Written by Ian Schmidt (Last updated: 3 November 1997).
The 5503 Ensoniq Digital Oscillator Chip (DOC) contains 32 fundamental sound-generator units, known as "oscillators". Each oscillator is capable of either making an independent tone by itself, or of being paired up cooperatively with its
neighbour in a pairing known as a "generator". The generator arrangement is used by most programs, for it allows more flexibility and a thicker, lusher sound.
The DOC plays 8-bit waveforms, with the centerline at 0x80 (128 decimal). This format is known as "8-bit unsigned". 0x00 (0 decimal too) is reserved for 'stop'. If a sample value of 0 is encountered by a DOC oscillator, the oscillator will immediately halt and not produce any more sound. The DOC additionally has an 8-bit volume register for each oscillator, with a linear slope. The dynamic range of the DOC (the 'space' between the softest and loudest sounds it can produce) is approximately 42 dB, or about on par with an average cassette tape.