The folks at SMc Audio recommend leaving their McCormack amps on 24/7. |
Does Hell have Bose Speakers? |
03-05-11: Tmsorosk
Paper ... You may claim thermal switching is B.S. but several manufacturers of equipment I own as well as my long time dealer tell me that leaving things on reduces brake down rate , Iv'e followed there advice for many years and have found this to be true. What do they no eh . Do you no a manufacturer of S.S. equipment that states otherwise . Class A amps that run very hot may be the exception.
if you just took the word of the manufacturer yet don't know what failure is that is being prevented by 24/7 operation, then you don't know whether you are just accepting a bill of goods. if you uniformly believe what you read, then you sound like a prime candidate for $15,000 interconnect cable. the reality is that product failures are often characterized by a "bathtub" curve where there is a period in which you have a higher failure rate early (this is referred to as "infant mortality"), a period where the predominant failures are random failures, and a period where failures result from the product just wearing out. a company that has reasonable quality control processes should screen for infant mortality. this screening is typically referred to as product burn in. this kind of burn in is different from the meaning of "burn in" as used by audiophiles. burn-in testing often tends to weed out infant mortality by testing at elevated temperatures and/or voltages. i can believe that there are manufacturers who don't have such good quality control processes and they ship products out without burn in testing. my amplifier and pre-amplifier are by bryston. one good thing about bryston is that they openly disclose their processes and they describe the burn in process that they follow before shipping products. the company that supplies your products may not do any such burn in. proper burn in testing will have a lot more to do with the likelihood of reducing product failure than this 24/7 stuff that you are repeating. here are the comments from pass labs on product life from one of their power amplifier owners manuals:
So how long will this hardware last? It is our experience that, barring abuse or the odd failure of a component, the first things to go will be the power supply capacitors, and from experience, they will last 15 to 30 years. Fortunately they die gracefully and are easily replaced by a good technician.
After that, the longevity will depend upon the number of operating thermal cycles, but we can say that we have had amplifiers operating in the field in excess of 20 years with no particular mortality, and we dont have good information beyond that.
More to the point, you should not worry about it. This is a conservatively built industrial design, not a frail tube circuit run on the brink of catastrophic failure. If it breaks, we will simply get it fixed, so sleep well.
what pass describes is a wear out failure mode (capacitors) and the possibilty of random failure (which they say they will fix).
03-05-11: Tmsorosk
And as far as a sonic difference goes , my own ears as well as other well respected audiophile friends have tested the affects of turning off large power amps and the results are consistent , etched sound for hours to days , one of the few things we agree on . Have you done such tests for your self , Or are you a theoretician.
the reason why i mentioned theory was to suggest that the stuff about how equipment sounds better after warm up may not be complete bs - that there is some theoretical basis for the claims. for my own part, my view is more like that of cmjones: after 15 minutes i'm not going to remember how the system sounded then with enough detail to make a meaningful comparison with how the system sounds later. |
Mcintech, I recently talked to a tech who told me that long storage can be far worse on the caps then leaving a piece of gear on 24/7. |
03-05-11: Hifihvn
The link to a post Almarg pointed out covers the way it is IMO. Some electronic components (semiconductors) do not like the big thermal swings, and may fail sooner. Others may settle, and break in to the on always operation since they stay hot all the time. With this case, those semiconductors may break when they shrink during cool down, since they have never been allowed to contract during a cool down, and expand during warm up, since this is what they have become accustomed to. Think of it as a super miniature bridge without expansion joints, for thermal change, while others may handle the temp swing like a bridge. That one poster is an engineer(Almarg link) that specializes in this. And like he says, it varies from component, to component. I'd have to agree with that. It makes sense.
i have not read the almarg posting to which you are referring but the failure mode to which you are referring is highly unlikely in practice because semiconductor manufacturers typically manufacture devices to iso 9001 standards. so they do burn in testing to screen out the kinds of failures that you describe (which are typically "infant mortality" type failures) [i briefly described burn in testing in another posting but burn in testing by electronic manufacturers is different from "burn in" testing as the term is used by many audiophiles]. furthermore, semiconductors are tested over a temperature range that is wider than they are likely to encounter in actual use. but failures can occur at various stages. the semiconductors are assembled onto boards and the boards are assembled into systems. burn in testing would need to be done to screen for infant mortality at each stage. a given audio equipment maker may not use such quality control processes (it does after all increase costs because some products will fail) but bryston does do burn in testing before shipping products (according to the information on their website). |
I should have emphasized that I was referring to vintage gear (my specialty, and what I listen to at home), and since I typically like to buy once (I drive a 16 year old Corolla) long term reliability is paramount 'cause this boy don't like to repair his own gear.
