Four Hour Tube Amp Warm-Up

Will try that. Thanks

My experience is as a result of having a Vinyl / CD Source, along with ESL Speakers and Cabinet Speakers, is that with CD used as the first medium and an ESL, the Sweet Spot is usually quite present before an Album Side is over.

With Vinyl as the first medium and an ESL, the sweet spot is quite present on the second side of an Album and will be max'ed not too long after. I put some of this down to the Cart' findings it optimised condition as well.

Using Cabinet Speakers the Sweet Spot will appear at almost the same time line for both Vinyl/CD. The sweet spot can start to be noticed after a few hours. I put this down to the Drivers Suspension becoming optimised. When using the Cabinet Speakers I have conditioned myself to use CD as the first music as a Background music, prior to sitting in front of the system.

With the price of Vintage Valves, it is not a nice experience to have them wasted in use for Warming up other devices as well, to get them to an optimised function.

A 'cheapo' integrated amp' to drive the Cabinet Speakers for a period of time would be the most cost effective, preserving Valves for best SQ replays. 

@bolong I have to agree. 20 mins gets them up and running (same time needed to "warm up" my turntable bearing) but they do open up as the hours go by. By the time I’m turning the things off after 4+ hours, they’re at their sweetest and most three dimensional. This seems to hold at any time of the day too, so I don't think it's related to cleaner power as the day winds down. 

Never experienced anything like that with pure tube amps. In fact I always find them quick to warm up. I once had a hybrid electrostatic headphone amp (grounded grid EL34 with solid state CCS outputs) that took like an hour to sound its best -- but I'm pretty sure that was from the transistors. 

Time has passed and the Sophia Electric EL34's are probably technically burned in now. I would say that about an hour and half use/warmup blooms them nicely. However, a couple of weeks ago I accidentally left the tube amps on for 7 hours unattended. When I got home that night and started playing I was taken back to the real, real "bloom." What can I say - there is this everyday operating dimension and then there is the dimension slightly beyond. I am hopeful that electrical theory will one day catch up.

After making some adjustments it is down to about a 2 hour warm up now.

bolong +1; a weak tube can take a long time to warm up properly

Where is @tubebuffer these days?
As Confucius say, “Man with strong tube, need little time to warm up.”

@bolong +1; a weak tube can take a long time to warm up properly.

Same here... With the little soundartist el-34, 4hrs is needed to sound best.

Since I initiated this thread things have changed for the better. Now my set up is sounding very acceptable after an hour warm up. Tweaking has helped.

All the power cables are Anticables, and they are all plugged directly into the wall now except for the cables to the Jay's Audio redbook transport and the Denafrips Terminator DAC  - those cables are still plugged into the Shunyata power conditioner. Running the Terminator in oversampling mode is now better.

Speaker cable is now vintage cloth covered Western Electric tinned multi-stranded 10 gauge wire which is complementing the Primaluna's and the Cornwall 4's with no loss of detail and good PRAT. The bi-wire jumpers are vintage 16 gauge Western Electric pink cloth wire which seems to slightly tame the treble. I tried it with 10 gauge WE jumpers, but the treble ran a bit hot that way. This may or may not be logical from an electrical engineering standpoint since the bi-wire terminals all theoretically end up in the same places internally but..whatever.

I have also been re-burning CD's from .flac to .wav (in JRiver) and think they sound better perhaps because of less computing in the signal chain and therefore slightly less noise.

Also discovered a 12au7 tube that was microphonic. Replaced it and now the background is much blacker. Also reinserted some vintage 12au7 Amperex "Bugle Boys" into the signal positions, and this has helped quite a bit. The Primaluna's do not like "alien" 12au7's, but just the Bugle Boys as signal tubes are doing fine.

Also, built some floor attached angling guides for the speakers so that they can be pivoted predictably and in perfect unison relative to each other and the back wall, and the distances between them can be exactly gauged relative to my listening chair. This has improved sound-staging quite a lot.

Tweak City over and out.

Just wondering if this holds with the experience of other tube ampers.

