An Audio Broadcast System Using Delta Modulation
Kenneth James Gundry · SMPTE Journal · 1985
Digital systems are attractive for the delivery of high-quality audio to the home because they can be substantially transparent even under conditions of impaired reception and because they permit scrambling without degradation of quality. Conventional multi-level pulse-code modulation (PCM), with its precise digital/analog converters (at least 13 bit), elaborate output filters, and complex error correction, can perform well, but its cost is much higher than that of consumer audio circuitry. This article describes a digital transmission technique based on delta modulation, whose decoder cost is a small fraction of that of a PCM system.