jnorv Posted February 17, 2002 Share Posted February 17, 2002 Any advice on breaking in new power tubes? I have a pair of 300B's on order. Is it better to just turn on the amp for a long period or is normal listening better? Jim Norvell Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted February 17, 2002 Share Posted February 17, 2002 Just play the beasts... Just realize that some tubes (and this time is variable) need awhile to sound their smoothest. Dont worry about it - just start listening to your music; it will take care of itself. kh Quote Link to comment Share on other sites More sharing options...
arco Posted February 18, 2002 Share Posted February 18, 2002 Mobile is correct... Just keep in mind that some 300B tubes (WE included) need more than 200 hrs to sound their best! If you ever decide to "shorten" the break-in time by leaving the amp playing continuously, just remember to shut it off from time to time. Tubes also need a number of complete thermal cycles to properly set-in. Aristidis www.aca.gr/pop_coumpas.htm Quote Link to comment Share on other sites More sharing options...
edster00 Posted February 18, 2002 Share Posted February 18, 2002 FWIW in the owners manual of my (previously owned)Decware Zen amps the instructions were: Turn them on and let them run for 5 hrs. then off 5 hrs, repeating the cycle 5 times. He said he would recommend that for all tube amps. I don't know if the actual time is really significant, except to the extent that arco stated regarding thermal cycles. ------------------ 2 Channel System: '78 Khorns w/ALK networks Welborne Labs Moondog 2A3 amps AES AE-3 Superpreamp DJH mods McIntosh MCD 7007 CD McIntosh MR-78 Tuner DIYCable Twisted Cross Connects DIYCable Superlatives (preamp/amp) DH Labs Silver Pulse interconnects (sources/preamp) f> s> Quote Link to comment Share on other sites More sharing options...
lynnm Posted February 18, 2002 Share Posted February 18, 2002 FWIW My AQ1003DT sounded great the first time I used it and now after a few hundred hours of use it sounds even better or perhaps my listening equipment has gotten tuned up. In any event as MH says just play the damned things and enjoy! ------------------ It is meet to recall that the Great Green Heron rarely flies upside down in the moonlight - (Foo Ling ca.1900) Quote Link to comment Share on other sites More sharing options...
WMcD Posted February 18, 2002 Share Posted February 18, 2002 I can't imagine that anything you'll do will make things better or worse. This whole issue seems very odd to me. In the days when tubes were the only amplifying devices, I never saw any claim of changes in parameters in the first hours, 10's of hours, or 100's of hours. Even today, I've not seen anyone run a curve on performance, let it sit on the checker for 20 hours, and then the performance is different. Gil Quote Link to comment Share on other sites More sharing options...
soundog Posted February 18, 2002 Share Posted February 18, 2002 I seem to remember in the old days that some claimed it was better to leave tubes always on because they sounded better than when you turned them off and had to warm them up ...not sure if that was just for the preamp or for the whole system ... I always had to turn them off or my parents would be upset .. but I do recall they sounded better after listening for an hour or so ... but Gil is right there was NEVER any mention of break in or burn in periods for anything AND everyone used run of the mill wire - NEVER a mention of improving sound via wire - wire was wire. I do remember saving for matched pairs of EL84s however. ------------------ Soundog's HT Systems This message has been edited by soundog on 02-18-2002 at 10:24 PM Quote Link to comment Share on other sites More sharing options...
jnorv Posted February 19, 2002 Author Share Posted February 19, 2002 Audio Research (http://www.audioresearch.com/) claims to burn their's in for 48 hours before matching them. Quote Link to comment Share on other sites More sharing options...
