Hello,
There are few options available here... The HeadRoom Desktop Amp in conjunction with the Astrodyne Power Supply will work quite nicely for all configurations except the Max DAC option, which remains a very 'power-hungry' D-A stage and needs the upscale Desktop Power Supply (DPS) to show the listener its full sonic potential -- In fact, the Max DAC sounds slightly 'off' to me in the Desktop Amp w/o the DPS
The linear-regulated AC power supply (wall wart) we provide with the Desktop Amp will be just dandy for properly powering all the electronics modules, including the Max module... Keep in mind it is the DAC that demands the serious juice, so a Desktop Amp without a DAC can effectively use the provided wall-wart with absolutely no worries!
Hope this helps a bit!
Cheers,
Jorge
HR Sales & Product Manager