Namadgi/MultiDecoderDPRNN-finetuned

Multi-Decoder DPRNN — Fine-Tuned for 1–5 Speaker Separation

Fine-tuned version of MultiDecoderDPRNN for variable speaker count (1–5) speech separation.

What changed?

The original pre-trained model supports 2–5 speakers and always outputs 5 active sources regardless of actual speaker count (~22% speaker count accuracy). Our fine-tuning teaches the model to:

• Correctly identify the number of speakers (88% accuracy)
• Output silence on unused channels
• Support single-speaker scenarios (new 1-speaker decoder)

Checkpoints

Checkpoint	Architecture	SI-SDR	SI-SDRi	SDR	Spk Acc	File
Rys (best)	n_srcs=[1,2,3,4,5]	+7.33 dB	+10.01 dB	+7.32 dB	88.0%	weights/dprnn_rys_weights.pt
Zhaksh	n_srcs=[2,3,4,5]	+3.24 dB	+5.92 dB	+3.24 dB	50.0%	weights/dprnn_zhaksh_weights.pt
Original (baseline)	n_srcs=[2,3,4,5]	-1.29 dB	+1.39 dB	-1.29 dB	22.0%	—

SI-SDRi by Speaker Count

N	Original	Rys	Zhaksh
1	-9.17 dB	+8.86 dB	-7.47 dB
2	+4.07 dB	+11.98 dB	+11.58 dB
3	+2.46 dB	+10.00 dB	+9.78 dB
4	+4.56 dB	+9.65 dB	+7.78 dB
5	+5.05 dB	+9.56 dB	+7.94 dB

Usage

import sys, torch
sys.path.insert(0, "asteroid/egs/wsj0-mix-var/Multi-Decoder-DPRNN")
from model import MultiDecoderDPRNN
from huggingface_hub import hf_hub_download

# Load base architecture with extended speaker count
pretrained = MultiDecoderDPRNN.from_pretrained("JunzheJosephZhu/MultiDecoderDPRNN")
fb = pretrained.encoder.filterbank
cfg = dict(
    bn_chan=pretrained.masker.bn_chan, hid_size=pretrained.masker.hid_size,
    chunk_size=pretrained.masker.chunk_size, hop_size=pretrained.masker.hop_size,
    n_repeats=pretrained.masker.n_repeats, norm_type=pretrained.masker.norm_type,
    bidirectional=pretrained.masker.bidirectional, rnn_type=pretrained.masker.rnn_type,
    num_layers=pretrained.masker.num_layers, dropout=pretrained.masker.dropout,
    n_filters=fb.n_feats_out, kernel_size=fb.kernel_size,
    stride=fb.stride, sample_rate=8000,
)

model = MultiDecoderDPRNN(n_srcs=[1, 2, 3, 4, 5], **cfg)
weights = hf_hub_download("Namadgi/MultiDecoderDPRNN-finetuned", "weights/dprnn_rys_weights.pt")
model.load_state_dict(torch.load(weights, map_location="cpu"))
model.eval()

# Inference
mix = torch.randn(1, 32000)  # [batch, time] at 8kHz
reconstructed, selector = model(mix, ground_truth=[3])  # 3 speakers
# reconstructed: [1, n_stages, max_spks, T]
# selector: [1, n_stages, n_decoders]

Training Details

• Base model: JunzheJosephZhu/MultiDecoderDPRNN
• Dataset: 10,000 synthetic mixtures (LibriSpeech train-clean-100 + WHAM! noise), 1–5 speakers
• Evaluation: 50 samples from held-out CV set (LibriSpeech dev-clean + WHAM! cv)
• Sample rate: 8 kHz
• Loss: Multi-stage PIT SI-SDR + Cross-entropy selector loss

Authors

• Rys (@RysNamadgi)
• Zhaksh

Part of the Namadgi research group.