I searched the forum for break in time. It seems people don't think ther is one. Well if there isn't this is comming back. In Home theatre it was very impressive. Definetly outperformed my Integra DTR 5.3 by a wide margin. But for music it's just not very good. It sounds grainy and not very musical. Some things like clarinet and sax sound good. But other horns are irritating. Rock is also grainy sounding. It's just not very pleasurable to listen to. My integra sounds so much more musical. I think the bass could be more adjustable also. I have it turned all the way up and I still think I need more. The reason being the mids are too prominent foy my taste. I have very revealing Axiom speakers. Also I got shorted on my cables and I called my sales rep and haven't heard back on the issue. I'm using some G-snakes for cables from the pre to the amp for now. So one of my Turn Tables is down.

When I got my original 950 (April '02) and my red dot revision (August '02), I didn't notice any break in time. With the blue dot, which is what all 950's are now, I thought there was some break-in -- in the range of a week or so. Don't count it out immediately, hopefully it will come around for you.

There is no such thing as "break-in" with modern solid state electronics. It is an audiophile myth.

How do you know? I have a Dynavector P-75 phono stage that took a long time o break in. Or so it seems. It used to be hard to listen to as I would get fatigued after awhile. So your saying I just became def in the frequency that was bothering me?

I've been designing and using audio equipment in my career for over 30 years and have never heard or measured any difference at all in the sound or performance of properly performing solid state (or IC op-amp based) electronics gear over time. Vacuum tube equipment does change it's sound over time for various reasons, but that mechanism is clearly understood.

I might ask, how rigorous a before/after comparison did you perform? Did you keep an "unused" example of your preamp for A/B comparison to the used one? If you did, was the comparison strictly double blind with the levels matched? Additionally, did you consider that your phono cartridge or the records themselves could have changed (worn) over time, and thus their sound would have changed? Both of these being mechanical in nature, such a change is possible.

It is far more likely that the "break-in" is simply your ears getting used to the sonic signature of your preamp as time passes.

If you are hearing a genuine change of the sound of a solid state component over time, that means that something in the circuit is changing, and that certainly is not good! A good design strives to remain stable over time, and unstable circuits are just not the norm.

I also might ask, how come every instance I hear about where somebody said their component had a "break-in", the change was always for the better? That doesn't make sense, wouldn't you think?

Well my phono cart did have a long break in so that could have been it. My dealer told me that solid state has a longer break in than tubes. But he is a flake so I can't take his word as gospel. So when preople say thier solid state gear broke in then it must mean thier hearing was damaged making them able to tolorate the offending frequency. What are you useing to test. Can the instrument be set at a location where the user sits and pick up everything as well as the human ear?

My ears are ringing from listening last night. didn't even turn it up that high. I'm going to try setting the speakers to small as the gentleman from Outlaw suggested. We'll see if that helps. I got a call this morning and they are sending my cables.

"Getting used to" is not the same as "damaged".

Ok. I experimented with the crossover and speaker settings and there is a huge improvement in the bass. It's strange though as my front speakers are Axiom M80's which are supposed to have alot of bass. But the bass is increased dramaticaly by setting them to small sending alot more signal to the sub. I also have full sized rears which I had set to large. All my speakers are now set to small at 60 hz. It's still a little cold sounding but not nearly as bad as before. I think one of the reasons why this was a problem is changing settings isn't instantamious. Theres like a two second delay whan making changes. You always have to remember to make a change and wait to hear what happens. If you don't your way off with what you were looking for.

Not strange at all. "Full sized" speakers rarely, if ever, reproduce bass as well as a decent subwoofer. There you go: instant break in.

And a big reason for that is the optimal location for the speaker to reproduce the rest of the frequency range is very rarely the same as for optimal bass reproduction. Even if the mains have powered subs, a separate sub of equal quality will reproduce the bass as good or better because you can find a more optimal location for it. You're one lucky dog if the optimal place for both is the same place.

