Models
Speechmatics offers four models for Speech to Text. All four use the same API. The model you choose determines accuracy, how the model handles more than one language, and which features you can configure.
Which models you can use depends on the interaction pattern: pre-recorded and streaming transcription offer Standard, Enhanced, and Melia 1, and agent STT offers Linden 1. For the features each model supports, see Feature availability.
Choose a model
Use Enhanced for the highest accuracy on single-language audio, such as medical, legal, or subtitling work.
Use Standard when throughput or latency matter more than maximum accuracy, such as archival transcription, content indexing, or large-scale captioning.
Use Melia 1 for audio that contains more than one language, including speakers who switch language mid-conversation.
Use Linden 1 for conversational applications that need a turn-based transcript ready to pass to a language model.
Specify a model
Set the model property in your transcription config. If you do not set it, the standard model is used.
This config selects the enhanced model:
{
"type": "transcription",
"transcription_config": {
"model": "enhanced",
"language": "en"
}
}
Linden 1 is the exception: you select it by connecting to an agent STT endpoint rather than by setting model.
Standard
Standard prioritizes throughput. It transcribes a single language, selected with a transcription language pack, and it can detect the language automatically.
Enhanced
Enhanced delivers the highest accuracy of the four models. Like Standard, it transcribes a single selected language and can detect the language automatically.
Enhanced also offers the medical domain, which tunes recognition for healthcare audio. Standard does not.
Melia 1
Melia 1 is a multilingual model. It transcribes audio that contains more than one language, including speakers who switch language mid-conversation, and returns a single continuous transcript. It does not require you to select a language pack, and its accuracy is on par with Standard.
Set "model": "melia-1" and "language": "multi":
{
"type": "transcription",
"transcription_config": {
"model": "melia-1",
"language": "multi"
}
}
Melia 1 does not support the auto language value, which returns an error. Set language to multi.
Melia 1 has no language pack selection. For pre-recorded transcription on SaaS on Cloud it is served from the EU1 and US1 endpoints:
For the full list of endpoints, see Authentication. For the regions and features available with Melia 1, see Feature availability.
Melia 1 for streaming
Streaming with Melia 1 is available on SaaS on Cloud for evaluation and feedback. It is not production-ready and not ready to scale.
Streaming with Melia 1 runs on a dedicated Preview endpoint, wss://preview.rt.speechmatics.com/v2, and returns a language label on every word. On this endpoint Melia 1 transcribes multilingual audio more accurately than Enhanced, and monolingual audio more accurately than Standard.
For the configuration, the supported settings and a runnable example, see Mixed-language transcription.
Linden 1
Linden 1 serves agent STT only. It returns transcripts as complete speaker turns rather than as a word-by-word stream, with turn detection running server-side, which suits applications that hand each turn to a language model.
Linden 1 returns segment-level timings and segment-level partials rather than the word-level equivalents the other three models return.
Linden 1 is available on SaaS on Cloud for evaluation and feedback. It is not production-ready and not ready to scale.
Deprecated: operating_point
The model property replaces the operating_point property. Existing configs that use operating_point continue to transcribe without changes.
On SaaS on Cloud, operating_point is deprecated. It maps to model and accepts the same enhanced and standard values. Use model going forward.