Burn/Break-in

OK, contensious but I have a few questions :

You regulary hear that burn/break-in is required for any new components. I've read in several manufactures literature that the performance [of said component] will vary throughout the burn/break in process.

I'm currently running-in a new pair of speakers and have noticed this effect in both the upper range and low end . As these are a mechanically based component with moving parts, I am less sceptical about the issue of running/burning/breaking-in, but has anybody had this experince with non-moving parts and their fluctuating performace during initial use ?

 

yep

stuck some new rubycon caps in my valve phono stage a few weeks back (thanks WM for suggesting them)
At first all was muffled, then no bass and then muffled again, now all hunky dory.
The only parts i found not to need burn/run in (DIY parts i mean) have been resistors

 

Must say I've only ever noticed speakers running in, not electronics. IME speakers get bright and shouty after a few hours' use which I always attribute to the tweeter loosening up first - they're then rather bass-light for the next 30-odd hours' use and start to warm up properly after that.

 

I've personally never heard any difference in components with no moving parts, so I regard this as yet another myth - but then I would, wouldn't I?

 

Naim stuff takes a day or two to get going properly. Brand-new speakers need a bit longer.

 

i remember hi-fi plush did a test on this. they took a pair of b&w cdm1nt's and stuck them both in the same room (so no temperature differences between them). then ran 1 constantly for some time whilst the other was left unconnected. when they measured the most obvious parameters there was little or no difference (can't remember exactly what they measured except 1 was a waterfall plot which showed how quickly the speaker cone stops moving across the frequency range).
i believe that 'running in' as it is accepted stops after at most a week after that it's the listener accepting the sound of the new equipment. either way from my experience it's a real phenomena however whether it's a physical process, a mental one or somewhere in between i don;t know.
cheers


julian

 

Me too. I relpaced some NACA5 so that I could run it under the floorboards. For the first couple of hours it sounded a little screechy, then it improved for a couple of days, then it had a few days sounding slightly duller, and then it settled down and sounded as good as the old run.

 

I found that both the Nait 5 (now being sold) and the CD5i both went through a 1 month burn in cycle.
Initially, they both sounded veiled, then lost the veil and became rather "screechy", before settling down to sound pretty lovely.

The neodymium tweeters that I replaced on my Kabers also took a couple of weeks to burn in.

 

Another topic that the ' bollox squad' love to dump on
The Shearwaters & the GR 20's to a sodding life time to come on song (8 weeks min), but it is more than worth it.
Also Clock mods & psu's I find do this as well, along with cap replacements, os-cons in particular are culprits at this. Wm

 

Could someone explain what happens to the components when they burn/break in.
I am particularly interested in what happens to solid state components and cables.

 

Thanks, Stebbo, I await this one with interest...

 

A fair question!
I can happily understand that components may reach an optimum operating temperature, but that would not take days/weeks. So beyond that i have no idea and couldnt even guess at an explaination.
And yet i have heard it in practice - beats me

 

Easy. They sorta 'burn' or, kinda like, break in. In other words, at first they 'were not burned in'. But then they 'are burned in'. Dig?

 

Interesting that this topic is brought up by someone called "voodoo".

In speakers I can imagine the materials surrounding the cone need some time to loosen up. In electronics however I am much more sceptical. I have never seen any decent explanation by an expert in electronics. Not to offend anyone, but I like to think of it as a psychological phenomenon. But saying this to audiophiles who trust their ears usually ends in a fruitless discussion. People bashing eachothers choice of equipment or sense of hearing, that sort of stuff. I don't say that people who believe these things exist are lyers. I believe they really hear it, but the mind plays interesting tricks on people and getting used to a certain sound is a well known phenomenon when listening to someone else's kit, which is of course allready burnt in. Could not the same effect cause the impression that gear changes its sound, in the first few weeks of listening to it?

 

Yes, I think reports (currently rife on the Naim side) about equipment, cables, and, believe it or not, mains spurs "burning in" over weeks to months, are fanciful to say the very least.

 

He, He I thought you 2 would come out of the woodwork , now as Penance says, Its a valid and fair question?, do I have the Definitive answer, Oh coarse not, I have 'Ideas & theories' "Ranson's" if you like, Myself I'm particularly interested in Stuarts 'torpedo's' he's going to use to try & scuttle me with
Ok, I'm going to use 2 examples (electronics, that I truely believe & can hear) do 'Burn in' (change sonic characteristics over a period of time) Capacitors and transformers.
As you know I Mod a lot of cdp's & amps, and by careful section of capacitor types, be it Electrolitic/foil/film/paper in oil, I can 'tune/cahnge the sound' the component gives, same in speakers too.
OK, the top quality caps (electrolitics, Black gates/Os-con's) and to a lesser extent Rubycon Z series/Panasonic HC's,
When these caps are first installed, the sound can be 'thin & fleshed out', with a hazy presentation, this can changed to big full bass, and bugger all detail, (this is in the 'IN use condition' not at idle, caps take eternities to run in at idle ), with oscons' this can last for upto 300 hours (in use time), black gates maybe 50-100 hours, but the z series caps are also a long drawn out processes.
Now weather this is a change at the molecular level, or an a electrolitic process 'firming up' I cannot say, I haven't made an in depth study, But it is an accpeted fact with the a great many of the , manufacturers that running if (if you like) is accounted for.
Transformers, well, one up your street Tones, does the resultant magnetic field core densities, manipulate the Iron core's structure at the atomic level, or does the wire just mind meld with universe so it produces a 'happening thang man'
Seriously, when I'm building a custom psu, I run in my trannys , and if you take a fresh out the box version and compare to a 3 week run version, there is an audio difference in my experiance.
Ok boys fire away. Wm

 

Does it matter whether there is a scientific explanation or not? This is akin to double blind testing. If a goat stops me in the street and asks the way to the brewery, should i be questioning my own sanity, or instead be propelled to international stardom and reverence. Either way, to my knowledge, the goat found his way to the brewery and got well and truly pissed.

 

I dont want to go on and on about what people can and cant hear. Because with that we will be here for weeks posting back and forth.

I am interested in the physical changes that MUST occur for a change in sound to be noticed.

Cookiemonster has a valid point, "does it matter". Well in the context of my question, yes it does.

Because in this little ol' world of ours a change in sound will result from a change physically of the components that are involved with the production of the sound

 

Could the insertion of a new component affect the performance of the other/original connecting components ?

For example : If I change a speaker cable, will any differences be down to how the adjoining components see the new cable ?

The original cable carried the signal in a particular way and my speakers/amp are used to 'seeing' the cable in a particular way (impedance variations ect.). Is burn-in possibly as much to do with the other components reacting to the new cable and adjusting accordingly ?