"It's strange though as my front speakers are Axiom M80's which are supposed to have alot of bass. But the bass is increased dramaticaly by setting them to small sending alot more signal to the sub. I also have full sized rears which I had set to large. All my speakers are now set to small at 60 hz"

As it was noted above by sdurani, there are very few speakers that can handle the bass as well as a good dedicated subwoofer. You may also find that setting the crossover higher, even as high as "gasp" 120 hz, may improve the response. It is worthwhile to play with different settings. There are a lot of variables in a normal environment setup, we do not live in an anachoic chamber.
I have a 1050 upgraded from a JVC, and I found that the greatest difference, "improvement", came when I changed my speakers; from a varily expensive set to some wonderful diys. I think speakers are the most important part of a system, yes even though a system is made of various intergal parts.

Okay, I'll stick my head out and lay it on the block. My home theater has been in operation for about one month. New 950 & 7x M200. Speakers, cables, and DVD player have many hours on them. At first my system sounded thin and bright. I was disappointed. After one week, probably less than 10 hours, I played a CD that had been used several times during the previous week. To my ears, the system sounded much improved. No scientific study was performed.

"Not everything that can be counted counts, and not everything that counts can be counted." - Albert Einstein.

Certainly a smarter man than me.

Does burn-in exist on some or all solid state components? Beats me. Intellectually, I tend to side with the technical arguments that suggest that it is unlikely (unlike components like speakers, where mechanical parts can experience a physical "breaking in," burn in of solid state components is less explicable). On the other hand, I have heard and read a significant number of reports of people experiencing "burn-in" type changes in equipment and as noted above I could have sworn I heard a subtle sonic evolution with the blue-day 950 that I did not encounter with earlier designs (although one could argue that this was due to my ears adjusting to the design changes). In the end, I think perhaps the best approach might be the following: give new gear that seems a bit "off" time to settle in to the system, if only to give yourself time to finesse settings such as bass management - setting changes that can significantly alter a piece of equipment's behavior (as experienced above by SirAnthony).

Fair enough. My system sounds different to me depending on the mood I'm in or how tired I am. The important thing is not the difference in perception but the reason for this difference. Some will claim that solid state equipment goes through enough of a physical transformation during normal use that it actually produces an audible change (always for the better, stops when it's optimal, never going too far). Others will say that we're simply getting used to a new piece of gear. I guess we each have to decide for ourselves which of those two scenarios sounds more real-world plausible and which sounds more fantastical.

Burn in is real!!! I just experienced it with the Cambridge Audio Azur 640c CD player I just got. At first it sounded good but there wasn't any depth. After about two days running it continuiosly the sound was much improved. Bass tightened, treble improved and depth improved. And adding a better power cable helped too. The thing is.. I don't think break in is so dramatic that the overall character will change that much. If you don't like it at all.. Breaking it in won't help. The 950/755 combo was a bad match for my Axiom speakers. I returned it. Sorry. Now if they would sort out the charges for the missing cables I never got this audition will have only cost me a couple of hundred bucks. I do have a couple of cables to show for it.

Gently putting forward some questions for those that believe in “break in” in those items that do not undergo physical changes with use:

When you say that the performance of a piece of electronics changed over time, are you assuming that your ear/brain analyzer is a “constant state” device and that changes in perceived performance can be wholly or largely attributed to the equipment only?

Was everything in the room, including the exact location of your ears, unchanged during the comparison time? I once was listening to some very familiar music in my car. After a while I straightened my posture which raised the position of my ears and inch or two. Because I was paying close attention to the music, the change in perceived system performance was quite noticeable, yet nothing about the system or the environment itself changed.

Specific test equipment exists that can monitor and measure small changes in both electronic and acoustic response well beyond the level of our ear/brain analyzer. If this type of equipment does not detect significant change, but your ear/brain analyzer tells you there has been change, which do you believe? (Why is it important to have an IFR qualified pilot at the controls of an aircraft?)

