This is a Casio's CT 6000 flagship model from 1984, and it's a very unusual beast for its time as it had a ton of high level features. For instance, it has MIDI, a velocity AND after touch keyboard, Unison modes, lush choruses, a complex accompaniment section including "Super Accompaniment" that adds fills depending on how the person is playing, a pitch bend wheel with glissando control, and the ability to split and layer the keyboard. These were all rather advanced for a 1984 home keyboard and were not evident in any of Casio's other commercial keyboards up to 1984.
1985 Casio Casiotone CT-6000
Keyboard: 61 keys
Polyphony: 8 notes
ROM: 20 sounds, 20 rhythms
Power Consumption: 49 watts
Dimensions: 980 mm x 340 mm x 122 mm
Weight: 14 kg
This keyboard is MIDI-enabled.
This keyboard has built-in 7-watt stereo speaker(s).