Sonab C-500 cassette deck (1974-1975).
The C-500 was made by Nakamichi and was, in fact, a repackaged Nakamichi 500 Dual Tracer in a piano-black "designer" shell (Dieter Rams, perhaps?). It has user-accessible recording calibration trimmers on the back, like a real Nak but missed the patented limiter switch of the original model 500. According to naks.com, the 500 was also sold as Advent 200, Concord MK-IX, Wharfedale DC9, Sansui SC-700, Fisher RC-150, Goodmans SCD100 and probably others. 

While the original Nak 500 sold at least into 1978, the Sonab didn't do well. The company - already taken over by the Swedish government to save it from bankruptcy - was on its last legs. They tried to get a slice of premium "designer hi-fi" segment (occupied by B&amp;O and company) and it did not work out. The C-500 and its siblings disappeared from Sonab's catalogue after 1975; by 1978 the company was officially dead.
Own work
Retired electrician