This is four pieces of bare PCB of a mosfet output power amplifier plus 2SB716/2SD756 per each channel.

Background :  Aside from audio guru Yasui Akira,  Kizuka Shigeru was another prolific contributor to Japan audio magazines. He published his designs in Radio Technology Japan Magazine ( sometimes called Craft Audio). He also wrote books for audio amateurs back in 1970's. His focus was on power amplifiers, in particular complementary symmetric structure and multiple power amplfiers for electronic crossover systems. 

This design has a lineage of Yasui Akira and Hiraga power amplifier architecture. This power amp is unique in the sense that the output devices are lateral mosfets( originally 2SK134/J49 and now we replaced with 2Sk1058/J162). This simplifies the biasing scheme and without worry for thermal runaway even operating at a moderate power ( 45Wrms at +/-38Vdc) at high biasing( quiescent current 250mA ).

Sound performance : the amplifier gives a wide-open and relax sound similar to Hiraga with the added bass authenticity from lateral mosfet. 

If you are looking for a medium power amplifier with simple circuitry , very good sound and tired of hugh heatsink as in Pass amps, then this can be your next project.

This listing is just for the two bare boards. The assembled board is for reference only.

Supply voltage : 32Vx2 DC ( when driving stage and o/p stage Vcc tied together) , or 32Vx2 DC and 38Vx2 DC ( when driving stage and o/p stage Vcc separately supplied)

PCB dimension : 75mm x 90mm.

Frequency response : 10Hz - 160KHZ +/-0.5dB