The Space Heater is a simple 12AX7 preamp designed to give some yummy tube warmth with a little bit of breakup in a compact package. The gainstages are set up similarly to Particle Accelerator so there is some shared DNA with the Alembic F-2B.
With the gain low you can crank the volume without it breaking up, though obviously is will push your amp HARD as it is a high output circuit. Add some gain and you can get varying levels of breakup, with a nice hairy drive when the gain is cranked.
It can take a 9V or 12V input, and can accept center negative or center positive inputs. It uses internal regulators 200V to the tube plates, giving it the richness you expect from a full high-voltage preamp.
CURRENT DRAW NOTE: Like many Sushi Box pedals, this one uses a tube, which means current draw is a bit higher than a standard pedal. Warm up numbers have not been recorded, but after warm-up the preamp pulls 240mA from a 12V supply or 210mA from a 9V supply.