I have received my IE80 yesterday. Left it burn in for more than 13 hours throughout the night but it still does not sound good. The bass is less boomy now but still boomy. The treble is less now but still slightly too much. The sound signature sounds like when the EQ is adjusted to V-shape. Slight too much bass and treble. Also, it does not sounds as natural as HD650. I will let it burn it few more days to 2 weeks. Will listen to it again after 100 hours and 200 hours.
I am used to the good quality and sound signature of HD650 using flac -> Bifrost -> Lyr (see my signature). Since IE80 cost about the same price as HD650, my expectation for IE80 is the sound quality is on par or just slightly below HD650. So far I am dissappointed. Currently with 13 hours burn in, the sound quality is no where near HD650. Regarding sound signature, IE80 sounds different from HD650. HD650 sound much better currently. I have tested IE80 and HD650 with my E17. I even tested it them both on my Bifrost -> Lyr. I actually plug in the IE80 to my Lyr using a 6.3mm Male to 3.5mm Female adapter. Both IE80 and HD650 are using stock cable.
IE80 with the 6.3mm Male to 3.5mm Female adapter. IE80 looks awesome (like a bodybuilder on steroid) with the adapter.
IE80 plugged in to Lyr