Amplifier warm up

The Pass XA25 uses 240 watts at on/standby.  I can't see $20-35 a month in extra power usage.  I usually turn it on ahead of time and it does sound better after warm up.  Some components need to get to 50C to sound right.

I've definitely noticed that SS sounds better when left on all the time.  I only have a class a/b integrated and phono stage that I leave on, so it's not using much power when not in use.  Recently, I went out of town for a few days, so I powered everything down.  When I returned, I was looking forward to hearing my rig.  Those first few albums were pretty painful - everything sounded thin and glassy.  The next night, things were sounding great again.  I really wasn't expecting such a difference, but it wasn't subtle.  That being said, if I had a class A amp, I wouldn't leave it due to environmental concerns.  

@vegasears 

have not heard of cool down concept for amps

not sure it matters, but pretty sure it doesn't hurt

I use tubes amps.  I warm them up no less than 15 minutes before use.  I also let the amps cool down for the same amount of time before powering down.  I started doing the warm up cool down many years ago and it increased my tube life nicely.

I have a new warm-up ritual now thanks to this thread. Before this I would turn on the amp, motor controller, and phono stage, all at least a half an hour before listening. Now I also let the motor/platter run almost as long. 

This has really made a difference in the quality of those first few minutes. There's still improvement across the first side, but its starting from a much higher level. 

Okay, don't want to exaggerate this too much. Its not like this is something everyone will even be able to notice. Obviously if we learn anything from threads like this its that there's all different levels of listeners. Some never will hear any difference. But for those who do, this is definitely worth doing.

It was the sulforaphane in the broccoli.

Two thoughts... you might be drinking the wrong wimpy Syrah... our house Syrah is DAVIS Family from Healdsburg. For a real Petite with correct spelling and California fruit, I can highly highly recommend a truckload batch from Romeo in Sequim WA from Lost Mountain Winery - it has cellared extremely well. Thanks for the correction 

@tomic601
@twoleftears

twoleft is correct - from dr vinny @ wine spectator:

"Petite Sirah (you’ve clearly seen some of the wineries that use the alternative spelling of "Petite Syrah") and Syrah are two different red grapes. Syrah (also known as Shiraz in Australia and South Africa) hails from France’s Rhône Valley, where it’s the primary component of some of the world’s most revered red wines from Hermitage and Côte-Rôtie.

Meanwhile, Petite Sirah is the American name for the Durif grape, another French import, which is a cross between the Syrah and Peloursin grapes. Durif never took off in France, but it did in California.

Even though its name implies it may be a lighter version of Syrah, this is definitely not the case. Petites are anything but Petite. I’ve heard that Petite Sirah got its name because the grape bunch looked like a bunch of Syrah grapes, but with smaller berries. These smaller berries mean there’s a higher skin-to-pulp ratio in the grapes, the resulting wines are inky dark and bold, with rich flavors and powerfully dense tannins. Petites are much more tannic and rustic than Syrahs—I often get wild blackberry and huckleberry pie flavors."

Isn't that Petit Sirah?  DNA analysis shows it actually bears no relation to Syrah.  And so it goes.

Thanks for that information @slaw. Steve hadn't told me that but he put two big low noise Plitrons in my SMc Audio DNA-1 UltraG-20 monoblocks earlier this year.  That may be why he offered the option of having no on/off switch.

Steve McCormick says the Plitron transformers need 24' hours to reach optimum operating temp. I always turn my amp on the day before listening.

Yes, that's why I don't listen to solid state anymore!😁

Had me at Petit Syrah....

Another theory is that side B is a super white hot stamper !!!! You are halfway to rich !!!!!

I leave my Pass Labs XA-60.5s in standby at all times, except storms and extended leaves.
They still take 20-30 minutes to sound their best (or maybe it’s the tube preamp).

mitch2, thank you for your comments.

I have not used a cable cooker; there are simply too many things to do in audio that I have determined are of more significance to me. You can bet the first thing I would do if I got my hands on a cable cooker is repeat my experiment with sets of new cables to get to the bottom line regarding cable cookers.

