# Sonata: making chess audible

Technical overview · September 15, 2026 · TriunaLabs

Sonata powers ChessJammer's Classical recorded-game soundtrack. The arrangement combines sampled grand piano, two-handed writing, inner voices and orchestral responses. Recurring musical identities belong to individual chess pieces.

## Current public demo

The public demo starts from ChessJammer build 454, preserved independently of the IGF jury deployment. Captures, threats and sustained king danger shape the arrangement. The scene director selects and spaces existing orchestral material. Recorded clock data is used where available; untimed games use simulated pacing rather than claims of historical thinking times.

## Sound and samples

The piano uses an adapted Salamander Grand Piano v3 sample set. Asset credits and license information accompany the game. Sample quality, musical writing and instrument balance are distinct parts of development.

## Research, not a feature claim

Current experiments investigate directional initiative, persistent defensive obligations, and changes in geometric attack/protection relationships. Legal captures, engine continuations and alternative defences are reviewed separately. A geometric attack is not proof of a forced threat; an engine principal variation is not proof that every reply fails. These experiments are not yet public-demo musical controls.

## Design boundary

The board supplies the changing situation, piece identities supply recurring material, and the arrangement governs performance. Research aims to make those relationships more audible while preserving continuity and musical space.

This is a public technical overview, not a peer-reviewed paper or the internal implementation specification.