I’ve had ‘further burn in’ due to using different ‘area’ of kit/some chips needed ‘more time to settle’ to find their penultimate sound state. (Last state being ‘worn’ and needing replacement or servicing to sound great again…)
so “worn in” vs “worn out”?
yes… along the way in burning-in a Naim Nait amplifier, around 600 hours of on time (and varying low volume level music mostly) sounded fantastic.
When I first used the headphone amp ot was obvious aspects of that needed breaking in (logical), but…
the amp benefitted from further use at higher volume.
A real eye opener was during burn in/‘break in’ that 40 hours+ of time above 0930 on the volume dial really helped the flow.
Certainly wasn’t speakers or cables or elsewhere in the system, and a ‘grain in the sound’ I typically hear only in new bits of kit which usually goes away quickly, which was in higher volume music, albeit ‘quite subtle’, took a couple if days to work itself out and this was nearly 1000 hours of on time.
What I had experienced, that I may not have described well here, was certainly ‘further alterration of the sound’ traits many many hundreds of hours use later, and only changed when I ‘started using’ those parts.
That being said -I take component ’ break in seriously’; as an example- going so far as to feed an A&K DAP with a tube preout; where it only engages both tubes in balanced output mode- and using the balanced output mode to feed into a Grace m903 simply to cook/‘burn in’ both those tubes equally.
Using that DAP in tube mode can disable 2 of the 4 DAC chips (best ‘natural sound’ by a large margin), but refeeding that signal into the remaining DACs allows a Hybrid sound mode (next best sounding mode, arguably, if chasing natural audio), and finally, bypassing the Tubes, equals a 4x DAC chip mode with Opamp output stage exclusively. (sounds great for Dance and electronica)
-So many ways to ‘burn this device in’ where differing parts are all on their own timetables. (and it sounded like that).
Not wanting to have one valve heavily used and one ‘untouched’, I had to avoid single ended output modes, and ended up putting a balanced cable on my in ear monitors to ensure ‘full circuit’ being used internally.
The extra 2 DAC chips will probably still have their grain intact when the valve preamp is no longer usable! although I have since gone to effort to ‘cook them’ when I’m not using the player, after seeing the Naim amplifier ‘continue to settle’, months later, as parts inside weren’t being fully used
Electrons settle over time, and like water cutting through rock, find their easiest/‘shortest’ path.
Even on a power lead, there is a settling effect. (that is lost after a couple of weeks of no signal enforcing the pathway)
Cryogenically treated cables I think avoid this resettling process,. and hence would be my goto headphone cable tech to shortlist if I was recabling headphones I use infrequently…
I suppose decades of buying bucketloads of new and second hand kit, there are traits that I only see in new kit that quickly vanish, that I never experience with used kit (revealing it isn’t just ‘brain adjusting’ to sound)
So, I’ve learned to do break-in right. eg that Grace m903 headphone amp is often in MONO mode for equalling headphone driver usage during the first XXX amount of hours… (before I listen for any length of time).
so, whilst clearly I believe in the burn in effect as something to ‘get on the other side of’, many advocate “just use the kit as you intend to do” (and give it time/enjoy)