As Craig has plans to re-introduce an updated version of this amp, I am wondering how well the older versions drive the new breed of planar-magnetic headphones and what headphones you have found to be most suited to this amp? I think Craig is also looking to develop a heater supply that is less prone to hum. Do you have any hum issues with your cans?
The pic is of the old S2A3 version.















Plus we're trying to finish off some stuff for the family biz, then there will be holidays and a week of vacation.