Noams, to be perfectly frank, I'm not sure I agree with any of this, as I already said:
"Personally I think using the sweep tracks on a record like the Cardas regularly keeps everything (including the cartridge!) in shape."
HOWEVER, one does need to run a signal thru the equipment and cables to "break them in" if indeed "break-in" is even a real world phenomenon. That's because at "idle" (no signal) there is no current through most parts of the circuits, so all the little internal components and wiring are under zero stress.
I have kept an eye (ear?) out for "break in" changes in all parts of my systems for over 40 years, and have used all manner of break in accessories and devices (except for an AudioDharma Cable Cooker.) Personally, the only "break in" changes I've experienced over all that time fall into a few specific categories:
1.) Cartridges: ALL new cartridges ALWAYS go through a break-in period. Well Duh! If you flex a new piece of rubber long enough, it's going to relax a little bit! And of course there's those tiny little coil wires with their enameled insulation that will be altered at a molecular level after carrying all that electromagnetically induced current ;--)
2.) Cables: Well, first of all, the last time I bought any kind of new cable was around 1990 when I was rich and bought some Straightwire Maestro spkr and IC, and 3 pair of Magnan Type Vi. Some stock PCs had IEC connectors back then, but nobody made aftermarket PCs, so that issue was moot. A set of vdHul tonearm cables came w/ my SME V and I used those until three years ago (for 13 years!) until someone at Sumiko (SME US rep) told me in language I won't repeat here, that they sucked and I should consider Cardas Golden Reference; right after that I fell into a pair of Purist Venustas which blew my mind -- but I digress....... Back then, the only "break in" anybody discussed was their automobile engines and their shoes! Since then, I've bought almost all my cables used, so when "break in" became a hot topic, I had no way to tell if my cables were changing or not because all mine were presumably already broken in!
3.) Equipment/components: What I said about cables somewhat applies here also in my case (used purchases) however, SS equipment has not appeared to change much from its out-of-the-box sound. Tube equipment does change -- a lot! But that's due to the tubes having to burn in, not the equipment itself. And once burned in, tubes, like cartridges remain the same until shortly before death!
4.) Speakers: a qualified "always" as in: "it's ALWAYS something!" But is it the crossover and wiring, the electrostatic membrane, the woofer surround, the voice coil? All of the above? Probably, but will you hear changes? That would be a definite "maybe" depending on the individual product. Stats definitely smooth out, but is it the membrane or the electronics? And do speakers benefit from occasional conditioning with frequency sweep CDs? And if I could hear a difference, how would I know if it was the speaker that had improved, or something else further upstream -- after all, the CD affects everything from the transport on out.
Bottom line? Well two things:
The biggest break-in changes I've heard over and over again are with cartridges and tubes.
The biggest maintenance improvements I've heard over and over again are, first and foremost, cleaning plugs and connectors. And a less obvious second, using the Cardas record (for cartridge de-gaussing) or the Purist CD (for system conditioning.)
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