From Charles Petzold’s highly recommended article Adventures in Electronic Music. You can read it in its entirety here.

Turning 90° to the left, you can see the windows in my apartment overlooking Broadway, flanked by steel shelving containing my LP collection and a pair of Polk speakers. My bed is to the left. (Yes, this is a studio apartment.) The edge of my piano can be seen at the far left. Little Cat is on the floor.

The synthesizer in its final form was capable of generating 80 simultaneous sine waves, combined in pairs for simple FM synthesis of 40 tones at a sampling rate of 31,250 Hz. For the multiplication of the sine curve values by the amplitude, I used a massive 64-pin TRY MPY16HJ chip, which could perform a 16-bit by 16-bit multiplication in 50 nanoseconds. (How fast can the microprocessor in your desktop computer perform a 16-by-16-bit integer multiplication?) This dedicated multiplier chip cost $241.

Interesting to think about how computer and DSP technology has changed.