# Guitar Domain Expert HTDemucs 6s — Model Configuration
# Fine-tuned from htdemucs_6s (Meta AI) on MoisesDB v0.1

base_model: htdemucs_6s
guitar_stem_index: 4        # Index 4 of the 6-stem output [drums, bass, other, vocals, guitar, piano]

# Audio settings
sample_rate: 44100
channels: 2                 # Stereo input/output

# Inference settings (match fine-tuning receptive field for best results)
segment: 7.8                # seconds — receptive field used during fine-tuning
shifts: 1                   # Overlap-add shifts; higher = cleaner seams, slower inference
split: true
overlap: 0.25               # 25% chunk overlap to smooth boundary artifacts

# Training provenance
fine_tuning:
  base_weights: htdemucs_6s
  dataset: MoisesDB v0.1
  num_songs: 240
  chunk_duration_s: 7.8
  remix_augmentation: true
  remix_probability: 0.80
  gain_range_db: [-6, 6]
  optimizer: Adam
  learning_rate_phase1: 3.0e-4   # Decoder-only warmup
  learning_rate_phase2: 1.0e-4   # Full fine-tune
  gradient_accumulation_steps: 4
  mixed_precision: fp16
  loss: L1 + MultiResolutionSTFT + SI-SDR
  epochs_phase1: 20
  epochs_phase2: 55              # Early stopped at epoch 75 total
  early_stopping_patience: 10