Do 650 pads fit the 600? The yaxi pads are originally for the 650.I used Alcantara(Yaxi), cow leather(Zmf) and sheeps/lamb leather (Zmf), but only on the darker/less neutral 650.

The Yaxi's were the closest to original. It does add a bit of bass but the rest of the spectrum sounded reasonably like the original sound. The different material will never quite sound the same but this was close enough for me and a lot closer than leather.

The sheep/lamb ones did change the sound overall. The different frequencies still had the same balance to each other but something about the overall sound did definitely change. It's like the whole spectrum is in a different tone. Its do-able but not a lot of positives. I've sworn to never use velour so I'm partial to using the sheep leather pads but it feels slightly out of necessity. I assume fenestrated will do better.

The cow leather ones change a lot about the sound. These pads make the headphone a lot darker and shift the timbre to the bass area. I have the 650 which is already quite dark so I don't know how it would sound with the 600. The change might not be as fitting. This option also requires often eq changes depending on what you are listening to. I'm in love with them but this route if definitely not for everyone.

The Yaxi alcantara pads would be the first I would try. They still have fabric but its not comparable to the velour. They are quite open and deep so likely no/little contact with the ear. For the ZMF leather options I would favor the deep oval's over the ori's. The combination of leather and shallower pads are bit too much and sound congested/blurred.