Philips Philicorda type 22gm751, Tube Organ, 1966-67, made in Germany

Introduced around 1966 or '67, the GM751 was the successor to the AG-7500. Early versions of the 751 had tube preamps, and later ones were all-transistor. Has a switch underneath that turns the internal speakers of and on.

The Philicorda 751 (22GM751 with various country specific suffixes such as 22GM751/22 for Germany) was launched in 1967, some of them had both valves (preamp stage) and transistors, followed by the 22GM752, which was fully transistorized. A later model, the 22GM753, launched at the end of 1967, was designed for the stage and was fully transistorized.

Although Philicordas, from the AG7400 to the 22GM753, had slight differences in sound, the Philicorda's typical warm tone, produced using cold cathode tube oscillators, was consistent over the years.

Link: combo-organ | wikipedia