hrklg01
Member of the Trade: Mysphere
AKG K1000 developer
I think harmonic distortion measurements – maybe displaying the different orders – would be the best indicator. Better than optical indicators such as oscillograms lacking the necessary resolution .
[ at 90dBSPL in average] amplitude & Distortion THD + K2+K3:
[ at 90dBSPL in average] Distortion THD + K2 up to K6+: