Another question, i'm on fire tonight, but what about speaker break in, does it really happen? or do we just get used to the sound and our brain filters out the things we didn't like? The same goes for amps and cd players? do the really burn in?

Speakers, most definitely IME.

Over time, the cone suspensions become more responsive, allowing for a more 'mellow' sound.

Not so sure about amplifiers and CD players.

In theory, electronic circuits are supposed to be absolutely stable ( when designed properly), but in practice, there may be variations due to operating temperature, internal component life span ( electrolytics in particular tend to slowly alter their behaviour, but also some - but not all - resistors due to cold / hot conditions they operate).

Nothing stays the same, forever methinks.

I was very sceptical about device burn-in, until I ran into a brand new Marantz CD player. As is, straight out of the box, my first impression was that this can't be the device people were raving about at the time, too harsh, it screams at you, etc.

96 hours later, after it had been running for 4 days and nights into a dummy 10K load, it was a completely different device. I found it hard to believe it was even the same one, from the same company. Totally different! Sweet, mellow, with much definition and detail, it became perfectly clear why people raved about it.

Don't ask me for an explanation, frankly, I have no idea. I can't find any logic in it, but since it happened to me, I can't deny that there was not just a difference, there was a hell of a lot of difference. The only thing that comes to mind is that the capacitors were obviously not formed previous to installing inside, quite understandable for a large company.

When made, a capacitor is not really polarized, just tentatively so. It needs a bit of time to setlle down to what it should be. I form them previous to installing, which is s simple process of first charging a brand new capacitor with 5V, then discharging it with a resistor, then charging again at 10V, discharging and lastly charging with 15V. The process is intended to give them three full cycles, thus forming them to their factory specs. It is better than just installing because you can discharge them completely with a resistor to a point they probably would never be inside a circuit, because of loose eddy currents.

Also, going in steps allows for a slower, but very thorough forming. I will gladly guarantee that such capacitors will last at least 50% longer than non-formed installed straight in, and this is the reason why I do it - improved reliability and service life. Of course, I don't do it one by one, I take a couple and do say three by three.

I think its an over used and abused modern word used for making excuses, I think some products need running in but not to the extent its all played on in this day an age.

I get a bit feed up to read that it sounds Ok but once it's burnt in i'm expecting it to sound much better, this reads to me as excuses that the product isn't really that good in the first place and fingers crossed it might get better a bit latter.

I find more to be true is warm up, once something is warmed up, lets say 20 minutes to warm up and settle down and stabilise then that is it, none of this if you turn it of it needs another week to opitimise its performance again, a load of rubbish I think.

Like Arthur I'm more inclined to think speakers may need burn in, even then I'm not 100%, I think room temperature will more of an effect than burn in. Whats burns in? the drivers or the crossover? I think one the driver has moved back and forth a couple of times that should be it.

As for cables burning in, well, lets say I've never heard it.

Speakers are transducers, meaning that they turn one form of energy (electrical) to another (mechanical).

As with any other mechanical device, they do have their burn-in time. A modern car engine won't give you its very best before it's done about 30.000 km.

I've got to agree with dvv on this most recently due to my experience with cyrus amps.
The instructions included even state this.
The amp changed from a slight harshness to a much nicer sound after a week or so and it seemed to find a lot more bass output too.
It's cables where I have my doubts about burning in.
Cartridges and speakers are a given though..they realy do change after a week or two.

I can't recall it was soooo long ago

Without discounting the (possible) changes in component electrical behaviour, could there be something else at work here as well, psychoacoustics perhaps?

Could it be that our ears / brain, after a short period of time, start a process of adjustment from what they ( ears / brain ), were subjected to, before the new components arrived?

I am certain, if this issue was to become the subject of a scientific study, most of us would be surprised at it's findings.

Do they really adjust? and by such a large extent?

