My pair of DT 770 Ms sound awful with the lightning to USB adapter, even though they're only 80 ohms. But I guess if you're using high impedance headphones it c

My pair of DT 770 Ms sound awful with the lightning to USB adapter, even though they're only 80 ohms. But I guess if you're using high impedance headphones it comes with the territory that you may need an amp. For me, they sound good driven from my iPad pro and a USB C charging/headphone adapter so I listen from that at my desk.