Did some work on a alpha 8 cd player. Couple of warning words , the ribbons that attach the dac modual to the main board are are a pita to reattach and like to peel contacts. Also the traces on the pcb are very prone to lifting so keep dwell times down to the minimum.
Maybe Arcam improved...
Took a look at the measurments for that headphone. Seems to have a bit of wide peak centered around 15khz. That could be fatiguing over time aka increasing brightness. If you can , chuck a PEQ peak filter in there at 15khz -2.5db Q1.5 (guesstimate). See if that helps.
Been playing with it the last couple of days using LG V30+ as mic. It kinda works. Below about 400hz it seems to produce reasonable results. Results are very volume dependent though with swings of 10db dependent on test volume mostly below 50hz.
Going into the midrange and treble gives really...