What is the difference between the old low bias Stax and the newer high bias Stax in sound? I have an old pair of Stax SR-X mark 3's. I am trying to get a feel for how the various Stax models differ.

Newbee question. Can I build a Gilmore Current-domain amp for the low bias Stax SR-X Mark 3? The 250 volt bias is easy. Can I use a +-250 volt power supply to keep within the 500 volt max swing? Would some of the component values need to be changed to accomidate the lower rail voltage? Thanks...