If any cable cooker manufacturer wants me to assess, I can. But, I will vet the product first, as I will not spend extended time on a product that I deem of marginal value. If anyone wishes to extend that courtesy to me, they should expect that I will conduct a similar comparison as I did in the Audiophile Law article. That would be as fair an assessment as the come. :)

One last comment to perhaps head off objections. Someone might say that I'm predisposed to not hearing the benefit, as though my bias would not allow me to accept or acknowledge the putative benefit. Let's be more mature than that. I compare settings, cable sets, my Schroeder Method of IC Placement, etc. on a weekly basis, so if any change is to be deemed significant it has to pass my Law of Efficacy, which states that it must be instantly/immediatley heard, repeatable (i.e. In this case, heard concisely, even if cables are moved around), and subjectively benefit holistically, not just partially).

@douglas_schroeder  - I read the article and am not surprised with the results.  Since I don't view these things as a contest, I am not concerned that some here believe in significant changes due to burn-in, but I don't.  I think you are getting close to what happens with your statement:

I would assert that a significant change happens to the hearer during the honeymoon period as the ears acclimate to the product. Why is there so little discussion of “Acclimatization”?

Could this be a reason some manufacturers recommend an extended burn-in period before making a decision about the sound quality of new equipment?  Considering some combination of The Endowment Effect, the Sunk Cost Fallacy, or some other psychological phenomenon, some manufacturers (or their marketing departments) probably realized the longer a person owns something, the less likely they are to return it.

While I don't believe in extended burn-in, I have heard the difference between an amplifier that is warmed up vs. one turned on from a cold start.  The difference was apparent with my former amplifiers - Class A Clayton M300s.  They were most of the way there after about 30 minutes and seemed fully on task after an hour.

As a follow-up to your burn-in article, I would be interested in hearing about whether you and David could hear differences between brand new cables and cables that have been conditioned on something like the Cable Cooker.
 

Once again,  for the community's benefit,  read my article at Dagogo.com; 
"Audiophile Law: Thou Shalt Not Overemphasize Burn In", wherein I put both burn/break in and warm up to the test. 

I am uninterested in semantics arguments,  or debate with people lacking experience of actual comparisons of systems side by side.  :)

I'm a bit skeptical of manufactures who say that their products need hundreds of hours of break in before performing or sounding good. Although some products do benefit from a break in period (several hours, not hundreds of hours) It has been my experience that good products will sound good and perform well out of the box (so too speak) after being allowed to warm up. I do know that some amps, pre amps DACs and CDPs (old or new and some more than others) will improve in sound after being allowed to warm up before giving a serious listen.

My, tubed pre amp sounds better after about 20 minuets of warm up, but I can't hear much, if any difference, after that. It just sounds really good. I shut it off when I am through listening, to save on my tubes and power bill, if I'm not going to be using it again for several more hours.

My Integrated tube amp sounds best after about 1/2 hour of warm up and I can't hear any difference after that. I also shut it off when I'm not going to be using it for several hours.

My old ADCOM SS power amp sounds best after at least 8 or 10 hours of warm up. When I'm using it in my main system, I leave it on continually. For those with these older ADCOMs, if you're not giving them at least 8 or 10 hours or warm up, you are missing out on how truly good they can sound. Many other SS amps, likewise, sound their best after several hours of warm up....Jim

My JC1’s live in standby, and they start to sound their best about 1 hour into a listening session starting at 5:30 on a Friday evening.   A Sunday morning with JS Bach is sublime at about 6am, with about a ½ hour of playing time. I suspect it’s a combination of time of day/power grid activity and transistor temperature stabilization.  Most natural phenomena have several factors operating simultaneously.  Science is so... complicated. 

@millercarbon There's no such thing as warm-up, and certainly nothing needs to be left on all the time.

This is from his lengthy post on the other thread on this subject, just this week  Which is it Chucky?
Of course it takes time to reach thermal equilibrium. A shorter time for tubes than transistors.

+2 atmasphere.  Are not most components within an amplifier designed to be at spec once they reach thermal equilibrium? 

I have had many tube preamps and amps. And for each of them, the sound is MUCH better after 1h or more of warming up. The sound is better also later in the afternoon even if my system is in a separate dedicated power line. My main system is Allnic preamp with Shindo monos.

The phenomenon is not necessarily universal. Just sayin

I have an F5 (Class A)that sounds great cold and deteriorates slightly as the temp goes up in my room, say 2 hrs later.

Probably has to do with improper bias calibration during the build finish.

Just to add another eccentricity to the forum cool aid, I like my speakers ** toed out ** (again in my particular situation). :-)

atmasphere = +1 (and; more = better)

There’s a reason why most SS amps have the on/off switch hidden inconveniently on the back - they expect you to leave the gear running. As one commenter noted, though, yes, the components do deteriorate over time (I just replaced a Conrad Johnson amp that had run almost continuously for 12 years; over the last year I had noted that the bass response was degrading). Counterpoint is that the majority of electronics failures occur during power up. Pick your poison?

