After reading and researching in this great forum on what IEMs to bless my ears with i decided that the GR07 would be the ones with my particular music taste in mind, being that i listen to mostly Metal. I would like to share my experience with the VSonic GR07 and how i tamed the sibilance.
Upon receiving my package from Amazon from a seller i dont rightfully remember (it wasn't lendmeurears) i was almost positive i received fakes, as the sibilance was untamed and very unnerving to my ears. i tried my best to push through it and see if it went away after a while but i had little luck in getting it to be less intense, i could hardly listen to anything without turning the treble to the minimum causing my music to sound very unnatural and undesirable. i was at ends with my purchase and very unsatisfied but my persistance in fixing the problem caused me to go over the return period. I would not give up though, these had to be real and i would force them into submission.
I began by plugging them into my Little Dot MKIII amp at full and having my Cowon J3 at full and playing random music through them for hours on end, honestly i can't recall exactly but i would assume they had 100 hours at that point, that managed to do very little and so i thought maybe it was the frequencies that had to be played through them, i then turned my J3 to the radio app and found a non used frequency and threw full volume static through them for another 20-30 hours. I can attest that these little guys can take a punishment like none other! However that too failed to resolve very much, though i was noticing a cumulative affect on the 07's as in each time i listened i did not hear very much difference but looking back at what they first sounded like i can assume that they have changed slightly but not enough to be satisfied.
As i kept searching i came across threads suggesting the right tips and foam inserts etc etc but i already had a good seal as my ears are large and i had the largest tips on them and had yet to get leakage so i knew it was not my accessories causing issues. I decided i would see just how much abuse these would take so i set the EQ on the J3 to the "rock" setting which had the worse sibilance on every track and slightly raised bass tones, not enough to make it absurd but it was slight enough that it didnt seem unnatural, just loud. i set the volume at max again and decided to play "Borgore" through them for another 24 hours. I thought that maybe the movement of the bass with dubstep might cause the IEMs to either blow or get them burned in properly.
It worked, now the sibilance is still there and noticeable but i can turn the treble up finally to above flat level and i can hear the music as it was intended. i know as time goes on that the sibilance might go away even more but at this time they are very good sounding and i dont feel the need to subject them to more abuse. The bass is rock solid and not bloated but clean and it goes deep. the treble goes high but ends at the sibilance.
Total time until satisfaction ~250 hours
I can't contribute much to this forum as there are many more experienced than I but i wanted to give back something, hopefully this information helps somebody
TL:DR Give them abusive bass to tame the sibilance
