I have a fair bit of experience using more analytical IEMs, Phonak PFE112, hifiman RE400, RE00, and even the UERM. They were all really satisfying, and my obsession finally led me to the very definition of analytical IEMs, the ER4 series. I wanted something different this time and went for the ER4XR for that extra bit of low end, seeing how most reviews mention that the differences between ER4XR and ER4SR are very slight. And the ER4XR was a surprise to be sure, but truly a welcome one. In my experience, a balanced IEM at the right volume sounds complete and just... right, and this matches that experience well. But man do the voices sound so satisfying and clear. But I'm not sure if its because of my prior experience, since I have been using the RE00 very often nowadays, but the bass on these are fantastic and do make their presence known, and yet still allows for the satisfying balanced sound that I so love. I always had the fear that the king of accurate BAs would sound tinny, but I am glad I finally found these, because I am in love.