Killer Synth Emulation and the Preset-to-Prompt Pipeline

A technical paper on a software emulation of a patchable vintage synthesizer and the pipeline that turns its presets into prompts for AI music generators Summary for Zenodo This paper documents a two-branch software system built around a software emulation of a vintage patchable analog synthesizer called “Killer,” based on the Ionic Performer and designed in the style of EMS Synthi-type instruments. A single preset file serves as a shared data contract. The audio branch renders the preset to stereo PCM using a sample-by-sample DSP engine that includes oscillator drift, keyboard tracking error, switch-matrix routing, a state-variable filter, a Schroeder reverb, and a signature “Killer Mode” imperfection stage. The semantic branch classifies the same preset into a sonic profile (character, envelope, wave, era) using a deterministic priority-chain classifier and converts that profile into Suno-style text prompts with genre, mood, texture, tempo, production tags, a title, a description, and optional lyric seeds. The paper describes the system architecture, signal flow, routing math, classifier rules, vocabulary banks, and JSON/TXT/CSV export formats. It also reports several defects found by tracing the published rules by hand, including unreachable classes, shadowed rules, boundary brittleness, dominant-wave collisions, and matrix blindness. The source code was written but not executed, and no AI audio is produced by the codebase; the prompt branch steers external services such as Suno or Udio. The work is offered as a transparent, explainable baseline for preset-to-prompt translation and includes recommended next steps for empirical validation, rule repair, matrix-aware features, coherence constraints, and closed-loop evaluation against generated audio. Chris Johnson is a mastering engineer and the founder of Airwindows, a one-person audio DSP project that has released free, open-source plugins since 2007. Based in Vermont, Johnson spent the first decade of Airwindows selling plugins commercially before shifting the entire catalog to a donation-supported model in August 2016, citing a desire to put professional tools in the hands of musicians who could not otherwise afford them. The Airwindows catalog now spans hundreds of tools—from console emulations and tape saturation to ladder filters, clippers, and cross-feed algorithms—released under the MIT license with no DRM and deliberately stripped of graphical interfaces so that users judge sound rather than visuals. Johnson is known for unconventional DSP ideas, including the Console system's "negative distortion" approach to stereo depth, and for releasing new plugins at a rate of roughly one per week alongside explanatory YouTube demonstrations. Beyond software, he has designed hardware guitar DI boxes and published work on hand-antialiased fonts. His work has built a cult following in home-recording and pro-audio communities for combining serious signal-processing research with an explicitly anti-commercial distribution philosophy.