@bolong No. It takes our amps about an hour. About 25 years ago our amps took about 3 hours but component improvements have changed that.

1/2 hour to an hour should do it

My experience with warm up time has been so variable over thirty years, variability in comments not surprising to me. I've found system presentation or voicing, tube types and qualities, especially power tubes in amps, standby ability, number of tubes in entire system, AC quality, cabling, on and on ad nauseam, all have bearing of when system kicks in, even mood plays role. I just wonder if there is some point of stabilization applicable to every single little thing in our systems, and ourselves for that matter?

With -20 degree wind chill factors during recent listening session even thought about how temp could be affecting AC cabling exposed to these temps, specifically, could temp of wire affect sound quality? Obviously heat is of concern here, does more heat mean quicker warm up times, cold or cooler longer times? This meant in relation to all parts within components.

I only know every listening session has a point where things just kick in, assuming nothing breaking in. I only find consistency when my system is in static mode, meaning nothing changed over certain length of time.

I am really sorry to hear your system requires such an extended warmup. For tube equipment this is simply rediculous. I have owned a PrimaLuna integrated amp for over 10 years in my home office.

Ditto

I may have never discovered it’s sweet spot.

When did we switch from amps to women?

All tube amplifiers sound OK after 30 minutes. But if you listen carefully sound is getting better during 2-3 hours. Especially it is true for not feedback circuits. I also paid attention that this difference gets bigger after I tweaked and improved sound quality my 300B amplifier. I had McIntosh MC30 and Marantz 8b amplifiers. All of them benefited from couple of hour warm up.
Another fact, in recording studios all used tube equipment is switched on in start of the day and switched off in the end of the working day.

I am really sorry to hear your system requires such an extended warmup. For tube equipment this is simply rediculous. I have owned a PrimaLuna integrated amp for over 10 years in my home office. I may have never discovered it’s sweet spot. I seldom have spent more that two or three hours in my office.

My main system is contemporary Audio Research Reference gear and my headphone system is Woo 300b… and neither have much of a warm up gain. In the past the Reference 5 series premps had a strange ~ 12 minute requirement to have signal passing through it until reaching optimal sound quality… it could be on for hours… but still had to have a signal going through it. This went away with the 6 series preamps. I don’t hear a noticeable improvement after the first couple minutes.

In decades prior, my equipment had a noticable improvement after 15 minutes or twenty… nothing like four hours.

My 300B SET amplifier also sounds it best after 3-4 warm-up hours. After 1.5-2 hours it sounds not bad but not as magical smooth and clear as after 3-4 hours. 

When I had transistor amplifier Plinius 8200 integrated it was always on. Without couple of days warm-up the sound was hard to listen to.

It’s difficult to really know for sure because I’ve not listened to the same music at 30 minutes, 1 hour, 2 hours etc. It’s also difficult to remember & accurately compare w/ that time lapse in between. I don’t think our sonic memory is that good over time, even relatively short amounts. 
 

“Warm up” time could also be be within in our brains & it takes me time to relax, unwind & really get into the music & really enjoy it.

That all said, I have noticed w my Rogers EFH 200 Mark II ( 2- KT 150’s per side & a seriously large power transformer) that the sound definitely sounds more full body & fleshed out after about 1 hour. Beyond that , I can’t say much. 

@bigtwin I cannot think of a single Tube Amplifier manufacturer that would say leave it powered on. Nor a Hybrid tube SS manufacturer.  

@jerryg123 Thanks.  I stand corrected.  My manufacturers, Hegel, Esoteric, Triode Audio Japan, PrimaLuna, all recomend turning equipment off when not in use.  Oh well, whatever works for you is all that counts.  Merry Christmas.  

@bigtwin Heed Audio, Simaudio, Pass Labs, SPL, AVA, just to name a few. 

bigtwin wrote: "I'm not aware any any manufacturer that suggests leaving equipment powered up 24/7?  I would think you are only shortening the eventual life span of things doing this?  Just asking."

From the Pass XA25 owner manual...

