Qwen Audio 3.1 ASR Stream API

About Qwen Audio 3.1 ASR Stream

Live transcription over a socket, streaming partial words while the speaker talks and a settled sentence at each pause, priced per token.

Stream 16 kHz pcm16 audio over the socket. Partial results arrive while the speaker is talking.

Also known as Qwen Audio ASR Stream, Alibaba Cloud Qwen Audio 3.1 ASR Stream

Qwen Audio 3.1 ASR Stream specs

Model ID

qwen-audio-3-1-asr-stream

Author

Alibaba Cloud

Category

Transcription

Released

-

Input

Audio

Output

Text

Region

Singapore

Endpoints

WEBSOCKET/v1/realtime

Alternate model IDs

qwen-audio-3.1-asr-streamalibaba/qwen-audio-3-1-asr-stream

Qwen Audio 3.1 ASR Stream API pricing

Live pay-as-you-go rates from the EmpirioLabs catalog. You are billed only for what you use, with no monthly minimum.

How to call the Qwen Audio 3.1 ASR Stream API

Qwen Audio 3.1 ASR Stream transcribes a live audio stream over a WebSocket at wss://api.empiriolabs.ai/v1/realtime?model=qwen-audio-3-1-asr-stream, not over the HTTP endpoints. Connect with the model id qwen-audio-3-1-asr-stream and send your EmpirioLabs API key as an Authorization: Bearer header on the handshake. Append base64 16-bit PCM audio and read transcript events back while the speaker is still talking. A browser cannot set headers on a WebSocket, so open this connection from your server and relay audio to the browser over your own socket. Get an API key from the EmpirioLabs dashboard.

import asyncio, json, os, websockets

async def main():
    async with websockets.connect(
        "wss://api.empiriolabs.ai/v1/realtime?model=qwen-audio-3-1-asr-stream",
        additional_headers=[
            ("Authorization", f"Bearer {os.environ['EMPIRIOLABS_API_KEY']}"),
        ],
        max_size=None,
    ) as ws:
        print(json.loads(await ws.recv())["type"])  # session.created

        import base64

        # 16-bit PCM microphone audio, base64 encoded, in small chunks.
        for chunk in read_microphone_chunks():
            await ws.send(json.dumps({
                "type": "input_audio_buffer.append",
                "audio": base64.b64encode(chunk).decode(),
            }))

        await ws.send(json.dumps({"type": "input_audio_buffer.commit"}))

        async for raw in ws:
            event = json.loads(raw)
            if event["type"].endswith("input_audio_transcription.delta"):
                # "text" is settled transcript; "stash" is still in progress.
                if event.get("text"):
                    print(event["text"], end="", flush=True)

asyncio.run(main())

Qwen Audio 3.1 ASR Stream API parameters

Request parameters supported by the Qwen Audio 3.1 ASR Stream API on EmpirioLabs. Defaults apply when a field is omitted.

Good to know

Connecting

Live transcription over a WebSocket at wss://api.empiriolabs.ai/v1/realtime?model=qwen-audio-3-1-asr-stream, authenticated with the ordinary Authorization Bearer header.

Sending audio

Stream 16 kHz mono pcm16 audio with input_audio_buffer.append. Voice activity detection decides where each sentence ends, so there is no commit to send.

What comes back

conversation.item.input_audio_transcription.delta events carry the sentence so far while the speaker is still talking, and conversation.item.input_audio_transcription.completed carries the settled sentence at each pause.

Billing

Input and output tokens are priced per 1M, and each completed sentence is billed on its own from the usage the model reports.

Qwen Audio 3.1 ASR Stream API: common questions

How much does the Qwen Audio 3.1 ASR Stream API cost?

On EmpirioLabs, Qwen Audio 3.1 ASR Stream is billed pay as you go: Input $1.86 per 1M audio input tokens; Output $1.40 per 1M generated tokens. The live rate card on this page always matches what the API charges.

Which endpoint does Qwen Audio 3.1 ASR Stream use?

Qwen Audio 3.1 ASR Stream is served through WEBSOCKET /v1/realtime on api.empiriolabs.ai with standard bearer-token authentication.

Can I try Qwen Audio 3.1 ASR Stream in the browser before integrating?

Open the EmpirioLabs playground and press Start session to try it in your browser. Qwen Audio 3.1 ASR Stream runs over a WebSocket rather than a request and response, so to build with it start from the realtime voice quickstart. Connect from your server with your EmpirioLabs API key and the model id qwen-audio-3-1-asr-stream, then stream audio in both directions.

How do I get a Qwen Audio 3.1 ASR Stream API key?

Create an EmpirioLabs account, then generate a key under API Keys in the dashboard. Billing is pay-as-you-go credits, so you only pay for the requests you make.