ZX Spectrum System Tour: Sound

The ZX Spectrum had two sound options: a 1-bit beeper present on all models and an AY-3-8910 synthesizer chip available from the 128K models onward. The beeper operates similarly to the Apple II speaker, with specific tones produced by timing intervals between bit toggles, and the system includes a BEEPER routine at memory location $03B5 that can be called directly. The article demonstrates how to generate tones by providing formulas to calculate the frequency and duration codes needed to play a C-major scale on the Spectrum.