For measurements, I am using the same in-ear coupler as my friend on, the IEC 60318-4. I am posting raw measurements, which means I have not compensated them to any target. The curves are smoothed according to psychoacoustics in REW.

Visit Headflux for more measurements and first-class reviews in German.

While the in-ear coupler is good and fairly accurate, it cannot replace or fully represent actual hearing impressions. There are several sonic factors that the frequency response does not show but that do translate to the quality of an IEM. Please be careful when trying to judge the quality of an in-ear system by the measurements alone. I will link to personal impressions if I have featured the IEM in an article.