Leave it on or turn it off: The product is designed to be left on all the time. The exception to this might be a case where the unit will not be used for an extended time - in that case it can be turn off. The main power switch is located next to the AC power cord. (THIS REFERS TO THE REAR MAIN POWER SWITCH)

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

You are now ready to play music. Turn the level at the source or preamp to a low level. Press the power switch on the front panel of the XA25, the blue LED above the power switch will light. Turn the volume up to your preferred listening level. Sit back and enjoy! The XA25 takes approximately an hour to fully warm up and sounds better as it does. Pushing the power button on the front panel of the XA25 a second time turns it off and extinguishes the blue LED. (THIS REFERS TO THE FRONT PANEL POWER ON PUSH BUTTON)

bigtwin wrote: "I'm not aware any any manufacturer that suggests leaving equipment powered up 24/7?  I would think you are only shortening the eventual life span of things doing this?  Just asking."

When I bought my Pass Labs XP17 phonostage I called Pass and asked if it would be OK to leave it on 24/7.  I was told that it was designed to be left on all the time and that is why the only off/on switch is located on the back of the component. 

@mulveling "However, it is very difficult to separate any such sonic differences from psychoacoustic explanations"

This is the Achilles' heel for many discussions. Obviously, the OP knows his own mind best, and we have to stipulate to what he's hearing. That said, 4 hours is a very long time, certainly an outlier in terms of what others report and what the equipment should be able to do. (Imagine a car that took a full 60 seconds to reach 60 mph --- that would obviously indicate a problem or bad design.)

As for your comment about the fallibility of SS -- good point. Tangentially, I'll confess that my Pass XA25 takes about as long as my KT88 tube amp to sound decent, and it sounds great after it's been on a long, long time. 

I'll try to be more precise in my warm up time for this post. Much of the warm up time has to do with amp, tube and parts replacement. New tube components, or new tubes or parts in well burned in tube equipment never bloom in initial phases or hours of burn in. Over time, at somewhere between 50 and 100 hours blooming will often take more warm up time, this may be as much as 4 hours, as burn in progresses warm up time decreases until a consistent warm up time of aprox 1 hour at full burn in.

My 300b monoblocks are undergoing this  repeated progression at this very moment, recently replaced all coupling caps with Duelund Cast, getting up into 60 hour range and blooming is coming in starting around 3 hours and progressing from there. Between changing out tube components, parts and tubes for nearly thirty years now this is entirely common occurrence.

I’m becoming more open to the idea that sound quality could improve up to 4 hours, which seems to be around the amount of time for the big transformers & their potting to fully warm up. However, it is very difficult to separate any such sonic differences from psychoacoustic explanations (without 2 of the same amp), and I still posit that if an doesn’t sound good within 10 minutes of power up, something might be wrong or "off" with it.

4 hours -- wow. So, tube life is, in effect, one quarter of their expected life for good listening? That will sound like an argument for solid state to many.

@hilde45  As per above, I would never wait 4 hours to start enjoying the amp. And as for solid-state, there’s another thread floating where a very well regarded SS amp blew and took out the unlucky owner’s JBL speakers. I think tube amps are a lot more reliable than many audiophiles give credit to, and SS are not the infallible devices either, perhaps with even more potential for downstream damage (direct coupling!). A lot can go wrong with transistors; they’re mechanically robust but don’t take electrical trauma well - the reverse of tubes!!

I have 3 tube integrated amps between 2 systems - Line Magnetic 518IA, (845 tubes), Finale Audio Mk2 7189A (7189A/EL84M tubes, and an Audio Audio Spirit 2 (KT88) none take 4 hours to warm up; each sounds good after initial 15 minutes of warm up, and very good within the hour. If it took 4 hours 1st I’d look for new tubes andif that didn’t work then I’d be looking for new amps

~20 min for me as well

I've never experienced such a long warmup time with tube gear (usually fine in 20-30 minutes with "maybe" a slight improvement over the next 30 minutes).

