breaking in audio components

I worked in the electronic component manufacturing field for 10 years making ceramic capacitors. I can tell you capacitors change value over time and the change is logarithmic - so the largest change is when the component is "new". Some of the high end military contracts required burn-in for each individual component before we shipped them. This was to insure the component value was sound and therefore the circuit it was in was far less likely to fail due to changes in capacitance value. It's nice when you are shooting missiles if they don’t fail. The change in value had to do with how the material changed electrically (capacitance increase or decrease) as electricity was applied to it. After a certain amount of time - the change was negligible. I could go on an on and boar you to tears but I can tell you burn in is legitimate ... if you don’t believe me check out AVX, Kemet, Vitrimon, Kyocera web sites ... they have tons and tons of engineering data for circuit designers. You will want to look at life test data sheets. They might be a little hard to discern if you don’t have a lot of experience reading them but you will notice they are on a logarithmic scale.

You look at how the dielectric changes over time and the design your circuit accordingly. That’s probably why the sound improves significantly over a short time and less as time goes on – the person that designed your linestage calculated it that way. I don’t think I’m going out too far out on a line to assume most conductive materials change electrically in some way over time. If you can calculate this rate – you can design around it.

Any Material Science or Ceramic Engineers out there? Chime in now please …

The Horse

gentlemen, the point of this thread is to determine audibly if possible, what are the signs that a component has "broken in" sufficiently, so as to make a judgment as to whether you like it or not and/or wish to purchase it or not ?

are there any aspects of frequency response or soundstaging that one might listen for to be confident that much or most of the break in has already occurred ?

if your dealer doesn't know what the break-in time is, he's not a very good dealer!
p.s. count me in the "believes break-in is real" group

Sometimes a dealership will loan out a demo which is probably the same one loaned for other customers & no doubt already broken in. I would then have to agree with Musicslug, that an informed dealership should know his products and the required break-in period. Aside from new component break in I know that my system always improves after an hour warmup.

I'd have to side with people saying they DO notice differences after break in. And with components, speakers, and cables (IC's, speaker, and PC's). Granted, some are more subtle changes, but some are more noticeable (in this hobby of "splitting hairs"). Probably the only things in my system I don't notice "breaking in", are the isolation tweaks I've used.