Mono block Preamp

Esoteric makes one-dual power cords need

Seems like I vaguely remember an early Sutherland, 5000 maybe?

Most of the advantage of going monobloc is to reduces cross-talk (channel separation).  Monobloc is of more advantage when there are big voltages running around, like in a power amp.

The volume control requirement in a pre-amp is an inconvenience that will put of many aspirants.

Monobloc phono amps make some sense.

I had a mono Gryphon phono stage back in the 90's.  I think it was simply called The Gryphon.  Four-piece unit  Separate left and right units with a wooden knob on the front of each unit and two separate power supplies  It was a great sounding phono stage. Only one I have ever seen.