It was in the years 1973 to the top of the receiver and the output power as well as the interior. 2x 50 watt continuous sound power was anything but ordinary at that time. Nor did 2 Aux and 2 tape connections or high- and low-frequency filters belong to the "standard equipment". This was also noticeable in the price, because the average income at that time was about DM 1500.-!
Device presentation of Armin777 aka Good Old Hifi in the Old Fidelity Forum