Veteran phono-preamplifier designer Ron Sutherland has been partial, of late, to battery power. Getting off the grid can produce superb results, as demonstrated by his Hubble phono preamp ($3800), powered by 16 alkaline batteries.
I favorably reviewed the Hubble in the February 2010 issue, and remember loving most everything about itparticularly its drop-dead-quiet backdrops, its solid, weighty bottom end, and its fully fleshed-out instrumental textures. I was less enthused by its somewhat soft, muted high-frequency transients, though of course tastes and associated gear will differ. I need more grit, particularly for rock; you may not.