ToneLeak

Ongoing independent research auditing whether guitar-tone models change only the requested production tone, or also change performance attributes that should stay attributable to the source player: bends, vibrato, articulation, attack and dynamics. It does not assume tone and touch are separable — a deterministic effect applied to the exact same DI performance supplies counterfactual ground truth. A pilot audit of 2,040 published Fx embeddings found intended tone decodes at 99.3% balanced accuracy while source combination stays at 87.3%, so the public representation is tone-informative but not source-invariant. A held-out causal reference swap then confirmed the output shifts under an identical query and tone target. Projecting out the source-predictive subspace reduced leakage but raised target error — reported as a negative result rather than a fix.