Evolving prompt+sampling to push VoiceNet dimension VALN in the high direction with the vn_VALN__high LoRA. Steering phrase: bright, positive, cheerful affect.
Best in-direction score 0.676 at 100% vs neutral 0.256 (shift +0.420).
Method & reproducibility — how the evolution ran
Base model:laion/moss-tts-local-transformer-4.55b-voice-acting-v2 · LoRA: the new VoiceNet-dimension LoRAvn_<CODE>__<high|low> (retrained with ≤25% game-character data, rank 32), applied via PEFT adapter scaling at strength λ. Algorithm: genetic search — population 12, 10 generations, elitism (top 5). During evolution every genome is generated best-of-6with the LoRA at λ=100%; its fitness = the mean over those 6 candidates of the target VoiceNet dimension score in the intended direction (for a __high LoRA the raw score; for __low, 1−score), minus 0.2·max(0, WER−0.6). Genome (what evolves): the GENERAL voice description, the SCRIPT cue, the carrier sentence, and the sampling params (temperature, top_p, top_k). λ is fixed at 100% during the search. Mutation operators: 40% regenerate description, 25% swap carrier, 17% jitter temperature ±0.1, 18% change top_k. Offspring = 60% crossover + mutation, 40% mutation. Dose measurement (below): the winning recipe is then re-generated at λ=0 (LoRA OFF), λ=50% and λ=100% (each best-of-6) to show exactly what 50% vs 100% of the LoRA brings over the no-LoRA baseline.
Dose — what 50% vs 100% brings (top recipe)
λ=0 (no LoRA) — dir 0.263 (raw 0.26)
WER 0.17 · genu 0.10
λ=50% — dir 0.449 (raw 0.45)
WER 0.00 · genu 0.16
λ=100% — dir 0.676 (raw 0.68)
WER 0.23 · genu 0.27
GENERAL: A voice that is markedly bright, positive, cheerful affect.
SCRIPT: (clearly bright, positive, cheerful affect) "Please remember to lock the door before you head out." · temp 1.2 top_p 0.95 top_k 30
Other evolved recipes (100%)
— dir 0.668 (raw 0.67)
WER 0.64 · genu 0.30
A voice that is markedly bright, positive, cheerful affect.
— dir 0.634 (raw 0.63)
WER 0.17 · genu 0.27
A voice that is clearly bright, positive, cheerful affect.
— dir 0.652 (raw 0.65)
WER 0.70 · genu 0.41
A voice that is intensely bright, positive, cheerful affect.
— dir 0.625 (raw 0.63)
WER 0.09 · genu 0.26
A voice that is clearly bright, positive, cheerful affect.
— dir 0.601 (raw 0.60)
WER 0.35 · genu 0.41
A voice that is distinctly bright, positive, cheerful affect.