My sugden class A takes a good 90 minutes to sound its best, not that it sounds like crap prior....it also makes for a great space heater in winter.

Actually, i agree with both the OP and N80.
Yes! solid state warms up, and over a 30-60 minute period the majority occurs. Many solid (state) reasons.
That said, everything sounds better after a glass of wine, or with stable blood sugar or whatever. So joking or not, N80 is, IMO, absolutely right. Since i design commercially, i have to account for the many things that might fool me into thinking something is better or worse. And how i feel is culprit #1.  That's why subjective evaluations are so difficult, and generally viewed as without credibility. Yet i wont argue that we need listening - i cannot measure most differences that i can reliably hear.
G

Really? I'm the only one who thinks, seriously, that having dinner is going to change one's perceptions just as truly as an amplifier's warm-up?  (I know if I'm waiting to eat, I respond to music a lot less happily than after a nice dinner.)

It's like being at a strip club in an anti-universe: LEAVE IT ON!

@aewarren

There are a few other possibilities that were not considered:

1. Side One of the LP may be your favorite and thus it may have gotten more play and is showing its age compared to Side 2 that is more pristine.
2. By the time you had finished your meal, the power grid in your area may have become less busy and therefore better suited to your listening session.
3. That bong hit.

4.  That ribeye steak in your tummy makes you sleepy
5.  Those three glasses of petit syrah makes you loopy
6.  That square of tiramisu pushed you over the edge

lololololololololol  ..........

atmasphere8,812 posts10-27-2020 3:47pmYou can't take any good system seriously for the first 1/2 hour or so!

Indeed - also your phonostage and cartridge need warming up. With vinyl things can be very frustrating. Part of that early dissatisfaction will be augmented by the phonostage and cartridge not performing yet.

There are a few other possibilities that were not considered:

1. Side One of the LP may be your favorite and thus it may have gotten more play and is showing its age compared to Side 2 that is more pristine.
2. By the time you had finished your meal, the power grid in your area may have become less busy and therefore better suited to your listening session.
3. That bong hit.

I leave mine on 24/7 unless there is a serious threat like a storm.

Unless your amps are choked for air in a cabinet I've never been a fan lol .class A gets so hot its hard to even touch and I would leave on 24/7 . My hybrid tubes get hot!
imho

Yes.

Temperature changes will change the biases in transistors and hence make differences.

It is almost like an ICE engine.  It runs better when it is warm.

ricevs
I am totally off grid(closest power pole is 2miles away) ,I have solar ,generator backup and lithium4 batteries . I do power my hybrid down and it takes a solid hour min, to get my system to open up. I run class D in my video room that is always in standby mode .

So if I’m using little fans to manage the temperature of my SS amp, does that mean it’s not warming up sufficiently to play at its fullest potential?

@aeschwartz

It appears your A21+ amp is consuming 1-watt on StandBy mode, and its very possible you’ll hear a difference after 2+hrs of warmup-play, sure. I tested a smaller A23+ a few months back and it sounded better after 1-2hrs.

Most good ClassA solid state amps I’ve owned sounded pretty bad at 15-30 minutes from cold startup, and once the large transformers became warm and fully saturated, I could always hear notable changes at 1hr and 4+hrs. Some other well known Class-A amps notably improve after 8-24hrs warmup once everything becomes nice and toasty. I’m not sure I’d leave an ultra high-end Class-A SS amp on other than for weekends or long listening days.

With my current tube mono amps, 1hr of warmup is all that’s needed and the sound really does not change after 1hr. Varies some by amp type and design of course, type of transformers used, YMMV.

Cold vs hot makes no difference to my ears. But that's just my ears. They're not the finely tuned instruments possessed by true audiophiles.


My SS amp manual (Madrigal Proceed HPA 2) says to leave it on. I can't bring myself to do it. I'm hardly what anyone would call an environmentalist....more like a conservationist....but the bottom line is that even in standby mode that amp makes heat. A fair amount of it too. I have no idea what that translates into in terms of electricity usage but it cannot be negligible. And my music rooms tends to be a tad hot in the summer and a tad cool in the winter compared to the rest of the house. That last thing I want in a Carolina summer is more heat. So maybe I should leave it on in the winter.

I believe my AR LS16 tube pre-amp manual says to leave it on as well, in standby mode, but I do not remember and can't recall if it makes heat in standby mode. I would hope not.