The Nagra pyramids run so cool I doubt you'd see heat damage for over 10 years or more.
My shop is also McIntosh Labs and several other brands, and the same applies. After SEVERAL years, you can tell which units never get turned off, even CD players in the power supply areas.
If you only keep new units for a few years, leave it on. |
Paperw8, This thread and post was the one I believe. [http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1296956886&openfrom&13&4#13] |
03-08-11: Hifihvn
Paperw8, This thread and post was the one I believe. [forum.audiogon#13]
i read the comment by cathode and while i won't dispute the *possibility* of anything that was suggested, i frankly didn't find much usable information in the posting. |
Not being an EE, I can't say for sure, but I don't think home audio even has a 100% duty cycle. Most power amps usually don't to my knowledge. So I guess it's how the engineer designed it. |
follow the manufacturers' instructions, as he or she is the best judge of optimizing the life and sound of a component.
it seems intuitive to leave all solid state gear on all the time, but ii'm sure that not all manufacturers would agree. |
What Mcintech said about the wine was seriously funny.
I am an EE and have been one for over 30 years with analog/digital and amplifer/filter design and test background. I am also a state registered Professional Engineer. Go figure. However, I will state again, Leave your equipment off until you are ready to listen. Turn it on with sufficient time to properly warm up and begin listening. When a signal begins to flow through the system the warm up time is faster. Except for pure class A equipment, which, depending on the bias points (and class A means different things to different Engineers), may be faster than others. As others have mentioned, pc boards get brittle over time with heat. Other components were not designed, nor tested (trust me) to be operated "on" 24/7. Look at any serious audio magazine. Do they review or rate your older (more than 2 years old) equipment? most times not. So, manufacturers have to have their products in the magazines in order to make money (in their opinion). So they have come up with the latest and greatest and newest equipment. Which in many cases is really not better than the older stuff they produced. But, their names will not get mentioned in mags, nor reviewed unless the equipment is "new". So, they really want you to either 1) buy their newer stuff, or 2) bring it in for repair. Would you think that audio equipment is treated any diffently than cars? Dealers make their money on maintenance, not sales. Most high end equipment have soft start circuitry that seriously reduces the chance of turn on failure. My equipment stays off until I come home from work and then I turn it on, do a few things around the home, and then I sit for my enjoyment.
That said, enjoy |
One can have enough degrees to be a thermometer(I only got two at Case Institute), and they will do ABSOLUTELY NOTHING for the individual's aural acuity, or their system's resolution(just two of many possible variables). My BAT VK-D5 CDP has a, "Standby" feature, that keeps the circuits/tubes warmed up at half voltage(designed that way, by BAT's resident Rocket Scientist, OBVIOUSLY for a reason). My SS bottom end amp, TacT pre, and Phono pre, stay powered up 24/7. My tubed mains amps are powering up at least an hour before listening. I'm certain Julian Hirsch(of Everything-sounds-the-same fame) would be proud of those that can hear no differences in well warmed up gear(or perhaps: have never heard well warmed up gear). BUT- As long as YOU are happy with your system's presentation- HAPPY LISTENING! |
Indeed, an amp manufacturer will rightly claim the amp sounds better left on, and until it fails I'm sure it does. A car runs better when warmed up...leave that car on! If my gear is on and nobody is listening, does it sound good? Hmm... |
Wolf ... Most taxi's are left running . Ever wonder why taxi's get into the million mile or more mark ?
Our cat hates being left along , if she see's we are getting ready to leave she will run to the listening room and curl up in the sweet spot and hardly notices were gone .
We don't want to anger the animal activist's there likely tougher than the environmentalists . There's no keeping everyone happy . Ya-Ya I know thats a pretty lame excuse . |
I think people give way to much credence to what the manufacturers say, specifically to reliability and turning the amp off or leaving it on. I'd bet most have no hard data to prove either way, it costs a lot of money to do those types of studies and it takes a long time. There is no reason for a manufacturer to incur those costs.
If they told everyone to turn it off when not in use, there would be some portion of the user population that would turn off / on multiple times each day. This is what they're probably trying to avoid by telling everyone to leave on 24 x 7. That, and it sounds sexier if you are told that the amp you just bought "Needs to be left on to sound its best." |
Tinsorosk - If Taxis are left running it's because the driver wants to stay warm.
And I don't think any cab hit 1 million miles, it is certainly not routine. (Wiki says one of the 20-year old Checkers got almost 1 million miles, probably with a few overhauls). |
>>03-09-11: Sebrof
I think people give way to(sp) much credence(sp) to what the manufacturers say<<
Good point.
