- Feb 3, 2020
- South East Asia (not China or SAR's)
The 990 can do 200+ mA into 75 ohm.
Yup, that is what I mean with sufficient drive current.
I usually aim for 0.7A peak repetitive and sustained and expect more than that as single pulses...
Why? Planar headphones from 13 to 50 Ohm with SPL between 86dB to 100dB/V.
These headphones can hit -80dB THD acoustically, so amplifier distortion should be -90...-100dB "simple" THD at several volt into low impedance.
If you ask me, with these planar headphones available all common dynamic types are declasse, incompetetive and only use for non quality critical tasks (eg. not suitable for tracking, mixing or mastering).