Grover Neville, Upscale's personal audio guru, dives fearlessly into the Abyss, bringing back boatloads of information on the Diana TC, advertised as the world's thinnest boutique planar headphones. He contrasts it with other Abyss models and helps you choose the right headphone amp. Abyss Diana TC Headphones: https://upscaleaudio.com/products/abyss-diana-tc-headphones Abyss AB 1266 Phi TC Video: https://www.youtube.com/watch?v=rRfApjEW7eE Feliks Audio Envy Headphone Amplifier: https://upscaleaudio.com/products/feliks-audio-envy-headphone-amplifier Pathos Aurium Headphone Amplifier: https://upscaleaudio.com/products/pathos-aurium-headphone-amplifier Pathos InPol Ear Reference Headphone Amplifier: https://upscaleaudio.com/products/pathos-inpol-ear-reference-headphone-amplifier