MusicaAcoustics

Woo Audio is very good, but you don't need such large amp for Woo Audio. Recently I try the GoDap Unit 4 with Q701 which was perfect no matter it so small. And it sound great with Benchmark HDR 1 or USB 1. There so many good sounding devices for the Q/K701 headphones.

There are so many option in balanced headphone amplifiers portable and home. Mentioned here was the headroom one. It is very good but very big. You can get true balanced headphone amp from iBasso, Ray Samual, MST, even GoVibe is making one. Price is concern as all are very expensive. Good luck!

Recently I tried the Vorzüge portable headphone amplifier with bass and treble buttons. They add so much bass and treble to help headphones bring maybe something they lack in first place. Grado are very cool for attack and recovery but not always nicest bass. VorzAMPduo made them great. Good luck with your search!