Give yourapplication a voice.
Turn text into speech and speech into text. Run locally. Embed it in your application.
Your speech workspace.
Choose a voice, edit your text and listen to the result.

Text to speech (TTS)
Write it. Hear it.
Read application messages, dialogue prompts and SSML with local speech models. Supported engines can deliver audio before the full utterance is complete.
- Decoder, text-chunk or autoregressive streaming, depending on the model
- Languages and voices follow the installed model packages
- SSML preparation, reading rules, pauses and speaking speed
SSML support
Shape how your words are spoken.
Use SSML to control pauses, speaking speed and how numbers are read. Supported tags and languages depend on the selected model.
- Add timed pauses between sentences with break
- Change the speed of a passage with prosody
- Choose how numbers, dates and letters are read with say-as
Give your application a voice with Sintel SES
Turn text into speech, and speech into text
Run speech models on your own server, with your own applications and telephony workflows.
Speech to text (STT)
Speak. See it.
Transcribe recordings and live audio on your server. Mira and Nemo support native streaming; Duyum supports file transcription and revisable text previews.
- Transcribe WAV recordings and recorded microphone audio
- Native live decoding with streaming-capable engines
- Mix, left, right or separate channel processing in the speech tools
Voice gallery
Choose the voice that fits.
A selection from your installed voices. Sign in to explore the complete library and read your own text.
Only installed models and their reported languages are shown. Available voices and capabilities depend on the selected model and package.
Architecture \u0026 deployment
Run speech on your infrastructure.
Embed speech models in your application or connect through an API, telephony integration or local service. Generate speech and transcribe audio on the CPU, with no GPU required.
Speech inference runs on your server. Install model packages once, then process audio locally. Downloading models may require an internet connection.
Interactive studio
Experience SintelSES in your browser.
A voice library, text composer and transcription workspace await after sign-in. The preview below introduces the available tools.
Model-aware controls
- Choose a supported reading language
- Select a voice from the installed catalog
- Adjust speed when the model supports it
- Listen, inspect the waveform and download WAV
Installed engines
Model and capability comparison.
Only installed models and their reported languages are shown. Available voices and capabilities depend on the selected model and package.
| Model | Task | Languages | Sample rate | Capabilities |
|---|---|---|---|---|
| Ahen | TTS | 48 kHz | Local speech synthesis using an installed model. | |
| Mira | ASR | 16 kHz | Native streaming transcription for live audio. |
Measured locally · docs/BENCHMARKS.md
Performance, with context.
A recorded Duru 3.1 (Vocos-ft) streaming measurement. These are development-machine results, not a latency guarantee.
First PCM
10.96 msDuru · StreamGeneration time
45.02 msDuru · StreamReal-time factor
0.01119Duru · StreamAudio duration
4.022 sDuru · StreamApple M4 Max · macOS arm64 · ONNX Runtime 1.30.0 CPU · 4 threads · 1 warm-up + 3-iteration average · October 17, 2026
Studio voice, Turkish, 24 kHz; warm Stream with a non-blocking callback, speed=1, seed=42. Model opening, network, WAV writing and playback are excluded. First PCM is not audible latency or network RTT.
Built for developers
From your first import to your first call.
Use the Go SDK in your application or connect to the local service. The examples use the current SDK and CLI interfaces.
Install your models
Prepare the runtime and the language/model packages for your target machine.
Start the local engine
Open a model in Go or run the SintelSES service on your host.
Connect your application
Choose the SDK, Unix socket or MRCPv2 integration. The SDK currently uses a local module replace.
OpenAI API
Use the documented TTS and ASR endpoints with OpenAI clients. See the API guide for supported audio formats.