After ~1 week off from the Yenona's (burning in & listening to my new Lyx Pro HS-30's), last night I listened intently to them for an hour. They now have MrSpeakers Alpha pads + 1-layer of lycra-type fabric placed inside the pads.
They sounded amazing. I had difficulty taking them off to shut down the home office.
I'd noticed previously that the Alpha pads slightly lowered the level of the bass (not a bad thing w/these bassy cans). More importantly, these pads pull up the midrange somewhat, such that the bass & midrange sound continuous & balanced. This was the most positive tonal change resulting from the switch to Alpha pads. I had added the fabric insert to tame some remaining, modest elevation of the upper midrange and treble, which it did.
Anyway, last night I noticed one not-so-good effect of the Alpha pads: they're so deep & inclined (1.5" on the deeper/back side & .75" on the shallow/front side) that the Yenona's aren't sealing well. They have very little clamping pressure to begin with--a nice quality that helps make them the most comfortable headphones I've ever used--but with the Alpha pads, this means the very large/deep pads sit in a "cocked" position against the ears & don't seal well: what little clamping pressure there is affects the front of earpads, and the back/deeper side of each resting more loosely against the back of the ear.
What I did was lightly press each index finger against the outside of each earcup, and the sound "locked in" quite noticeably. The bass became more impactful and the soundstage (another good quality of the Yenona's IMO) widened a bit more. Pretty silly to sit there for an hour w/a finger pressing the outside of each earcup, but I gladly did--the sound was so good that way...
I may switch the Alpha pads for HM5 "extra thick" pads, 2 more pairs of which are on order. I'm curious to hear what this sounds like, based on comments of
@peter123 and
@Lurk650.
Regardless, I've already established to my satisfaction that the Yenona's sound is malleable & relatively easy to modify. Still loving these inexpensive headphones!