Allan Songer Posted February 19, 2002 Share Posted February 19, 2002 I was reading this with real curiosity and decided to do a little test. I un-plugged my quad of GEC KT-66 in my MC-30s that have about 10,000 hours on them and replaced them with four NOS that I've had sitting around here for more than 10 years (but from the same "batch" of 12 I bought in the 80's). Sound different? Not really--perhaps a little more strident, but so little a difference I can't really say. Am I deaf? Quote Link to comment Share on other sites More sharing options...
mike stehr Posted February 19, 2002 Share Posted February 19, 2002 http://www.svetlana.com/docs/tubeworks.html Scroll down to Tube assembly. It explains the Sealex type tube processing machine, and how they are processed and fired up. They use a RF Induction coil around the tube to get the Impurities out of the metals, I think before they pinch the vacuum on the tube. This has nothing to do with audible break-in. But I wonder why if Tubes just break-in right away a few turn-off turn-on cycles, then why are vintage NOS tubes most desired? The materials used in the old NOS Tubes? Quote Link to comment Share on other sites More sharing options...
Chris Robinson Posted February 20, 2002 Share Posted February 20, 2002 Good article, MH ... and the Svetlana link was good too. If you missed the link on the Svetlana page, it's good general background reading as well. http://www.spectrum.ieee.org/select/0898/tube.html ------------------ If you don't like what is coming out, you wouldn't like what is going in." -PWK- --------------------- HOME THEATER Klipsch 1968 ALK Cornwall "II"s (LF/RF) ALK Belle Klipsch (Center) Klipsch Heresy (RR/LR) Klipsch KSW-12 sub Sonic Frontiers Anthem AMP1 (driving Cornwalls) Sonic Frontiers Anthem AMP1 (driving Heresy's) Denon AVR-4800 Toshiba SD-3109 DVD TWO-CHANNEL SYSTEM AES AE-25 "Superamp" AES AE-3 Pre-amp New Tube 4000 CD Player 1976 Klipschorns (ALK'ed) Quote Link to comment Share on other sites More sharing options...
WMcD Posted February 20, 2002 Share Posted February 20, 2002 In the late 60's and early 70's I was into building Heathkits and amateur radio. So I was not working with the real design theory. Still. I have never run across any technical spec from a manufacturer of tubes, transistors, caps, inductors, or resistors, which even hints that values change with "burn in". If there is a mil spec on this sort of thing, I'd like to see it. It may be that at the factory, such items are QC'ed, or run under load for a short time to check "infant mortality". It is tough to disagree with owners who find better results from a system after, say, 30 hours of listening. None the less, there just does not seem to be any technical basis for it. I'd be pleased to see any amp review with measured specs at 1 hour, versus 100 hours or anything else. The bottom line, for me, is that there are no data to suggest that the performance of individual components change with "burn in". Further, if one has an amp with 100s of components, there is no hard data to suggest that the overall system response changes either. It is interesting to observe that no one has suggested that either electrical components or overall systems sounded better at the start, than after 100 hours. By some ways of thinking, wouldn't things get worse in time, rather than better? I conclude the problem is not in the electronics, but in our heads. Gil Quote Link to comment Share on other sites More sharing options...
Randy Bey Posted February 20, 2002 Share Posted February 20, 2002 I certainly have no definitive knowledge of this topic, but I ask myself this, of which I do have first hand experience: Does a new engine run better than one with 5000 miles on it? I would say yes, it does. This has to do with 'seating' of materials, such as the pistons to the cylinders, and probably other processes only marginally understood, but accepted by most gearheads. The engine is still doing what it was designed to do, spark plugs firing, gas exploding, crankshaft turning, but at 5000 miles it does it 'better' than when brand new. Consequently it is not a leap of faith to assume that electronic components also 'seat'. It is also not a leap of faith to assume that the electron-swingers don't know all there is to know about resistance, capacitance and inductance. Quote Link to comment Share on other sites More sharing options...
