around when you may use your system throughout a normal 10 hour period in that day and plan accordingly 👌 So one follow up may be if I use my system on the weekends in the afternoon, take a few hours break and then again at night --- what say yee - on or off?

As a side matter, I have left my solid state amps always on 24/7 in my home theater room since 2011. And that was on the advice at the time of just about everyone on the theory that they draw very little power when idle and not being used and there is a bigger risk with the amp breaking down with constant switching on and off.

@tomic601
Wasn’t Einstein a physicist? They know a thing or two about energy and glass tubes. ;)

I own 2 LTA amps now and I’ve also owned the LTA Ultralinear. These amps do run the tubes significantly cooler and stress them less than other amps using the same tubes. I’ve also talked to Mark several times at audio shows and he really seems to know his stuff. 

I can see why he would recommend leaving them on because every time a tube amp turns on and off, that’s wear and tear on the tube. Even if it has soft start circuitry. An example, I have an older Modwright pre amp and the on/off toggle switch was damaged in shipping. I didn’t know that and when I started using it, the on/off switch made intermittent contact and rapidly shut the pre on and off a bunch of times. That quick series of powering up and down was enough to kill the rectifier tube and also F’ed up the driver tubes. Quickly turning tube amps on and off is really hard on the tubes. 

That said, I wouldn’t leave the LTA amps on all the time either. If I’m just going out for an hour or so and I plan on listening when I come back, I’ll leave it on. But I wouldn’t leave them on for long periods if I’m not around. Too paranoid for that. They have built in protection circuits but my thought is, why risk it? I’d rather not have a fire happen that I could’ve prevented. Imagine trying to explain to the authorities what happened. “Yeah, I leave my tube amps running all the time... Oh, you don’t know what tubes are? They’re gas filled bottles that run hot and at high voltages.” 

Leaving a tube amp on 24/7 implies that it will be left on unattended. If one of the tubes fails and the amp is unattended this could cause a significant fire hazard IMO. I would NEVER leave my tube amps or preamp on 24/7 under any circumstances.

The way I read it is his reasoning is based on environmental concerns and not the life of the tubes. I have had a Cat preamp for over 25 years and there is no difference in sound after 20 minutes of playing no matter how long it is left on. Based on that, I see no reason to leave them on for a minute more than when you are done listening for the day.

no - what a stupid idea

but this is a super good thread.....

there is a class most Physicist skip...Engineering Economics.....

Berning is a physicist.  I'll try to fnd out the science. 

There are ways to gently turn on tube gear, such as a soft-start circuit, relays that apply full power to the B+ rail after the heater/cathode has been warmed up and emitting, etc.  If a particular design is hard on startup, it really should be the designer's responsibility to use such measures instead of recommending that the owner waste electricity, prematurely burn up tubes, or increase the risk of damage to equipment and the home if something goes wrong with an unattended piece of gear.  

Tubes, generally speaking, are NOT like light bulbs, so they do not suffer nearly as much from the thermal shock of being turned on.  While tube gear might take a few minutes to sound its best after being turned on, that time is typically shorter than the warm-up time for solid state.  It really shouldn't be the case that it is better to leave the gear on all the time.

I just can't get myself to leave my tubed integrated on all the time, even though a tech suggested I do it.  It just doesn't sit right for this virtuous, right-thinking guy.  To be honest, if it does indeed shorten tube life, so be it.  It'll give me an opportunity to try out a different brand or model of tubes.

@audition_audio

Yes I thought I made that clear. Thats the suggestion from the designers themselves given the power surge in turning on and off multiple times. My healthy skepticism is questioning that. 

I use a tube preamp in my main system,and I don’t feel comfortable leaving it on if I have to run to the store. I’m a no vote on that one.

If you really want to know how to treat Berning designed gear you should talk to the man himself. Turn off when not in use I say.

This is exactly why I'm seeking other input. Thank you.