For example, your room acoustics are poor, bass booms, treble is bright, if you was to continue listening in that room over a period of time would your ears compensate and would your brain adjust to the poor sound?

I think not. On a few occasions I've heard changes, the Kudos C30 changed quite a bit, so did the AstinTrew AT3500, but I've never experienced it with cables, they always sounded the same from when I first plugged them in.

If a sound is bad to our ears it will still bad, I'm a bit wary of reviews that say something to the effect of that when the reviewer first heard it it was unlistenable, but the next day it was one of the best things he'd ever heard, like Arthur I'd like some proof of this as it is quite a radical claim to make.

But not many people have gone to the trouble of testing these so called burned in units to brand new units, I'd like to see a bit research done about this rather grey area, funnily all manufactures do tend to claim it though.

@Arthur
Absolutely! Compulsory instrumentation is a mug of cold beer.

@Adam
Agreed in general, but having experienced the Marantz situation, I do have a small reserve. If asked beforehand, I would have said not possible, but after that, I say not very likely, but not impossible.

Obviously, if that slim but real possibility is misused, it does become meaningless, much like the word "ultimate". By now, even my toilet seat is the ultimate in ceramics.

Writers in audio are really simply reflecting the sales blurb we see all too often. We see an ad which is aimed at telling us that this is the real thing, everything up to it is junk, but now we are saved because here it is, the ultimate in its price slot, blah, blah, blah. Writers are people like everybody else, they can't help being influenced by what they are surrounded with. So, like us, they are stunned when they take out of the box the latest "ultimate" device, only to hear some mediocre sounds emanating from it. Our ears do adjust up to a point, I have no doubt of that, but I also expect the writer to both know that as well, and to take that into account when passing judgement. Whether they do, and if so, to what extent and how precisely, I have no way of knowing.

So I look at it simply. I flip through a magazine, say Alan's Hi-Fi Choice (which I have been reading like forever, I always took it as a reasonable middle-of-the-road mag, both subjective and objective just about the way I like it) which is the mag I am most likely to pick up anyway. First I look over the table of contents, to see what's featured in that particular issue. First filter, I discard what I am not particularly interested in and leave it for later times. Next, I look over the authors. If I see Name No.1, I immediately discard the text because I have a personal beef with the man and know for a fact he's not half as competent as he would have us believe because he allows no other view than his, and never mind if he knows very little on the matter. If I see Name No.2, immediate relegation to the junk pile for good, the man's a transatlantic w. If I see Alvin Gold, check, read that, experience teaches me we have very similar tastes. If I see Paul Messenger, check, read that, never let me down once so far, and it's been many a year. If I see Paul Miller, drop everything and shortcut there at once, run mode. Etc, leave Alan's column for last, like a good beer after a good meal. All very personal, of course.

The point is, we all have to make up our own minds who do we wish to trust. I would like to be shown any bombastic statement like bad in the morning, fabulous in the evening in any comment of the people mentioned above. No, these guys are mostly old guard, well versed all around, they don't think or speak in leaps and bounds, they are methodical and oh so very experienced. These are things I can relate to, and these are the things I have learnt over the years to trust. And it has served me well.

It's the up-and-at-'em younger fellows I have yet to sift through, though I must say Jason Kennedy sits well with me, comes across as a reasonable man.

(@Alan - as you see, I believe in good balance. Just as I am quick to criticize the audio mags, in all fairnes, I am also obliged to give credit where credit is due, and thank God, there are people I am only too happy to give fair credit to, they have earned it fair and square).

It must be a highly confusing job being a reviewer because they get to hear so many different products just how on earth are they expected to recall how each one sounded then try to compare, then to make matters worse they have to detect if the product has changed sound due to burn in? For us as individuals it may be easier to make note of a change in sound from when we bought something new to how it sounds a few weeks later, but for a reviewer to pick up on such things is so much harder to believe.

What about the thought that once something has be broken in, if you leave it for a certain period of time it will then return to its original state. What's all that about?