Chris Robinson Posted February 20, 2002 Share Posted February 20, 2002 I can't comment on tubes since I'm a newbie to this thing ... but on components, I've been selling them for 20 years and have been through my fair share of manufacturing facilities with customers doing audits, etc. Gil is right ... the main thing is fighting the "bathtub curve", which basically plots the probability of failure (Y axis) vs. time (X axis). The Y-values are highest when the X values are low and high, and low in between (kind of looks like an old footed bathtub). Basically they fail mostly when their young (weeding out the bad ones) and old (dying of old age). Some components got extra-special attention. We (Philips) used to make tight tolerance resistors for the military, and those were carefully screened through lot sampling and lengthy burn-ins to achieve their MIL rating. Tantalum capacitors (conformally coated, low ESR especially) also got close scrutiny because the failure mode (these were non-fused) was spectacular. Nothing got the attention of a customer faster than holding up a $6000 backplane, loaded with ASIC's and connectors, with a hole shining through it caused my the intense heat of tantalum burning Anyway, most of the data collection in the factory and field went to determining FIT data (failures in time) so the reliability of the device could be anticipated. Modern silicon really doesn't have that problem; it rarely fails unless it is susceptible to ESD or takes a catastrophic power surge. Discrete devices that run hotter (power transistors, FETs, etc.) are a little less reliable but are usually weeded out in final test after manufacture. Allan's comment that he's got 10K hours logged on his tubes would lead me to believe that tubes can last a long time if you're past the infancy period and have a good tight vacuum. That being said, one of the Chinese KT-88's that came with my SuperAmp six weeks ago failed in the first 50 hours and the entire quad had to be replaced. I have a quad of Marconi TT-22's on order (50's NOS) that will hopefully do a little better! ------------------ If you don't like what is coming out, you wouldn't like what is going in." -PWK- --------------------- HOME THEATER Klipsch 1968 ALK Cornwall "II"s (LF/RF) ALK Belle Klipsch (Center) Klipsch Heresy (RR/LR) Klipsch KSW-12 sub Sonic Frontiers Anthem AMP1 (driving Cornwalls) Sonic Frontiers Anthem AMP1 (driving Heresy's) Denon AVR-4800 Toshiba SD-3109 DVD TWO-CHANNEL SYSTEM AES AE-25 "Superamp" AES AE-3 Pre-amp New Tube 4000 CD Player 1976 Klipschorns (ALK'ed) Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted February 20, 2002 Share Posted February 20, 2002 Almost ALL tube manufactures, capacitor manufacturers, gear manufacturers, etc now recognize the importance of burning in the equipment and/or allowing proper warm up before serious auditioning. Many now include notes in their manuals concerning this aspect. This is now almost common knowledge and I am surprised it still gets nixed anywhere but the most basic audio forums. I personally have heard this so many times, it is not even a question. And although one does get used to the sound, it surely is not the sole reason for the differences in sonics. I will agree with Chris that a major benefit to burn in at the factory is the test factor and the correctly identified point that problems with the component can be caught. IT is very true that if most components make it past those initial stages, then the chance of failure are greatly reduced. However, it is common knowledge that caps burn in and become formed. The same can be said for circuitry. I have not a doubt in my mind that components and wire change in sound during the first week or so of usage. I have heard this so many times, as stated, that it is a moot point to me. If you need tests, data, and studies to prove this phenomenon, or have not witnessed as much, or attribute all of this to the mind becoming acclamated, then you can begin enjoying your component(s) right away, with a smile wide and sincere. However, I personally would have taken back more than a few components if this was the case. My Rega CDP, though used, had only a few hours on it. I have NEVER seen a component take so long to smooth out and open up! It sounded constricted, confused, with no soundstage. It sounded like the worst of digital had come to roost except without the any air at all! A month passed by, and the unit was STILL improving although much less so after the first week. The same can be said for my Sovtek 2A3 tubes, which sounded closed in and none too smooth. When you have a single-ended amp that is so revealing, and everything else in the chain exposing subtle shadings, then something like this gets driven home. One of the most controversial components that REALLY can sound like utter dreck brand new, is cable. Christ, I dont want to bring the loons from everywhere on this, but some wire out of the box sounds so closed in and lifeless, it is PAINFUL. Save the objections for another thread, however. I am just talking of my experience with the many cables I have had on hand. That is why more than a few manufacturers and dealers now have devices like the MOBIE to break in wire with a signal to drop the burn-in time and customer returns. OF course, saying as much within here is almost a lost cause... Yet, say it I will. The disbelievers can feel content that they are not being duped. kh Phono Linn LP-12 Vahalla / Linn Basic Plus / Sumiko Blue Point CD Player Rega Planet Preamp Cary Audio SLP-70 w/Phono Modified Amplifier Welborne Labs 2A3 Moondog Monoblocks Cable DIYCable Superlative / Twisted Cross Connect Speaker 1977 Klipsch Cornwall I w/Alnico & Type B Crossover system one online / alternate components / Asylum Listing f>s> This message has been edited by mobile homeless on 02-20-2002 at 11:05 AM Quote Link to comment Share on other sites More sharing options...