As to the comment regarding a match between the 950/7xxx combo and Axiom speakers, there are many satisfied owners of this teaming. That doesn’t guarantee everyone will be satisfied, but the detractors are very few.

Again, I must ask, why does "break-in" always result in an improvement - how come the change is always for the better? This defies all logic. Heck, we're not talking aboug a pair of shoes here. I have never heard of someone who claimed to hear "break in" resuling in a degredation of performance.

Actually I have had a couple of experiences with equipment that I liked at first but got bored with over time. Don't know if it was because of break in or not.

I must agree with SH.
While new speakers can often have significant "break-in" periods, I believe that people are far more likely to have "ear/brain break-in" than solid state electronics.

I do have a related question however...
When turning on a cold solid state amp, how sigificant can the difference in sound be, as compared to a hot (warmed-up) amp?

In most cases, my ears and the amp start warming up at the same time, so it is often hard to tell how big the sound shift might be.

I believe that the optimal design operating temperature for most amps is probably on the hot side. Some amps are said to sing best when they are hot enough to fry eggs. Any thoughs or observations would be appreciated.

Allan

And more importantly, can our ears even hear the difference?

If you are worried about fatigue, you probably should have returned the Axioms, as they are known as being a little bright. Also, you may want to check out the September 2004 Stereophile magazine where Sam Tellig describes the sound of the Cambridge 640c as "a tad hard". Not to say the Cambridge is a bad player, because it certainly is not. Perhaps, you are putting equipment with the Outlaw pieces that are just a tad bright for your listening preferences. As a 950/755 owner, I can say that the Outlaw combo is very neutral and will generally only pass along what it is fed. Good luck with your hunt for audiophile nirvana!

S.

Exactly! Interesting word SirA uses to describe the Axiom, "revealing". I would have used bright. I had a pair of Axiom M80's and returned them during the 30 day trial period, they were just to bright. I went with the polk LSI series.

Solid state amplifiers do have a warm up period in which time the bias current in the output stage stabilizes. Usually this is controlled by a thermal feedback loop, and until the heatsinks reach a stable temperature, the bias may not be optimum. In some cases, this could lead to a lean bias situation which could cause more crossover distortion than the amp would otherwise exhibit. The effect would be much more audible with extremely sensitive speakers, like my 106dB/Watt horns than speakers with medium to low efficiency.

Tube amps reach operating temperature more rapidly because of the much higher bias current flowing though the output stage in comparison to a solid state amp, and the fact that tube amps do not have heatsinks which slow the warmup process.

i usually keep my b & k amp on all the time, will this cause problems down the road?will it shorten the life?

Not really, as long as it is in a well ventillated area. It is standard practice in professional studios to keep equipment powered up continuously, and I've never experienced any unusual wear.

i kinda figured it would be ok, but better to ask and be sure.
thanks SH

I've got racks full of solid state power amps that have seen all forms of "duty": everything from left on most of the time to being switched off and on once a day. Two of them date from the 70's - others from the 80's and 90's. I've never noticed a correlation between "mostly on" and "off and on" with respect to failure rates. In fact only one amp has ever failed. But after a $100 repair it's been back in service ever since. One other amp had two lights in each power meter that, one by one, eventually failed. When the last one went, I took the amp in to the shop to replace all four. At the time the tech identified a handful of parts (caps, resistors and transistors) than were out of tolerance. Again after a $100 bill everything was back up to spec. But you know I never did hear a difference in that 30 year old beast - and it's still powering my centre channel speakers (where I'd be most likely to notice.)

So as to turning 'em off and on or leaving them powered? I now turn mine off and on simply because eight stereo power amps tend to consume a bit too much power, even at idle, to be left on all of the time. Except for outright major failure, with the occasional bit of maintenance every decade or two, I expect my solid state amps to potentially outlive me.

And that leads me back to the original post for this thread, and the very cogent argument put forth by SH. If my amps actually "broke in" during their first few hours, or days, or even weeks, after being first turned on, then that process surely must have continued until, by now, decades later, they'd be producing nothing but pathetic bleeps and chirps. But since that's not the case, my conclusion is that break in is a myth in the case of such solid state devices.

