A developer describes the CZP-1, a web-based Casio CZ-101 synthesizer emulator that loads patch data, stores banks in browser storage, and enables sound sharing via encoded URLs without server-side storage. The project incorporated patch data from a YouTube creator using AI assistance to convert MIDI system exclusive files.
The CZP-1 is a web-based software synthesizer implementing Casio's phase distortion synthesis technology from the 1980s. Built using collaborative AI agents (Claude, DeepSeek, Codex), it features a complete instrument interface with sound banks, MIDI support, and shareable preset links. The development process involved iterative refinement across multiple AI systems to achieve accurate audio synthesis and functional UI.
The author modified a vintage Casio PT-10 toy keyboard to add programmable synthesizer capabilities by enabling the ADSR voice feature that was present in the related Casio VL-1 but omitted from the PT-10. Using the PT-10 service manual and VL-1 documentation, they made surgical modifications to the PCB by cutting traces and adding jumper headers to access calculator mode for programming custom voices with eight-digit codes that control envelope, vibrato, and tremolo.