first of all, i'm totally satisfied with my choice!
i thought my er4p kinda had bible-like sound so i decided buy KSC75 for
listening to rock/metal.
unfortunately KSC75 were temporally out of stock
so with a couple of recommendations from my japanese friends,
i purchased E931 as an alternative to them
In fact, Sony's been making these for more than 10 years.
i was actually afraid of buying one more cheap sony earphones after EX31
(they were also pink! i initially ordered swanky blue)
when i first connected right-out-of-the-box E931 to my ipod mini with
rockbox, i was surprised that they don't sound like any of those
cheap "Sony" earphones: boomy, murky, muddy, possibly disgusting...
you know lol
before the mod, E931 sounded somehow boomy like grados, not my type, but
after an easy mod, removing a layer of filter inside,
their sound became sharpened and much more detailed overall.
IMO modded E931 actually sound more favorable than other earphones i've got,
AKG K14P/ETY ER4P (too clinical), SENNHEISER MX400 (murky),
also including PX100 (boomy, cloudy, hidden treble, ew)
the bass is sufficiently heavy but short at the same time
& the treble is, well, like a wild horse but no unpleasant resonance or harshness
most significantly, the mid-range approached much closer to the ears,
the word i'd describe E931 is "direct." i can actually feel vibration from
these tiny earphones despite a small volume
for those who are seeking for inexpansive, worthwhile headphones,
but wantting to discover something different from others
E931 are definitely a considerable choice!
P.S. the wires made out of cloth

, not rubber.