Overview
Introduction
Sonna is the open-source, local-first AI voice studio — a free alternative to ElevenLabs and WisprFlow, running entirely on your machine.
What is Sonna?
Sonna is the open-source, local-first AI voice studio. It closes the voice I/O loop in both directions on one machine, with no cloud and no accounts:
- Humans talk — hold a chord anywhere on your machine and your dictation lands as clean text in whatever text field you had focused
- Agents talk back — any MCP-aware agent can call Sonna to speak in one of your cloned voices
- Voices speak for themselves — voice profiles can carry a personality that composes fresh lines or rewrites text before it's spoken
It's the free, local alternative to both ElevenLabs (voice cloning and TTS) and WisprFlow (voice dictation for agents and power users) — covering both sides of the same loop in one app, with a single model directory and LLM shared between input and output.
What's in the app
- Dictation — global hotkey, push-to-talk and toggle modes, auto-paste into the focused field on macOS and Windows (see Dictation)
- Captures tab — paired audio + transcript archive, retranscribe, refine, play-as-voice, promote-to-sample (see Captures)
- Voice cloning — 5 cloning engines covering 23 languages. Zero-shot cloning from a reference sample (see Voice Cloning)
- Preset voices — 50+ curated voices via Kokoro and Qwen CustomVoice for when you don't want to clone (see Preset Voices)
- Voice personalities — optional free-form personality on any profile plus a compose button and persona-rewrite toggle powered by a local LLM (see Voice Personalities)
- Post-processing effects — pitch shift, reverb, delay, chorus, compression, filters (Spotify's Pedalboard)
- Expressive speech — paralinguistic tags like
[laugh]and[sigh]via Chatterbox Turbo; natural-language delivery control via Qwen CustomVoice - Unlimited length — auto-chunking with crossfade for long scripts
- Stories editor — multi-track timeline for conversations and podcasts
- API-first — REST + WebSocket API; MCP server for agent integrations
- Runs everywhere — macOS (MLX/Metal), Windows (CUDA / DirectML), Linux (ROCm / CPU), Intel Arc, Docker
TTS Engines
Seven engines with different strengths, switchable per-generation:
| Engine | Profile Type | Languages | Strengths |
|---|---|---|---|
| Qwen3-TTS (0.6B / 1.7B) | Cloned | 10 | High-quality multilingual cloning |
| Qwen CustomVoice (0.6B / 1.7B) | Preset (9 voices) | 10 | Natural-language delivery control (tone, emotion, pace) |
| LuxTTS | Cloned | English | Lightweight (~1GB VRAM), 48kHz output, 150x realtime on CPU |
| Chatterbox Multilingual | Cloned | 23 | Broadest language coverage |
| Chatterbox Turbo | Cloned | English | Fast 350M model with paralinguistic emotion/sound tags |
| TADA (1B / 3B) | Cloned | 10 | HumeAI speech-language model — 700s+ coherent audio |
| Kokoro | Preset (50 voices) | 9 | 82M parameters, CPU realtime, lowest VRAM of any engine |
STT and local LLM
Sonna also runs a full speech recognition and local LLM stack, shared between dictation, the Captures tab, and per-profile personality modes:
| Layer | Models |
|---|---|
| STT | Whisper Base / Small / Medium / Large / Turbo (PyTorch or MLX) |
| LLM | Qwen3 0.6B / 1.7B / 4B (refinement + per-profile compose / persona-rewrite) |
No cloud fallback, no bring-your-own-API-key. Local is the product.
GPU Support
| Platform | Backend | Notes |
|---|---|---|
| macOS (Apple Silicon) | MLX (Metal) | 4-5x faster via Neural Engine |
| Windows / Linux (NVIDIA) | PyTorch (CUDA) | Auto-downloads CUDA binary from within the app |
| Linux (AMD) | PyTorch (ROCm) | Auto-configures HSA_OVERRIDE_GFX_VERSION |
| Windows (any GPU) | DirectML | Universal Windows GPU support |
| Intel Arc | IPEX/XPU | Intel discrete GPU acceleration |
| Any | CPU | Works everywhere, just slower |
Use Cases
- Dictation for humans and agents — speak instead of type, in any app
- Agent voice output — any MCP-aware agent can speak in a cloned voice
- Game development — generate dynamic dialogue for characters
- Content creation — podcasts, video voiceovers, audiobooks
- Accessibility — speech-to-text for any field, TTS with a voice you own
- Voice assistants — custom voice interfaces without a cloud bill
- Production pipelines — automate voice workflows via the REST API
Tech Stack
| Layer | Technology |
|---|---|
| Desktop App | Tauri (Rust) |
| Frontend | React, TypeScript, Tailwind CSS |
| State | Zustand, React Query |
| Backend | FastAPI (Python) |
| TTS Engines | Qwen3-TTS, Qwen CustomVoice, LuxTTS, Chatterbox, Chatterbox Turbo, TADA, Kokoro |
| STT | Whisper / Whisper Turbo (PyTorch or MLX) |
| Local LLM | Qwen3 0.6B / 1.7B / 4B (MLX or PyTorch) |
| Effects | Pedalboard (Spotify) |
| Inference | MLX (Apple Silicon) / PyTorch (CUDA/ROCm/XPU/CPU) |
| Database | SQLite |
| Audio | WaveSurfer.js, librosa |