If you want comfort then look no further, they feel MUCH better than the stock ATH pads. The price is great as well when compared to high end pads (Dekoni, Brainwaves, etc.). They do alter the sound compared to the stock pads, not sure if I would say they make my ATH-M40x sound "worse". I'm not sure how to articulate how they changed, but it is subtle and they sure don't sound bad afterwards, just different (possibly a little more airy?). If your stock pads are crumbling like mine were, and you'd like to gain some extra comfort, then these are solid.
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