6.1 override_style Parameter
The core system modification is the override_style parameter added to Seed-VC’s
convert_voice_with_streaming() method. The original implementation extracts style embedding from the target
reference audio internally. Our modification allows bypassing this extraction with an arbitrary style vector.
Changes in modules/v2/vc_wrapper.py (3 lines):
This is the critical architectural change that enables our research — we can inject any 192-dim vector into the
diffusion conditioning pipeline.
6.2 ΔV Injection
The app.py:run_vc_conversion() function orchestrates the injection:
Two outputs are produced: – Standard: Normal Seed-VC conversion (no override) – Perceived: Same conversion
with target_style = V_raw + ΔV × intensity
The intensity slider (range 0.0–2.0) allows continuous control over the ΔV effect.
6.3 Lazy Loading
The Seed-VC model (552M parameters) requires significant memory and load time. Lazy loading defers model
initialization to the first conversion request:
•
Module-level wrapper cache with ensure_vc_wrapper()
•
Model loads once, reused across all subsequent conversions
•
Startup time reduced from ~20 seconds to near-instant
6.4 Streaming Fix
Seed-VC’s streaming mode (stream_output=True) produces audio chunks via a Python generator. The original
implementation used stream_output=False, which caused an UnboundLocalError because the generator was
initialized but never consumed. Changing the parameter to True fixed this bug.
6.5 MPS AR Cache
Apple Silicon (MPS) requires explicit KV-cache preallocation for the AR transformer:
This pre-allocation is performed once during model initialization and reused across all conversions.
6.6 Gradio User Interface
The system provides a three-tab Gradio web interface with a New Wave Brutalist design theme (black background,
neon green accents, monospace typography):
VC Tab: – Source audio and reference audio upload – XY scatter plot of top-2 ΔV dimensions – ΔV toggle (ACTIVE/
INACTIVE) – Intensity slider (0.0–2.0) – Real-time metrics: ‖V_raw‖, ‖V_perceived‖, ‖ΔV‖, cosine similarity – Two
audio outputs with download: STANDARD and PERCEIVED – Progress bar per processing stage
VIS Tab: – Frequency response plot of the skull resonance filter (log scale) – 192-dimensional bar chart of ΔV (green
= positive, magenta = negative) – Audio spectrogram with black/neon-green colorscale
INFO Tab: – Documentation of problem, method, and technology stack – Clinical application description – Academic
references
