This amplifier was built based on Sakuma schematic which was introduced in MJ magazine. Inside the amp used all TAMURA transformers, same as Master Sakuma used in his product.

Sakuma amplifiers dont have much of power, it bring much of energy as his aim. He used many transformers on his amplifier to get the much of enegry and fame of tone.

Sakuma never made amp for sale, he made amp for his system, which use Lowther and Altec speaker

Original schematic of the amp here > https://www10.big.or.jp/~dh/work/0902.html

Here is what people said about Sakuma amplifier.
Some say "The Sakuma amplifier is the finest for music listening "; while others say "Judging by his circuit design, Sakuma must not understand audio electronics. His amplifier may destroy speakers".