I'd also consider that my speakers broke themselves in the first time they travelled a cycle or two. And my phono cartridge? Once around a groove would have been about it. After that they're all very slowly wearing out - not breaking in! But luckily for me I can't hear a difference. (Then again I've got audiograms of my hearing response going back to 1981 and it certainly has changed over the years. So even if I were to postulate that my speakers sound different now than when I got them in 1979, given the fairly significant change in my hearing, I doubt that any change attributable to the speakers over their lifetime would come within an order of magnitude within what's happened to my hearing.)

Jeff Mackwood

Not necessarily. If your amps actually broke in, they'd follow the 3 rules of break-in:

1) Break-in always results in a change in sound (always for the better, never for the worse).

2) Break-in automatically stops (but it does so only when the sound is optimal to your ears).

3) Break-in never goes too far (e.g., an amp will never go from too harsh to just right to too mellow). See #2.

As you can see, the very nature of break-in wouldn't allow your amps to reach a point where they produce "pathetic bleeps and chirps".

who's rules are these?

They're rules of audiophilia, which operate outside the laws of physics. They may make the break-in phenomenon seem suspiciously like the user is simply getting used to the sound of a new component, but that's just a coincedence.

I used to find arguements about break-in interesting. However, the arguements usually take on the feel of a discussion about religion (from both sides) rather than a discussion about a hobby one enjoys.

I am willing to accept that someone may or may not hear a break-in in any component in their audio system. Why? 1.) As a scientist I know that our knowledge at any given time is only a partial representation of the truth. Hopefully, our understanding of the world around us (and our ability to quantify it) continues to improve. 2.) We now routinely measure things in audio which were not even considered important 20 years ago (i.e. CD playback and jitter) 3.) At least my enjoyment of audio and HT is not purely a scientific endeavor.

Again, as a very wise man once said, "Not everything that can be counted counts, and not everything that counts can be counted." - Albert Einstein.

Actually, that is not really true. There are really no measurements that would apply to things like "break-in" on audio equipment that we have now that we didn't have at least 50 years ago.

Things like jitter measurments used on digital audio equipment have existed for decades, but have just been applied to other areas of electronics. The jitter measuement wasn't invented just for measurement of CD systems.

The mechanisms of change in the characterisitcs of circuitry over time have been known almost since the beginning, and solutions found for cancelling them - if they were'nt, reliable electronics could not possibly exist as they do today. Just think how unreliable things like aircraft would be if the electronics constantly underwent "break-in", changing their characteristics at the whim of the magical silicon's mood.

Another fact that that is not mentioned and often misunderstood about modern solid state electronics is that it uses, almost without exception, massive (and I do mean massive) amounts of both local and global negative feedback. One effect of negative feedback is to cancel any changes in the circuit's characteristics. The result is a stable and rock steady circuit, which does not change over time (i.e. "break in").

This is not true of some vacuum tube circuits such as my single ended triode amplifiers, which do not make use of global negative feedback, but only small doses of local negative feedback. In circuits like these, the characterisitcs and sound of the circuit are at the whim of the aging of the emmissive coatings on the cathode of the vacuum tubes. However even given this, any actual change in the sound of these amps is so gradual and subtle that I cartainly cannot hear it. Obviously, this does not apply to solid state electronics at all.

No, certaian fields are vastly more understood than other areas of science. You can't compare the understanding of one science to another directly.

Audio electronics is vastly simpler than other areas. Things liks analog to digital conversion existed long before digital audio did. There are'nt any magical mechanisms going on just because the electrons represent music.

i totally agree with soundhound (sigh) that there is no "break-in" period with solid state electronics.

things like speakers do change slightly with time though due to their movement.

the only kind of break you will experience with solid state is broken.

See, that makes you exactly like me, which I'm sure is a never ending source of annoyance to you.

Fortunately, the reverse is not true.