It would be silly to think the manufacturers know more about their products than you. |
Having spent most of my life my repairing car's including taxi's , I can assure you they get many times the miles we do . I am vigilante with maintenance , keep are cars in the garage , lot's of T.L.C. And I still can't get near the milage those broken down wrecks could . One driver told me he left it running because if it didn't start he would lose a few fairs .
Any cab drivers out there want to chime in for another prospective .
Hit me with music
Tim |
03-08-11: Rodman99999
One can have enough degrees to be a thermometer(I only got two at Case Institute), and they will do ABSOLUTELY NOTHING for the individual's aural acuity, or their system's resolution(just two of many possible variables). My BAT VK-D5 CDP has a, "Standby" feature, that keeps the circuits/tubes warmed up at half voltage(designed that way, by BAT's resident Rocket Scientist, OBVIOUSLY for a reason). My SS bottom end amp, TacT pre, and Phono pre, stay powered up 24/7. My tubed mains amps are powering up at least an hour before listening. I'm certain Julian Hirsch(of Everything-sounds-the-same fame) would be proud of those that can hear no differences in well warmed up gear(or perhaps: have never heard well warmed up gear). BUT- As long as YOU are happy with your system's presentation- HAPPY LISTENING!
the thing that i find so ridiculous about some audiophiles is that you have people, like the one above, who admit that they don't know what they are talking about, but energetically argue their position because "the manufacturer says..." it would be like energetically arguing the existence of the tooth fairy because your parents told you she existed and the "proof" is that you left a baby tooth under your pillow and later found $1 in its place. audiofeil likewise seems to express an unquestioning faith in the statements of audio equipment manufacturers. the problem with this kind of reasoning is that it fails to ask what could be motivating the manufacturer to give such advice. i mean, really...would you buy a used car based on this kind of reasoning?!? here's how it works: audiophile makers too often advocate for massive waste for little benefit. here, the idea is that you run equipment 24/7 so that you can sit down and obtain better listening without having to wait 15 minutes. so the proposition is that you would leave the equipment powered up for, say, 20 hours unused so that when you do sit down to listen you can save the 15 minutes of warm up time that you would have to wait if you powered up at the time that you started listening. |
03-09-11: Tmsorosk
Wolf ... Most taxi's are left running . Ever wonder why taxi's get into the million mile or more mark ?
tmsorosk - taxi drivers can't afford to act like some audiophiles; they have to live in the real world...at $4/gallon, you don't leave a taxi running any more than you have to. |
paperweight- Who was it that admitted they don't know what they are talking about? Certainly NOT ME! I've probably forgotten more about audio gear, than you will ever know. I've been building, modding and repairing pro and home equipment for over thirty years(the better part of that time: professionally). NOR did I say, "the manufacturer says." What is TRULY, "ridiculous", is your lack of comprehension skills. My reason for leaving SS gear on, is the sound quality(which is everything to me), rather than longevity. Everything simply sounds better that way. If you can't hear any difference, or are simply satisfied with your mediocrity; What do I care? Like I said, "HAPPY LISTENING!" |
03-09-11: Rodman99999
paperweight- Who was it that admitted they don't know what they are talking about? Certainly NOT ME! I've probably forgotten more about audio gear, than you will ever know. I've been building, modding and repairing pro and home equipment for over thirty years(the better part of that time: professionally). NOR did I say, "the manufacturer says." What is TRULY, "ridiculous", is your lack of comprehension skills. My reason for leaving SS gear on, is the sound quality(which is everything to me), rather than longevity. Everything simply sounds better that way.
if you can't explain why the equipment needs to operate 24/7 to "sound better" then you don't know what you are talking about, regardless of any claims that you might make. things don't happen by magic, so if what you are stating is true, then there must be some reason. on the other hand, if the reason is a purely subjective one, as you have advanced, then it is pretty much discussion over...i mean, if you subjectively believe in the tooth fairy, then that's just what you believe. |
03-09-11: Audiofeil
>>03-09-11: Sebrof
I think people give way to(sp) much credence(sp) to what the manufacturers say<<
Good point.
It would be silly to think the manufacturers know more about their products than you.
