A few recommendation of recordings for evaluating Clarity Headphone Amplifier

Ririko's Violin Piece Collections are all stereo recorded very well. You hear the violin moving around while she was playing. The instrument used is also a Stradivarius "Lord Borwick" (1702).
Note that the first video is a playlist including 160 pieces. 

This recording of Vivaldi Winter is probably the best on the internet in terms of audio technical perspective. 

Saturday Night Live in recent years all have very good stereo recording. Turn the CLEAR SOUND switch ON on Clarity Headphone Amplifier, and enjoy the surround sound. Hear the drastic differences in sound stage of the audiences' laughs. 

Well recorded violin piece for millennials audience. 

A digital remastered vinyl record.