Nice comparison and nicely done. Very helpful and useful info. What other equipment are you using in terms of amp, DAC, etc.? I started with the HE400S, which is really quite good for the $, and then moved up to the Arya Stealth that offers more of everything, as it damn well should for the much higher price.
I’m running mine with a Singxer SA1 Class-A amp fed by a Denafrips Iris DDC that feeds i2S via HDMI to a Musician Pegasus R2R DAC and sounds great with either headphone. All connections are made via LavriCable silver balanced interconnects and headphone cable. I’ve got a Linear Tube Audio MZ2 tubed preamp/headphone amp (with upgraded linear power supply) in a box waiting for me to listen to that should be a nice upgrade — I hope. Anyway, look forward to hear what other equipment you were using to make your comparisons as that’s always helpful info for perspective. Anyway, thanks for the nice comparison!