Has anyone here heard significant improvements by throwing more expensive/powerful solid-state amplifiers at the HD650? I used it with a Fiio E10K (High Gain), O2, Schiit Magni 2, Violectric HPA V90 and JDS Labs The Element. Changes were extremely subtle, almost non-existant.
Tried the HD-650 with a Liquid Gold and McIntosh MHA-100, there was a subtle but noticeable difference to me in these two amps vs a Asgard2 or G-109, and it also sounded difference from a Liquid Glass and EC Balancing Act, better? maybe, but its still an individual preference.
There is also a subtle difference between my BH Crack, Ember and Lyr2, I like the presentation from the BH Crack best but I wouldn't call it better than the Ember, just more my taste.