These HEM8's are my new favorite IEMs. I've been hunting for ideal in-ears for some time. Prior to these, I would toggle between the UE 900's, Shure 535s, and the Massdrop Plus Universal's. I find the HEM8's to be very efficient and are easily powered by my Pixel 2XL with usb dongle, but get even better when I pair them up with an amp. I have aTopping DAC & Amp at my desktop, and then and Earstudio ES100 bluetooth DAC/AMP for mobile (which I also highly, highly recommend) that really make the HEM8's shine. Soundstage is broad, detail is great, and I'm not fatigued when listening to them. I listen to lots of lossless recordings of concerts, and these give me a strong feeling of "I was there" that is very difficult to reproduce in headphones... I'll buy them as gifts for my friends.