I have 2 x ADI-2’s
But in the 20-100kHz region, my SMSL D-6 outmeasures my ADI-2 in most measurements when fed DSD512 (running in DSD Direct mode). ADI-2 is has a bit better filtering of ultrasonic noise.
D-6 has dual AK4493S chips - so cheap! With balanced outputs. Need to make sure you load the latest firmware though for best performance.
They all sound identical to me though - it’s just more pleasing to get to DSD512 in DSD Direct and without tradeoff in performance…
Having said that, my ADI-2’s will be with me forever ! It’s a classic.