Of course the speakers, turntable bearing/cartridge, CD deck, tape deck et cetera were also warming up @ the same time.

This said (since the 70's) I've never owned PP amps with large output tubes (just PP 6L6/EL84/EL34, and single ended EL84/2A3/300B amps).

DeKay

@hilde45 wow -- 4 hours -- wow. So, tube life is, in effect, one quarter of their expected life for good listening? That will sound like an argument for solid state to many.

And if you like your tube amp(s) more, keeping spare tubes around is an option. With extended long term use, and not a common situation, one of my former/older SS amps expired too. Kept a spare SS amp around for back-up parts.

Simple point-to-point tube amp design won for me - - no extinct circuit boards or extinct SS output transistors to keep spares for any more.

My CJ Premier 1B takes about 20 minutes.

Maybe it’s your tubes. My tube amps, both vintage McIntosh, get with it pretty quick, like less than 20 min.

That seems rather long---that wouldn't cut it for me since I rarely listen to my music for 4 hours straight. I don't have tubes but my Sugden A21 sounds pretty sweet after about 15-20 mins.

My Elekit 300B sounds better than most of the other integrated amps on earth after 20 minutes.  But after 4 hours they’re magic.

Had a pair of Gryphon SS Class A monoblocks that peaked at 12 hours even though I kept them in standby all the time.

Go figure.

I agree with @designsfx for ARC stuff.  A half hour definitely benefits it, but I live in SO FL where it is warm most of the time--NOT THIS WEEK!

As far as hours and hours, I don't really notice much difference after a couple of albums.

Cheers!

4 hours -- wow. So, tube life is, in effect, one quarter of their expected life for good listening? That will sound like an argument for solid state to many.

PL Dialogue HP Integrated here. Sublime within 15 minutes of power-up. 4 hours? Sounds like your confirmation bias needs adjustment!

My tube amps seem to warm up pretty quickly...10 to 20 minutes maybe? My Pass XA-25 takes about 45 minutes although it sounds damn good immediately upon start-up.

It took my solid state equipment 4 hours to sound its best.

My current Primaluna Evo sounds great in less than an hour.

It could be equipment that's in front of the Primaluna that needs more time.

But certainly my sense is that tube gear hits its sweet spot sooner than solid state.

My Mal Valve 2 and VAC 300.1 have a good sound after 45 minutes. After 4 hours , they sounds amazing !

My carver black magic take less than 5 minutes to get the bias meter up & stable at 100. It's playing nonstop for the next 6 hours, every single day. Sound starts great & stays there. 

I don’t know how people wait that long. It might warm up a lot faster if you just start using it from the get go rather than leaving it idle. I may watch some tv or better yet blast some cooking music that I can hear from the kitchen. Then, when I’m ready, I’ll switch to triode mode, make my selection, and let the music wash over me. 

My ARC amp/pre need about 30 minutes or it sounds a little thin to me. Every hour after that just gets better and better.

I agree with lancelock. On the LTA design. What a benefit. Think about it over the lifetime of YOUR time. LTA deservingly should be considered with appreciation that often isn’t spoken about. For the Ultralinear, I can listen at the ten minute mark and get full value at about 30. Maybe due to the transformerless design,without noise, or product weight, ez access and inexpensive tube replacement, and the fact that the tubes last far beyond the norm so can remain on and don’t need to wait for any warmup.  What’s wrong with this other than one needs consideration for moderately efficient transducers for this design to ultimately not be a great choice?  

Op, +1 although my amp was more like 3 hours. Or should I say at least 3 hours 

10-15 minutes is great, but after an hour or two I'm often finishing my 2nd hazy IPA and it sounds wonderful! 😂

I have never had a tube integrated amp and I’ve never had a tube preamp take more than 15-20 minutes and an amp take more than an hour to reach the “Sweet Spot “.

Funny you should bring this up. While the system sounds great after 20 minutes, I too have noticed that things get sublime after about 4 hours. All analog and tubes here.

My David Berning designed Linear Tube Audio ZOTL40 takes about 10 minutes to get there.