Do electronic components "break in"?
 

Do things like decks and amps "break in"? that is, do they sound better after you play them for X number of hours.

I think it does take time for the deck/amp to sound its best, or at least to its optimal working temperature, but the difference compared to speaker break in is minimal. Normally you will notice bigger difference from speaker break in that is. I would say don't worry about it.

Short answer is no, it won't sound any different after you break in an amp or deck.
You may notice a break in smell the first time it gets hot, but that is normal.

mmmmmm break in smell

Transistor electronics take seconds to thermally stabilize. However, there is some tool on ECA claiming that they need about 4 hours to do so...

Tubes need a few minutes usually.

In terms of break in over time I can't see how they could change enough for your to hear, and it wouldn't necissarily be "better" even if you could.

I disagree with the times quoted by you and the other guy on ECA, it will vary depending on circuit board design/ layout and mounting so any quote should be considered relative to the equipment and environment. Tubes will take a minimum of 3-15 minutes every time and maybe a couple hours the first time it is turned on (Conrad Johnson lesson learned), and transistor based systems can also take a while to warm up but generally less than 5 minutes for most car stuff (cold weather could affect this I suppose).

The term you should be using for this is isothermal and the value of everything from capacitors to inductors to resistors will vary with temperature. The transistors operation will vary fairy significantly with temperature, they tend to conduct more current at higher temperatures.

I have heard the 'break in' of equipment but nothing really profound other than the Conrad Johnson preamp which was perhaps the absolute worst sounding piece of equipment I have ever heard for the first 2 hours of its existence. Then it just sounded like a typical CJ.

There was a design flaw in a big name amp a few years back and the amp would make some very strange sounds as it warmed up and sometimes after it was warmed up. Several I heard had a horrible HF whine from the amp once it was warmed up... unacceptable... I am glad I never purchased that product.

I would also say 'dont worry about it', this should not be all that significant in a properly functioning product

Thanks for the replies and explanation guys.

Sigh, I was hoping my deck would be even _more_ sweet sounding :)

As far as a 'break in'.. any physical change in new components will take place the first time they see power... its also true that semiconductors and caps will degrade over time due to BOTH heat and applied voltage (changing one alone or both together can effect a physical change) But devices and tolerences are selected to a level where any gradual change will still be neglagable...

an example where you may see this with a semiconductor and it matters, is a computer CPU that looses stability over time... (most common in cpus that have had thier core voltage boosted and are overclocked)


I don't want to pick on you, but you should read the definition of isothermal...
isothermal - Definitions from Dictionary.com

Id agree that there will be measurable differences in the components inside an amp from when its cold to when its hot... inductance of caps goes up and capacitance can go up or down depending on the type of cap... a semiconductor's resistance will go up or down, also depending on the type of semiconductor... ect ect

But I'd also bet my entire car stereo system that any change in the output of an amplifier is not going to be audible...

iso (single) thermal ... my point was there is a variation in performance till isothermal conditions are achieved then they should be constant. My terminology is correct, the warm up is the thermal transient, I did not present the information as well as I could have.
edit: Me no use word good

lol me no so good with words some day either.... and I understand what you are saying...

heat exchange = not isothermal unless you are at a steady state equillibrium...

Very interesting opinion...learned something everyday.

ahh yes ... but the circuits are at a constant temp (though individual components will be at different but stable temperatures) so its electric characteristics should be stable. heat in= heat out (that is why it takes more than a few seconds to get warm). I think we are agreeing that a lot of angels can dance on the head of a pin...

to the room the amp is a heat source
and the room is a heat sink to the amp

aint thermodynamics grand

I hated thermodynamics - my prof was a moron.

Good thing I'm really fricking smart or I would have been done for :D

If you put it like that you would be right, so long as the room is an open system...

But if you want to break it down... consider that the thermal time constant of a component like a mosfet is going to be short compared to the dynamic nature of music (range would be like .1 to .5 seconds).... that basically tells you right there that there is no way you will find a steady state thermal equilibrium inside the device while pumping music through an amplifier.. the temperature of the fet will jump around with the signal, and there is no way isothermal conditions could be met...

If you played a test tone that lasted for a long time in relation to the time constant of the heat sink with the other condition above met then yea you could consider the fets to be running under isothermal conditions...


all that aside so we are on the same page, I think the really important point is that an amps temperature is not going to make an audible difference....:laugh:

You won't even notice the difference if it does.

_____________________
McIntosh MC207 Power Amplifier - Get the MC207 Power Amplifier catalog by McIntosh Laboratory, Inc.

Warm up
 

I seem to recall several test reports on various amplifiers, noting that performance improved after a significant warm up period at moderate loud levels.
There is a venerable line of 2 ch. British Home Audio that I carry, and their amplifiers come with a notice to the consumer stating that, the unit they purchased, will require 36 hrs. of "break in period" for optimum performance.

Maybe "Mythbusters" should take this one on.

^ yea I think so... :retard:

True dat. My worst course.