Detail: 
• This amplifier circuit contains only main amplifier. 
• There is no tone and control. 
• The circuit is OTL so no problem regarding burning speaker concern when output of transistor is shorted. 
• This circuit needs 40 – 50V. 
• Power supply : 31-0-31 or 33-0-33V.
• 1.5A. transformer
• PCB dimensions : 4.7” X 1.8”