Wow. So I got to thinking about the sound differences that pad swapping made with YH-1's and YH-100's and decided to try some things with YHD's. I first cut out some foam gaskets to rasie the pads up. The foam was thick so it was almost an entire centimeter difference. In some ways better, but still really "off" sounding. I took the stock pads from the Superlux HD660 (Beyer clone for the RP18 transplant) which were super cheap pleather. Sounded bad, but possibly better than my handstitched pads? Ok, well if those fit, what about the 100mm sheepskin pads I bought off Aliexpress? Yessss, they fit. Whoa, this sounds pretty good. I'm embarrassed to say these sound better now because measurements aren't anything special... Look:
Brown is YH-1 with Suede pads for reference. Purple is old handstitched pads with the belt mod, Blue is Aliexpress pads without any pad sealing tricks, just plopping them on.
Idk why, but the midrange doesn't sound honky anymore, it sounds flat, just a little recessed, but I don't even care, it just makes bass seem more prominent as far as I can tell. Little treble sparkle. Now these finally sound normal, I can actually listen to them. Bass seems different from YH's. I like it, but not quite as much as YH-1 bass. Bass on YH-1 seems bigger and more effortless I feel, but punchiness and quantity maybe goes to YHD. Bass texture coould change with different pads, I feel, so I can't be too judgmental yet. Their image texture is nice, it's very bold like I've said before, but something about the image texture to YH-1's seems more hi-fi and pleasurable to me, there's a softness and refinement to the sound. I might change my mind, haha, Idk, maybe I'm just warming up to YHD's right now... Ok, nope, just verified, the handstitched pads with risers sounds terrible, I wasn't wrong before. Hrm, something about these pads makes YHD's more than listenable.
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Bought Brainwavz Hybrid pads for the CD550, they should fit fine, more measurements comingggg.
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Ok, I can see how you said these YHD-3's compare to cheap Hifiman's. Really, really good.