Equipment

Roland D50

Cale used this instrument on Songs For Drella. From Wikipedia:

The D-50 was the first affordable synthesizer to combine sample playback with subtractive synthesis. The engineers at Roland determined that the most difficult component of an instrument's sound to simulate realistically is the attack. To better emulate realistic sounds, the D-50 included almost 100 attack samples in ROM. The synthesizer played back an attack sample which was dove-tailed with more conventional subtractive synthesis to create the sustain of the sound. This dual-use method was required in 1987 since RAM was so expensive. Roland did, however, incorporate a number of "texture" samples that could be mixed into the synthesized sustain-part of a patch. These sustain samples gave many D-50 patches a lush and airy quality.