Chris Robinson Posted February 20, 2002 Share Posted February 20, 2002 mdeneen, points taken. Let us eschew obfuscation (horatory subjunctive to boot). MH, a definitive post, as we've come to expect from you. Thanks for all your time and contributions. You've raised the water mark so many times. ------------------ If you don't like what is coming out, you wouldn't like what is going in." -PWK- --------------------- HOME THEATER Klipsch 1968 ALK Cornwall "II"s (LF/RF) ALK Belle Klipsch (Center) Klipsch Heresy (RR/LR) Klipsch KSW-12 sub Sonic Frontiers Anthem AMP1 (driving Cornwalls) Sonic Frontiers Anthem AMP1 (driving Heresy's) Denon AVR-4800 Toshiba SD-3109 DVD TWO-CHANNEL SYSTEM AES AE-25 "Superamp" AES AE-3 Pre-amp New Tube 4000 CD Player 1976 Klipschorns (ALK'ed) Quote Link to comment Share on other sites More sharing options...
jnorv Posted February 28, 2002 Author Share Posted February 28, 2002 I got my new 300B TJ mesh plates installed last night. They sound pretty good right off the bat. Much better base than the Valve Arts that I replaced.I have no complaints about their sound. If they get better with age, then lucky me. Jim Norvell Quote Link to comment Share on other sites More sharing options...
Klewless Posted March 1, 2002 Share Posted March 1, 2002 Hang in there guys, But I think a great way to break-in tubes is with a hammer. (Works pretty well with transistors too.) Sorry.......Just had to say this. jp ------------------ John P St Paul, MN Quote Link to comment Share on other sites More sharing options...
dubai2000 Posted March 2, 2002 Share Posted March 2, 2002 Jim, can you please add a few more words about the sound of the TJs? Although I have just got a pair of Svetlanas (really beautiful sound btw) I am curious when it comes to those TJs. I know that mobile is not taken too much with them, but some more info might either cure me or make me rush to the bank (if only they were less costly...). Thanks. Wolfram ------------------ Khorns, tubes and a suitable room: Welcome to aural paradise! System: 1973 Khorns with ALK crossovers REL Stadium II sub Cayin 743 D integrated tube amp McIntosh MR 77 McIntosh MCD 7007 Thorens 520S SME 3012-R Ortofon SPU Classic GM E Cyrus aEQ 7 phono stage with PSX-R power supply Alternative system: Quad ESL 63 McIntosh MC 2105 McIntosh C29 Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted March 2, 2002 Share Posted March 2, 2002 Remember, I did not audition the TJ 300B Meshplates referenced above per say. The tubes I had were the TJ 300B/2.5v version which is essentially the same tube yet run at 2.5v so it would be a direct drop in for the 2A3. I listened to these tubes in Wright Sound and Welborne Labs 2A3 amps. I have not auditioned the regular TJ 300B Meshplate for 300B amps. The TJ 300B/2.5v version was NOT my frist choice (or even second) for various reasons. I will be listening to the 300B voltage version when the Opera/Consonance Billie gets here. I might have some more comments on that tube after living with it for a bit. kh ------------------ Phono Linn LP-12 Vahalla / Linn Basic Plus / Sumiko Blue Point CD Player Rega Planet Preamp Cary Audio SLP-70 w/Phono Modified Amplifier Welborne Labs 2A3 Moondog Monoblocks Cable DIYCable Superlative / Twisted Cross Connect Speaker 1977 Klipsch Cornwall I w/Alnico & Type B Crossover system one online / alternate components / Asylum Listing f>s> Quote Link to comment Share on other sites More sharing options...
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