Rob, Hyak was the company that made it. They lasted about a year in Belleview, Washington, and produced about 100 basses and guitars in the late '70s. I believe one of the founders was a former Alembic employee. They could be run mono or stereo, and came with a power supply and 5-pin cable, similar to Alembic. And thanks for the compliment. Henry's old Series II sure is sweet!
Bill, tgo