Qwen Audio 3.1 TTS vs StepAudio 3 TTS

Qwen Audio 3.1 TTS vs StepAudio 3 TTS at a glance

Qwen Audio 3.1 TTS from Alibaba Cloud and StepAudio 3 TTS from StepFun are both in the Audio Generation category, available through the EmpirioLabs API.

Key differences

• Qwen Audio 3.1 TTS is the newer release (Sep 23, 2026); StepAudio 3 TTS was released on Sep 9, 2026.
• Capabilities listed only for Qwen Audio 3.1 TTS: expressive prosody, emotion control, voice tags, low latency, streaming, realtime.
• Capabilities listed only for StepAudio 3 TTS: contextual tts, voice control.

Qwen Audio 3.1 TTS vs StepAudio 3 TTS: specs

Qwen Audio 3.1 TTS vs StepAudio 3 TTS: API pricing

Live rates from the EmpirioLabs catalog for both models. Each rate card always matches what the API charges.

Qwen Audio 3.1 TTS vs StepAudio 3 TTS: API parameters

Request parameters each model lists on EmpirioLabs, with the allowed values or range where one applies. A dash marks a parameter the model does not list.

Qwen Audio 3.1 TTS vs StepAudio 3 TTS: limits and notes

Qwen Audio 3.1 TTS

Voices

• 19 voices: 15 English voices and 4 multilingual voices. Emily, Luna, Eric, and Luca have British accents. Abby, Annie, Ava, Beth, Betty, Cally, Cindy, Donna, Andy, Brian, and David have American accents. The multilingual voices longanhuan_v3.1, longanlingxin_v3.1, longanfengyue_v3.1, and xunanchuan_v3.1 read Chinese, English, and other languages.
• Every voice id ends in _v3.1, for example Emily_v3.1.

Custom voices

• Set voice to custom and pass voice_audio_url, an https URL to 10 to 20 seconds of clear speech from one speaker.
• WAV, MP3, M4A, OGG, WEBM and FLAC are accepted, up to 15 MB. Record in a quiet room, without music or other voices.
• The response includes voice_id and voice_id_expires_at. Pass the voice_id as voice to reuse the voice for 7 days, on POST /v1/audio/speech, POST /v1/audio/speech:stream or the realtime socket, where session.update takes the same fields and session.updated returns the voice_id. Only the account that created it can use it.
• Each account can hold 10 custom voices on this model at a time.
• GET /v1/voices?model=qwen-audio-3-1-tts lists the model's voices, including your custom voices with their ids. Add type=custom to list custom voices alone.
• DELETE /v1/voices/{voice_id}?model=qwen-audio-3-1-tts deletes a custom voice, which frees its place at once.
• In the Playground, set Voice to Custom to use a saved voice again, copy its id, or delete it.
• Creating, listing and deleting custom voices adds no charge.

Delivery direction

• instruction sets emotion, tone, character, pace, and speaking style in natural language, up to 1,000 characters.
• Inline tags inside the text change the delivery from that point, for example [excited] or [whispers], or add a one-time sound such as [laughing] or [sighing]. The full list of tags is on the input parameter.
• SSML input is not supported.

Input limits

• Up to 10,000 characters per request.
• language_hints biases pronunciation for mixed-language text.

Output

• MP3, WAV, PCM, or Opus at 8,000 to 48,000 Hz.
• POST /v1/audio/speech:stream sends audio chunks while the speech is generated.

Realtime

• WEBSOCKET /v1/realtime?model=qwen-audio-3-1-tts takes text while it is still being written and returns audio as it is generated. Send input_text_buffer.append events, then input_text_buffer.commit, or session.finish to end the session.
• Audio arrives in response.audio.delta events: 16-bit PCM at 24,000 Hz by default, or MP3 or Opus. Set the voice, instruction, format and other options with session.update; a change applies from the next segment.
• Text is spoken in segments that end at sentence boundaries, and each segment ends with a response.done event carrying its usage.

Billing

• Input tokens are the text, and output tokens are the generated audio at 12.5 tokens per second.
• Speed and pitch change the length of the rendered audio but not the billed tokens. An instruction that slows the delivery adds output tokens.

StepAudio 3 TTS

Maximum input is 1,000 characters. Content in parentheses is treated as delivery direction and is not spoken. Use instruction for global emotion or style guidance, up to 500 characters. Twelve system voices are available. Recognized languages are Chinese, English, Japanese, Korean, French, and Spanish, with languages other than Chinese and English in preview. Output formats are mp3, wav, flac, opus, and pcm at 8000, 16000, 22050, or 24000 Hz. Wav is returned as a complete file rather than streamed. This model does not support voice_label.

How to call Qwen Audio 3.1 TTS and StepAudio 3 TTS

Qwen Audio 3.1 TTS serves speech through POST /v1/audio/speech and returns playable audio. Send the text to speak as input with the model id qwen-audio-3-1-tts. Both models are called through the same endpoint. Set model to qwen-audio-3-1-tts or stepaudio-3-tts. Get an API key from the EmpirioLabs dashboard.

curl https://api.empiriolabs.ai/v1/audio/speech \
  -H "Authorization: Bearer $EMPIRIOLABS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "qwen-audio-3-1-tts",
    "input": "Welcome to EmpirioLabs. Your build just finished."
  }' \
  --output speech.mp3

Qwen Audio 3.1 TTS vs StepAudio 3 TTS: tests and guides

Prompt tests and comparison runs that cover both models.

Guides Qwen Audio 3.1 TTS Plus vs Qwen Audio 3.1 TTS vs Gemini 2.5 Pro TTS vs StepAudio 3 TTS: one narration We gave Qwen Audio 3.1 TTS Plus, Qwen Audio 3.1 TTS, Gemini 2.5 Pro TTS and StepAudio 3 TTS the same narration and... Guides Qwen Audio 3.1 TTS vs Qwen Audio 3.0 TTS vs Gemini 3.8 Flash TTS vs StepAudio 3 TTS: one script We gave Qwen Audio 3.1 TTS, Qwen Audio 3.0 TTS, Gemini 3.8 Flash TTS and StepAudio 3 TTS the same script and delivery...

Qwen Audio 3.1 TTS vs StepAudio 3 TTS: common questions

What is the difference between Qwen Audio 3.1 TTS and StepAudio 3 TTS?

Qwen Audio 3.1 TTS is the newer release (Sep 23, 2026); StepAudio 3 TTS was released on Sep 9, 2026. Capabilities listed only for Qwen Audio 3.1 TTS: expressive prosody, emotion control, voice tags, low latency, streaming, realtime. Capabilities listed only for StepAudio 3 TTS: contextual tts, voice control. The specs, rate cards, and parameters on this page come from the live EmpirioLabs catalog.

Which is newer, Qwen Audio 3.1 TTS or StepAudio 3 TTS?

Qwen Audio 3.1 TTS is the newer release (Sep 23, 2026); StepAudio 3 TTS was released on Sep 9, 2026.

Which has the lower rate, Qwen Audio 3.1 TTS or StepAudio 3 TTS?

The two models are priced on different units or tiers, so compare the live rate cards on this page. They always match what the API charges.

Can I switch between Qwen Audio 3.1 TTS and StepAudio 3 TTS without rebuilding my integration?

Yes. Both models use POST /v1/audio/speech with the same EmpirioLabs API key, so most integrations switch by changing the model value. Check the parameters table on this page first if you rely on a model-specific parameter.