Implementation:Speechbrain Speechbrain Train Wav2Vec2 SSL

Knowledge Sources	SpeechBrain
Domains	ASR, Training
Last Updated	2026-02-09 00:00 GMT

Overview

Concrete tool for self-supervised pre-training of a wav2vec 2.0 model on the CommonVoice dataset provided by the SpeechBrain library.

Description

This recipe defines the W2VBrain class (subclass of sb.core.Brain) for wav2vec 2.0 self-supervised pre-training. It wraps the HuggingFace Transformers implementation of wav2vec 2.0 within the SpeechBrain framework. The model uses contrastive learning to learn speech representations from unlabeled audio. During training, the forward pass returns only the contrastive loss from the HuggingFace model; during evaluation, cosine similarity between projected states and quantized states is computed as an accuracy metric.

Usage

Use this recipe to pre-train a wav2vec 2.0 model on CommonVoice (or any dataset with a JSON/CSV manifest). The resulting model can then be used as a pre-trained encoder for downstream ASR tasks.

Code Reference

Source Location

• Repository: SpeechBrain
• File: recipes/CommonVoice/self-supervised-learning/wav2vec2/train_hf_wav2vec2.py

Signature

class W2VBrain(sb.core.Brain):
    def compute_forward(self, batch, stage):
        """Forward computations from the waveform batches to the w2v2 loss."""
        ...
    def compute_objectives(self, predictions, batch, stage):
        """Computes the loss (CTC+NLL) given predictions and targets."""
        ...

Import

# Run as recipe script
python recipes/CommonVoice/self-supervised-learning/wav2vec2/train_hf_wav2vec2.py hparams/hyperparams.yaml --data_folder /path/to/commonvoice

I/O Contract

Inputs

Name	Type	Required	Description
batch.sig	torch.Tensor	Yes	Input waveform signal

Outputs

Name	Type	Description
loss	torch.Tensor	Contrastive loss from wav2vec 2.0
out	Wav2Vec2ForPreTrainingOutput	Model output including projected and quantized states (eval only)
mask	torch.Tensor	Mask time indices used for contrastive loss (eval only)

Usage Examples

python train_hf_wav2vec2.py hparams/hyperparams.yaml --data_folder /path/to/CommonVoice

Related Pages

• Principle:Speechbrain_Speechbrain_Transformer_ASR_Training