Guys,
You need to get off the grid....check this out....better than $10K PS Audio:

http://enjoythemusic.com/magazine/equipment/0119/Goal_Zero_Yeti_400_Lithium_Portable_Power_Station_R...

You really don't need a Goal Zero with its fan noise.  You can buy low distortion sine wave inverters for a few hundred $ and a 100 amp hour battery or two and a big charger and run your system all day before needing to charge.  You can listen while charging but it won't sound as good.

As good as inverters are (completely off the grid and better sound than practically any line condiioner) they still make noise.  My friend is using the Puritan line filter after his 3000 watt inverter and it sounds even better and it isolates each component from each other.  Incredible sound....same sound day and night.

It's certainly been my experience that noisy AC lines are a culprit for variability in sonics along with warm up time.  With all my gear over the years 1 hr seems to do it for warm up benefits...more just doesn't help much for my ears.  But the time of day has huge sonic swings and compelled me to eventually get a PS Audio Power Regenerator.  It even measures the distortion coming into the unit and I can see it go from more than 4% THD during peak area usage periods down to 2% late at night or very early in the morning.  With the regenerator the output is consistently below 0.1% THD which has seriously enhanced my listening experience.  Plus it regulates the voltage to a consistent 120V....otherwise mine fluctuates 118-123V otherwise throughout the day.

Boz Scaggs always sounds better on a full stomach. My s.s. Ayre amps have a standby mode in which they are always on but not fully powered until ready to use. They fully warm up (to my ears) in about 15 minutes.

Like johnto said, why didn't you just play side A again to compare?

My new SMc Audio monoblocks do not have a power switch, just power cords to the wall.  Steve McCormack recommends leaving them turned on for best sound and turning them off for:

• storms and potential power outages
• vacations
• other periods when I do not plan to listen for extended periods of time

Not every amp is going to behave the same and maybe not every amp is thermally suited to remain on all the time....like my former 300wpc Class A Claytons.  I have heard the on/off cycling can be harder on the circuitry than leaving them powered up but.....who knows?

+1 millercarbon's point about AC noise. OP, if you really want to do a comparison, make sure you do it during the same period -- all during the day vs. all during the evening. If you're comparing evening to daytime, then you're not eliminating the "noise on the line" factor (which may or may not be a factor where you live, but you'd eliminate it by simply controlling the day/time.

Many moons ago I bought a Classe solid state preamp.  I was surprised that it had no on and off switch!  I presumed that solid state is better if it is left on all the time!

A lot of the class D (non pro stuff), says "Leave it on". In the summer anything with valves gets turned off.. 15-30 min in the summer time for a tube preamp to warm up.. An hour in the winter though.. I like 60 degrees in the winter, with valve amps and valve preamps.. It takes about 30 min, if I played them the day before..(winter). The speakers sound better on cool crisp days, too. 

Regards

The legendary Ed Meitner at EMM Labs strongly recommends to never turn their gear off. I leave my DV2 and Pre on 24/7. 

Yup. Not surprised. Not the least bit.

This all seemed preposterous when I first heard about it back in the 90's. But, as usual, if it can be tested super easy then why waste time arguing?
Find out for yoursel! So I left my 1970's era Kenwood amp on 24/7. Days then weeks went by with no perceptible change in sound. Like I thought, BS. Oh well. Been on a week, might as well just leave it on.
Until one day for some reason it gets turned off. Oh well who cares it doesn't make any difference anyway. Next day turn it on to listen and what the... sounds like crap!  

This was my first time learning that sometimes when differences are small and you're not used to hearing them, can't recognize them, it helps to listen long enough to get accustomed to the new sound. Because then when it changes you will notice. Looking back its clear the amp was improving the whole time it was on, just at a very slow gradual rate that made it hard to notice until quite some time had gone by.

Its like this with a lot of things. AC power improves very gradually through the evening and late into the night. Even when things are left on still the whole system gradually improves when playing music. Differences that are hard to hear when you're unfamiliar and listening to 30 year old Kenwood and JBL are indescribably wonderful late at night with a really good system.

Anyone serious about building a really good system, you could do worse than to learn to hear these little changes.

When I had my Odyssey Stratos Extreme amp, I left it on for 5 years straight as that was how it was designed and it always sounded great.  After 5 years, my wife and I went on a 3 week vacation, so I shut down the amp.  Upon return, it took a week for the system to sound good again.