This is a very musical design, tube-like sound class A power amplifier, with reference to Musical Fidelity A-100. The original A-100 was a bigger brother of the most famous ( popular) class A amplifier in the solid state history -- A1. A-100 allowed 50W of power per channel while A-1 gave 20W per channel. In our incarnation, we use the more popular transistors of nowadays to facilitate the diyers. PCB dimension : 135mm x 65mm Board thickness : 1.6mm Copper thickness : 75um( four times normal thickness !) with gold-plated surface finishing. Supply voltage : +/-18V DC to +/-35V DC , 1.5A quiescent current ( to give about 30W of class A operation. Beyond this power the amplifier works in class AB mode) We provide schematic to buyers by EMAIL( to be attached to the shipment notice). We do air shipping worldwide at US$5.00. We welcome combine shipping. Powered by SoldEazy