I understand that jitter measurements were available long before the CD player became common place. The point is that no one at that time (the big-hair 80's) considered digital jitter to be important so it was not measured. It took a minor paradigm shift to get beyond the "perfect sound forever" mythos.

My point is simply that I have no doubt that there are many things, even in a simple field like electronics, that we do not understand completely. If our understanding of electronics is complete and cannot be improved, then our universities are wasting a lot of time. money and effort in their engineering programs. In an audio system where you have complex interactions among the source material, electronics, transducers (animate and inanimate) and the environment the probability of unmeasured effects seems more than likely. There are certain basic aspects of all science that transcends disciplines and one of those is that the knowledge in the field is always imperfect unless we assume that we have all the knowledge in that field that exists. No scientific endeavor today has, or claims to have, perfect knowledge.

Also note that I never said I believe in break-in for non-mechanical components as an important phenomenon. I simply refuse to dismiss it out of hand and can accept the fact that some people hear a break-in. Whether it is the system or the user breaking-in remains, in my mind, to be seen.

Hmmm .... is this a good thing SH?

How would you explain the fact that audio circuits seem to be the only ones that "break in" compared to other industrial equipment? Are audio electrons really all that special? It's easy to throw an opinion out there on a subject, but I wish you would back up your position with some technical facts from direct experience.

Note that I am specifically not talking about electromechanical equipment like speakers, phono cartridges, microphones etc. Things that involve moving parts always wear for better or worse.

Again, I never said I believe or have experienced break-in of non-mechanical devices, so I do not see what facts you want. The fact that break-in has not been found in other electronics may mean that it does not exist but depends on whether it has been looked for. If you do not admit that something is possible then it will not be examined.

I am simply not so rigid or presumptuous to believe that we have total knowledge in the field of either electronics or audio electronics. Therefore, I am willing to entertain the possibility of break-in (or change over time) of electronic components. This is not the same as "believing" in break-in since that would require an act of faith, not science.

If you feel confident in dismissing break-in of electronic components based upon your knowledge and experience, then I respect that. I also expect the same courtesy from others.

Again, let me be clear. I AM NOT ADVOCATING A POSITION THAT BREAK-IN OF NON-MECHANICAL DEVICES OCCURS OR DOES NOT OCCUR. I AM SIMPLY MAINTAINING AN OPEN MIND ON THE SUBJECT.

A routine phase in design in any electronic system is to be aware of the areas that can cause drift due to tolerances, heat, time or other effects, and design around them. It is standard practice in any field to compensate for possible variables, your's included I would imagine. Geez...

Just a question about the discussion. SH, when you refer to "Industrial Equipment" what equipment specifically are you referring to? My first thought here is....maybe one doesn't critically listen to/evaluate "industrial equipment" so maybe subtle changes (break in?) wouldn't really be relavant or examined. Certainly in Audio, when we are all sitting in the quietness of our houses, listening rooms, studio's etc ..subtle changes might be noticed? Certainly not challenging the premise, just trying to understand all the points of view,

I am one of the loony audio geeks that swear I can hear a differnce in electronics as they age...for whatever reason.....and not always for the better. I'm sure it's my ears that deceive me....THOSE HAIRY BASTARDS!

Peace,

S

Actually not. As a scientist my goal is to seek understanding of variables and systems. It is then the goal of engineers to use that knowledge in design applications. Whether certain variables can be compensated for in actuality may depend more on factors such as economics or aesthetics than science. However, that seems a little off topic. It seems that much of our disagreement is about the philiosophy of science itself and the role of paradigm shifts and new ways of looking at the world in science.

FYI, my particular field is quite aways from audio electronics. I am an ecological geneticist and also teach biostatistics.

It is a catch all that includes anything not related to audio. One of the types of electronics I have designed was test equipment that tested audio circuitry (at Altec Lansing). This type of circuitry obviously must be a stable as possible, yet it uses the many of the same types of circuits and parts as the audio equipment in the home. Knowing what types of parts and circuits are subject to changes and which aren't is very important in this types of design, and knowing what to do about it.

