Transcribe English audio with Parakeet CTC

When you know the audio is English and latency matters, Parakeet CTC is faster than TDT. The trade is that CTC is English-only; Parakeet CTC rejects non-English audio rather than mistranslating it.

CTC is the English-only sibling of TDT. The model file is smaller and the inference path is shorter, so transcribe returns a few hundred milliseconds sooner.

The editor prefills the model load (Parakeet CTC with modelType: "parakeet-transcription"). The new piece is the transcribe call.

CTC is the English-only TDT variant, using the same call signature and options with a different modelId. The transcribe call we'd make would look like:

const text = await transcribe({
  modelId,
  audioChunk: "./examples/qvac/transcription/input/sample-16khz.wav",
});
console.log(text);

The call signature and the constants are the only differences from TDT.

Note: CTC is also the right Parakeet variant for the transcribeStream duplex session when the audio is English. The next lesson covers diarization with Sortformer.