I made some earpads with a smaller inside opening (new left, old right)
Pretty much did as expected. Substantially shrank the sound stage, while improving the sound quality (but not magnitude) of the bass and being a fair bit darker of a sound.
Overall, I substantially like the old earpads better. They offer a much more believable image and are overall way more enjoyable to listen to. The only artist that sounds better on the new ones is 2Pac.