I has taken R-07 from a friend for some days.
I didn't understand them for the first couple of minutes, but later i became shocked.
They were great on his Tascam portable recorder, but not on my iPod Touch.
So i was trying to understand them and i did it
Soundstage is really big deep and wide very beautiful. Sound is little thin but very good. They are very natural and neutral.
Bass quality is very good but not too punchy for electronic music and hip-hop. Mids are great and detailed. Treble is not very good. Great vocals.
If you rise up your volume level you will have better bass response it is good for electronic music and all sound will come more forward.
They are really great for hard rock, hard core and metal music.
I don't know a lot of earphones which can make such things (Shure 535, Triple Fi, Monsters, Pro Monsters).
They are fantastic even without amp.
I like this sound.