Never said I new more, I just said they're is little reason for the manufacturer to do the test so in most cases they do not, and that their are other reasons for releasing statements two customers then what mite look at face value. |
|
NOR did I say, "I can't explain why." There are numerous reasons. ie: It takes some time for the dielectrics within capacitors to fully form/absorb their charge, once they have been discharged(http://www.designers-guide.org/Modeling/da.pdf), and they WILL NOT sound the same, before and after. The better the dielectric(ie: Teflon, polypropylene, polystyrene), the longer that process takes. Regardless of what facts are presented; those of you that are concrete(thoroughly mixed up, and completely set) in your beliefs, will NEVER be convinced! Why bother trying? Tooth Fairy? One thing of which I AM now fully convinced: YOU are King of Unfounded Assumptions(especially regarding others, their knowledge, experience and capabilities. |
03-09-11: Rodman99999
NOR did I say, "I can't explain why." There are numerous reasons. ie: It takes some time for the dielectrics within capacitors to fully form/absorb their charge, once they have been discharged(www.designers-guide), and they WILL NOT sound the same, before and after. The better the dielectric(ie: Teflon, polypropylene, polystyrene), the longer that process takes. Regardless of what facts are presented; those of you that are concrete(thoroughly mixed up, and completely set) in your beliefs, will NEVER be convinced! Why bother trying? Tooth Fairy? One thing of which I AM now fully convinced: YOU are King of Unfounded Assumptions(especially regarding others, their knowledge, experience and capabilities.
the article that you cited about dielectric absorption was quite interesting and all, but did you actually read the article before you cited it? as interesting as it is, i don't see how it is of any relevance to this topic. the reason why the author was concerned about dielectric absorption was for its effect in sample and hold circuits. i can see how that would be relevant to someone designing a high-speed sample and hold circuit, but i don't see how it is relevant to audio equipment [for example, the article refers to a capacitance model that has a frequency pole in the 20MHz frequency range]. nor, for that matter, is there any suggestion in the article that dielectric absorption has anything to do with powering on/off equipment. am i convinced by your arguments? no, i'm not. i don't know what you know, but from my perspective, your use of grammatical histrionics in your postings makes me suspicious that you are trying to rely upon histrionics in lieu of substance. i don't find that kind of "I KNOW WHAT I'M TALKING ABOUT!" argumentation to be very persuasive; i'm much more likely to believe a well reasoned argument (one that sets forth a logical basis for the conclusion) instead. |
Blah, blah, blah! Again- your being comprehensively challenged, has revealed itself. The very first paragraph of that treatise states, "Less appreciated, but no less important, is the
role it plays in determining the quality factor, or Q, of the capacitor. Dielectric absorption
has both storage and loss components that act, and are significant, over the entire
usable frequency range of the capacitor." That audio signals are much more complex, and their components more delicate, than anything that might pass a sample and hold circuit, obviously escapes you. Nor am I surprised that you do not understand how DA would relate to powering a circuit up and down. I believe I mentioned that, regardless of facts presented; I would not expect one such as you, to be convinced, in the least. It seems I have entered a battle of wits, with an unarmed individual. Enjoy, "The Last Word." You have become quite tedious. |
paperweight- let me rephrase something: Make that, "Comprehensively comprehensionally challenged", just for clarity. |
03-09-11: Rodman99999
Blah, blah, blah! Again- your being comprehensively challenged, has revealed itself. The very first paragraph of that treatise states, "Less appreciated, but no less important, is the
role it plays in determining the quality factor, or Q, of the capacitor. Dielectric absorption
has both storage and loss components that act, and are significant, over the entire
usable frequency range of the capacitor."
i sensed that your reading of the article was quite superficial - you should have read more of the article.
03-09-11: Rodman99999
That audio signals are much more complex, and their components more delicate, than anything that might pass a sample and hold circuit, obviously escapes you.
if you actually believe that audio signals are too "complex" and too "delicate" for sample and hold circuits, then i strongly suggest that you to do some investigation to find out how they digitize audio signals for cd's, vinyl, computer audio and other audio media. if you do it right, you'll be surprised at what you will find out...
03-09-11: Rodman99999
Nor am I surprised that you do not understand how DA would relate to powering a circuit up and down.
i get the strong impression that you don't either. |
03-09-11: Rodman99999
"Blah, blah, blah! "
You could have stopped there The rest of your post was redundant. |
Breaking Gnus!
More bad Gnus. 15 million people at risk. Slow moving heavy rain storm, today through Friday, Texas to Arkansas. 25 tornados (count em!) and flooding hits the South. Ten states involved.
|
Since the number of audiophiles worldwide represent less than 1% of the population - NO measurable effect! Now about those billion motor vehicles ... |
Hi,
a well broken in equipment will come alive faster after turning on. I never leave them on when away or not having a long listening session. Most high end units have a soft start so no big harm there. In absolute terms leaving a unit 24/7 on will not bring a longer life as you will need a more frequent change of caps, tube replacement, change of equipment and a heavier electricity bill. |
