I bought a pair of these a few years ago but only recently opened them up to use. I used the MDR-e10 version which I think (1) fits better (headphones are slightly smaller) and (2) sounds much better. In the A/B comparison, the 9s sound very tinny with a small base, while the 10s have a much fuller sound and reasonable bass presence. Unfortunately the 10's have been discontinued but are still available.
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