Smaller sibling to the KA-1000 - single transformer, integrated power supply and a smaller Heat-Pipe. The rest is nearly identical.
With High-fT transistors, a DC...400Khz bandwidth, 2x 80W (20Hz...20Khz), a slew rate of ±120V, a 0,9µs rise-time and a 500 damping factor at 100Hz, the KA-900 was a tight and futuristic way to start the 1980s... even if made of plastic.
The non-magnetic chassis always is a suprise to discover "in the flesh"... it is made of plastic !
This explains the somewhat sloping parts and top covers one can see in the catalogs : plastic doesn't like heat nor does it age well.
The front window of the KA-900 is however made of real glass, not easy-to-scratch acryl or perspex.
The KA-900 was a fine example of high-end Hi-Fi navigating between the 1970s robustness and 1980s trendy trends in technology as well as design.