Bona F Pardede
Head-Fier
Just tested U12 w/Ref8 (2.5mm terminated) and M15 module directly with R6. Comparing it to Plenue 2, my current neutral reference source, R6/U12/M15/Ref8 pair up scales up in clarity and resolution, and I mean significantly. I have it connected directly, and this is a perfect example confirming what 64 Audio said about U12 being originally tuned for higher impedance sources (performing stage musicians with wireless packs). To improve the clarify with my other sources, mostly upper mids/lower treble, I had to use impedance adapter with U12, and I still wasn't able to get to the same level of clarity as I have here directly from R6. Again, take it on case-by-case basis, this is not a general assumption about every IEM pair up with R6, but a specific example of U12 w/R6.
So, the clarity went up, but bass slam is a bit lower in quantity. I was always using U12 with M15 module, just for the purpose of lowering the bass impact in my original setup (M15 has less isolation, and less bass). Now, I just switched to M20 module, and the bass slam is back in your face, with the same clarity and resolution, just a little less airiness.
Yayyy, I guest that I made the right choice after all. Thanks @twister6 for your review.
Update backers on the Indiegogo already reach 150k.. so tempered glass and free case unlock guysss... yipieeee