The sound is coming through day-by-day with my new cans. I'm leaving them on a loop with Isotek break-in audio and it seems to be working.
I was just suprised my 10x cheaper superlux cans sounded way better (warmer tone, timber,more musical) than the 400's but I was sure it was the lack of break-in with all the raving reviews these get.
Does anyone know why pigskin is not chosen for leather earpads vs lambskin and cowskin ?
Is it too sweat absorbent or oily ?
A warmer tonality is typically easier to like than one that is a bit cooler. Doesn't mean one is technically better than the other though, as there are so many other factors involved (extension, detail extraction, separation, staging, clarity, to name a few)
It is obvious you favour a warmer tonal balance, so my suggestion is become more acquainted with your new cans' sound signature, and then decide of its benefits outweigh its cons specifically for your personal preference.
Sorry to break it to ya, "break-in audio" won't do much at least on the macro scale (warmth for instance).