Use your Mac's built-in voices for AI agents

What are macOS voices?

They are the system voices macOS uses for its own spoken content, such as reading selected text aloud. The /usr/bin/say command speaks with any installed voice and can save the result to an audio file instead of playing it, which is what SFCrew does.

More voices, and higher-quality Enhanced and Premium versions, download from Apple under System Settings → Accessibility → Spoken Content → System voice → Manage Voices.

What you can do with macOS voices in SFCrew

The server renders each reply into a short audio clip with say and sends it to whoever is listening, so it plays on your phone or laptop like any other voice, not out of the server's speakers. The voice and calls guide covers each feature.

• Hear replies. Choose Speak this reply on a message, or turn on Read replies aloud in a bot's settings.
• Call a bot with Call at the top of the chat, or have a bot call you when you ask it to.
• Talk instead of typing, using on-device speech recognition. macOS voices don't transcribe, so your words are recognized by your browser, such as Chrome, or by the SFCrew desktop app on a Mac.
• Choose any installed voice. Premium and Enhanced voices are listed first.

When to choose macOS voices

Choose them when you run SFCrew on your own Mac and want bots to speak right away, with nothing to sign up for and nothing to install. Speech is made on the machine running SFCrew, with no vendor involved, then sent to whichever device is listening.

For voices that also transcribe, a self-hosted speech server keeps everything on your own hardware and works on Linux too. Hosted providers sound more natural and need a key: ElevenLabs and Fish Audio clone voices, OpenAI is the simplest, and Cartesia is built for low latency. The voice provider comparison shows all six.

Limits

• SFCrew only offers it when its server process runs directly on macOS. A server in Docker, including Docker Desktop on a Mac and the desktop app's This computer install, runs Linux inside the container, so the option doesn't appear. Linux hosts don't list it either.
• It doesn't transcribe. Hold-to-talk and calls depend on speech recognition in your browser or the desktop app, and voice notes from messaging apps reach bots without a transcript.
• macOS voices sound less natural than the best hosted voices, and there's no voice cloning.
• The voices are whatever is installed on the server's Mac. A newly downloaded voice can take a few minutes to show up.
• On the mobile app, calls can use your phone's own voices if you pick a Device voice in the bot's settings. Otherwise replies use this provider.

How to set it up

This is for someone running SFCrew from source on their own Mac. The self-hosting guide has the full instructions.

1. On the Mac, clone SFCrew, copy .env.example to .env, then run pnpm install, pnpm sandbox:build and pnpm dev. This runs the SFCrew API directly on macOS.
2. To use hold-to-talk and calls, set PHONE_CALLS_ENABLED=true in .env and restart.
3. Optionally download Enhanced or Premium voices under System Settings → Accessibility → Spoken Content → System voice → Manage Voices.
4. In SFCrew, open Settings → Voice and set Provider to Mac voices. There's no key to enter.
5. Pick a Voice and choose Hear a sample.