Transformer-based Acoustic Modeling for Hybrid Speech Recognition

May 4, 2020


We propose and evaluate transformer-based acoustic models (AMs) for hybrid speech recognition. Several modeling choices are discussed in this work, including various positional embedding methods and an iterated loss to enable training deep transformers. We also present a preliminary study of using limited right context in transformer models, which makes it possible for streaming applications. We demonstrate that on the widely used Librispeech benchmark, our transformer-based AM outperforms the best published hybrid result by 19% to 26% relative when the standard n-gram language model (LM) is used. Combined with neural network LM for rescoring, our proposed approach achieves state-of-the-art results on Librispeech. Our findings are also confirmed on a much larger internal dataset.

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Written by

Yongqiang Wang

Abdelrahman Mohamed

Duc Le

Chunxi Liu

Alex Xiao

Jay Mahadeokar

Hongzhao Huang

Andros Tjandra

Xiaohui Zhang

Frank Zhang

Christian FuegenGeoffrey Zweig

Michael L. Seltzer


International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

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