Some of the new pads I ordered have arrived, and with some brief testing on my german ref II's, here are some of my subjective impressions.
For context I have been using very flat ref II velour pads, with what could either be original (though I doubt it) if not HD430 inner/filter foam, and I have kept to this foam disc throughout the tests to eliminate that as a variable. Due to the flatness of the ref II pads, the tops of my ears rest slightly on the inner filter foam disc, not enough to hurt, but seems worth mentioning.
First pads up are wang yifei 'velour'. I put velour in quote marks, because the material is quite different to that of the ref II pads, with very long fibers, they're fluffy like a cushion cover, and this material looks nothing like the picture on the ebay ad. Before testing I carefully cut out the thin material dust cover thing on the back, as I didn't want that to interfere with anything. As I dont have a spare mounting/retention clip ring, these are just pushed into the cups and holding themselves in with friction, and I cant tell you at this stage whether or not the lack of a ring would make an impact on the sound. I note by looking at them that the hole in the middle of the pad is quite a lot narrower than my ref II pads. Pad height (or depth) is exactly twice that of the ref II pads.
The first thing I notice with these is that the volume seems lower, which is interesting, because I also have an uncomfortable pressure in my ears like I have the volume turned up way too high. These sound much less open, with a reduced soundstage. Immediately noticeable is the lack of clarity, like there is a thick veil softening and masking details in general. I had expected there would be more bass due to the significantly higher amount of foam in these, but in fact, there is less. Switching back to the ref II pads feels like a relief.
Second pads are HD430. Confirmed the plastic mounting ring is a perfect fit, so worst case scenario I can harvest these rings for use on other pads. Pad height is equal with ref II's.
The hole in the centre is wider than the wang velours, though still a bit narrower than the ref II pads. These are a bit uncomfortable, as the tops of my ears and earlobes now rest against the inside edge of the pads. As someone with medium sized ears which do not protrude overmuch, and it takes some fiddling to get them comfortable enough not to annoy me. I think this will be a big issue for someone with larger ears, unfortunately.
Unlike with the wang pads, the clarity doesn't take quite as big a nosedive at least for intruments, but it is still reduced, and vocals dont sound good anymore. Once again this feels less open, and soundstage is narrower again. Being a more sealed fit is an oddly noticeable sensation. The bass has increased quite a lot, and now sounds like its too much, which changes the overall signature to being muddy and covering details. Treble is a bit bright/hot, with some sibilance. Switching back to the ref II pads is a relief once more, everything becoming clear and wide and open. There is a lot less punch, but the bass is a lot cleaner and doesn't intrude on the mids anymore, and it also shows vocals to be far superior in clarity.
Overall neither pad really impresses me, and in both cases, switching back to the flat ref II velour pads instantly sounds like an upgrade. I dont want to give up that clarity, or the wide soundstage, and wont compromise on those areas for anything; I want to make those elements better! So, where to next?
I have some pu leather earpads on their way from china, the ones recommend by 2leftears. I also have a sheet of 1" thick high density polyurethane upholstery foam coming, and will be using cookie cutters as recommended by o0CosmoMemory0o.
My intention is to try replacing the foam in all four sets of earpads, and see whether I end up with a winner along the way, and I'll come back with an update later