Yes......and they do compensate. Truthfully, audio is such a basic (and old) type of disipline that it is very simple and a matter of course that potential problems from drift would be compensated for. No magic here. Maybe in very advanced circuitry well beyond the scope of audio using technologies that haven't been around for decades, but not audio. You can argue "what-if's" forever, but at some point reality sets in.

The disagreement is not on some theoretical or academic level - it is on boring 'ol rubber-meets-the-road practical engineering that is routinely performed, day in and day out. Your field is a bit far removed from designing audio equipment, and it is probably less mature, more complex and less well understood.

i think this topic has exhausted all interest on "break-in".

Who asked you? Go back to your room.

I agree completely.

Well said and I also agree completely :p

I'm not sure if it's theoretically possible, but the explanation I've heard from at least one high-end audio company is that their components need some time to break in because it takes time for all of the capacitors to fully charge. This at least seems scientifically explainable. Not sure if capacitors can, themselves, break in (have a higher total capacity after some amount of charging and discharging), but such action might explain an audible effect.

Not an engineer by a long shot--I'm just throwing a theory out there.

The capacitors charging would be part of the warm-up process, not really break-in, as they will charge up every time you turn the unit on or plug it in.

Capacitors that are in the audio path (as opposed to the power supply filter capacitors) can definitely change the sound of a component as they age over time, especially if they have a DC voltage across them as in a blocking capacitor. The problem is that capacitors have not really been used in this way since the widespread use of integrated circuits rather than discrete transistors - in other words at least since the 1970s. Vacuum tube circuits use blocking capacitors which may have hundreds of volts DC across them, and these capacitors can certainly influence the sound. In discrete transistor circuits that use blocking capacitors the DC voltages are much lower, but the capacitors still will change their characteristics over time.

In my tube amplifiers I use this aging effect to in effect "tune" the sound character of the amplifier to match the characteristics of the speakers. The use of oil capacitors in the circuit path is widespread in tube amps as a way to achieve this.

I would certainly say that components manufactured in the 1950s and 60s changed their sound from the time they were new, apart from the aging of vacuum tubes. Whether this would qualify as "break-in" is a matter of perspective.

So far this topic has been primarily focused on the equipment. I wish someone with expertise in human hearing and brain processing would chime in. Take for example, our sense of taste. We can take something disgusting such as the very first drag on a cigarette and over time have a love and a preference of one brand over another. Same thing with alcoholic beverages. So why not hearing? The first few days we don't care for how our system sounds but then it begings to sound better. Equipment VS brain processing. Anyone out their with medical or psych info on this?

That is the arugment I've been trying to put forth from the beginning, that it is really a case of the listener getting used to the sound of a new piece of equipmet over time and as a result it sounds better to them, thus "breaking-in" of the ears rather than the equipment.

I run into this all the time in tuning systems with EQ, and it's a bias that I have to fight. Over time, even a "wrong" tuning starts to sound "correct" to my ear as I get used to the sound. If not realized and fought, objectivity is compromised. The same is true of mixes of music I've performed - any mixing job starts to sound "right" after a while, no matter how it originally sounded.

New pieces of gear that have run through my studio (new equipment I bought for my film work or equipment designed by one of my best friends, who is a designer of audio equipment for some high end brands) at first listening sometimes sounds startlingly "different", and over the hours/days, they start to sound like the "norm" rather than "different".

In these instances, I have cross-checked the differences in sound both initialy and over time by using two examples of the particular piece of equipment. I use one only of them (usually because I only need one of them) and do not power up the other piece at all (in some instances, I've known that both examples are completely new since I've assembled them). After my ears have adapted to the first piece of equipment (what some people would believe as "break-in") I have performed an A/B blind comparison of the original piece of equipment to the absolutely new piece of equipment.

The result has always been the same - the used piece of equipment and the never-powered-on piece of equipment sound identical.