Just to add to my last post...
I'm listening to my h3 through my f806 - e12 as a source. No bass boost, no high gain. I'm currently bouncing back and forth between the mh1 stock tips and the heir tips found on lunashops. I've been listening to them exclusively at home, and have been comparing them to my other favorite iems (check my inventory if you're wondering what that is)
The sound of my h3 is much different from the iem I heard the first 100 hours. Burn in is real! At least on some iems!
What I hear now out of them is a very balanced and controlled bass response that extends as far as I can hear. It is prominent from the sub layer all the way up and through the mid-bass and into the midrange. I hear no bleed whatsoever. I think some might perceive a bloat or a bleed, but with higher quality tracks and sources it's actually very well presented in separation and texture.
Midrange is spot on. Separation and imaging is seldom rivaled by any iem I've heard. It gives an out of the head feeling. It really shines when multiple vocals and instruments are playing at the same time. Separation is consistent and doesn't ever seem to ever get overwhelmed. I can pick out any particular sound on a complex track and focus in on it, and it's sound never will get distorted or smeared.
Treble is very present and with better than average detail. It gets as bright as it can get without becoming sibilant. There are parts of songs where with some iems I will almost have to brace myself for the impact that the sibilance will have with my ears. I NEVER have to worry about that with the h3. The ex1000, altone200, and even sometimes with the GR07BE, the sibilance has a fatiguing effect on my listening experience. Some will knock it, saying it's "unnatural" or "not as extended as...", but I think the h3 is superior in the sense that it is what I consider fatigue free treble. It is still very present, relatively well extended and not lacking or rolled off whatsoever IMHO.
Soundstage width and separation is world class. Soundstage depth is about as good as it gets, and height is very good. Separation is phenomenal.
I own sets of iems that do surpass it in terms of detail (altone200, KC06, havi b3 pro1 just to name a few) but all things considered, the h3 is the total package. It takes bass lovers and audiophiles and strikes a balanced product in the h3.
Reviews can sometimes be discouraging on these. It's unfortunate if it caused some to be reluctant and not purchase them. They can currently be had for around $250 usd. That is a great price on a great iem. I hope more people bite on them, spend some time tip rolling, and give them 100 hours of play time/burn in. I'm sure many will be pleased with what they experience.