An Exploration Of Automated Speech Recognition


September 25th, 2021

54 mins 1 sec

Your Hosts

About this Episode


The overwhelming growth of smartphones, smart speakers, and spoken word content has corresponded with increasingly sophisticated machine learning models for recognizing speech content in audio data. Dylan Fox founded Assembly to provide access to the most advanced automated speech recognition models for developers to incorporate into their own products. In this episode he gives an overview of the current state of the art for automated speech recognition, the varying requirements for accuracy and speed of models depending on the context in which they are used, and what is required to build a special purpose model for your own ASR applications.


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  • Your host as usual is Tobias Macey and today I’m interviewing Dylan Fox about the challenges of training and deploying large models for automated speech recognition


  • Introductions
  • How did you get introduced to Python?
  • What is involved in building an ASR model?
    • How does the complexity/difficulty compare to models for other data formats? (e.g. computer vision, NLP, NER, etc.)
  • How have ASR models changed over the last 5, 10, 15 years?
  • What are some other categories of ML applications that work with audio data?
    • How does the level of complexity compare to ASR applications?
  • What is the typical size of an ASR model that you are deploying at Assembly?
    • What are the factors that contribute to the overall size of a given model?
  • How does accuracy compare with model size?
  • How does the size of a model contribute to the overall challenge of deploying/monitoring/scaling it in a production environment?
  • How can startups effectively manage the time/cost that comes with training large models?
  • What are some techniques that you use/attributes that you focus on for feature definitions in the source audio data?
  • Can you describe the lifecycle stages of an ASR model at Assembly?
  • What are the aspects of ASR which are still intractable or impractical to productionize?
  • What are the most interesting, innovative, or unexpected ways that you have seen ASR technology used?
  • What are the most interesting, unexpected, or challenging lessons that you have learned while working on ASR?
  • What are the trends in research or industry that you are keeping an eye on?

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The intro and outro music is from Requiem for a Fish The Freak Fandango Orchestra / CC BY-SA