Direct Heating with the Sakuma System

by Susumu Sakuma

from Issue 13 - Sound Practices

My old friends, VT25/801A push-pull pre-amplifier and PX4/PX4 SE power amplifier began singing "Manha de Carnaval" from Black Orpheus with a Lowther PM6 unit.

Under the misty spring sky, in my dimlylit restaurant Concorde, I Iean against the brick wall. A cooling breeze through the window brushes my eyes.

I see a scene over the breeze-- that summer day when I made the amplifier, the 845/845 push-pull monaural power amplifier...

My two friends work in the lane outside the Concorde's entrance punching holes in an aluminum chassis. They have to finish the work before the noon hour, because it is very warm in the summer afternoon and the entrance must be clear for guests to have lunch.

A wood plank on two beer crates is my workbench for chassis construction. One guy drilled and another filed the holes smooth, wet with sweat. I bring cold Japanese tea to them.

A few humble tools and the workshop under the blue sky. Simple circuit design and old style devices, transformers and triodes. I have made my many amplifiers with these elements.

Can the engineers in the clean room with air conditioner and computers make amplifiers which can tell us the passion of the players and convey the strenuous efforts of the composers?