i have the e5s and just got the 6is. i have to think from all the descriptions i've heard that the e5s will not give you the highs you're looking for. i guess i should lay down some caveats first. i'm no audiophile. i haven't owned/listened to a whole line of 'phones. i think i'm subject to some kind of hearing peculiarity that caused the xin super dual to give me a headache. perhaps even worse, i got the 6is not out of intellectual curiosity or a desire to hear something better, but because i have small ears, small ear canals, can only wear the e5s so long before my ears hurt and needed something to wear while running the weed whacker!
that said, with a 3g ipod, there's no comparison between the e5s and the 6is if you want bass (i'm no basshead, though). using "kind of blue" as a comparison point, with the 5s there is a deep, reverberating bass line that i hear. with the 6is, i can hear the bass, but it's more in the background. on the other hand, on the 6is, i can hear the drummer's brushwork better, though it can sound muddy at times on both the e5s and 6is (could just be i need to encode differently, though). both sets of phones handle montserrat caballe hitting that high note in "casta diva" without that crackling sound i get with the apple ear buds and other cheapies i use while running errands. so far i find the overall sound of the 6is brassier (yup, that's brassier, not bassier), but not so metallic i want to clench my teeth. i think i would probably suffer from fatigue if i wore them too long. but will i keep them? yes. they will work for what i purchased them for.
i have a feeling for that perfect balance in an earphone some want, people may have to go for those iems being discussed at head-fi. on the other hand, isn't that why the head-fi password is "sorry about your wallet"?
