Faster Kokoro on Windows and a Signed Installer

When we shipped MLX-backed Kokoro on Mac, Windows still used the portable Transformers.js path. That kept things consistent across platforms, but it left a clear gap: Mac got a much faster local engine, and Windows did not.

That gap is closed. Windows now has a faster on-device Kokoro runtime too and while we were at it, the Windows installer is now signed with a valid certificate, so installing WithAudio feels like installing any other trusted desktop app.

KokoroSharp: Faster TTS on Windows

The new engine is using KokoroSharp, a C# / ONNX inference stack for Kokoro TTS. In WithAudio it runs on-device as the recommended local runtime for Kokoro on Windows.

Simple tests show roughly 2× TTS speed and less resource usage (less memory and CPU) when WithAudio uses KokoroSharp instead of the previous path. Everyday reading feels snappier; long exports and full-document audio jobs finish sooner without leaning as hard on the machine.

Nothing about the privacy model changes. Synthesis still happens locally. Your documents and audio stay on your device.

For setup pick the preferred runtime and downloading WithAudio Local Windows KokoroSharp. See the docs: Use Kokoro with KokoroSharp on Windows.

A properly signed Windows installer

The Windows installer executable is now signed by a valid certificate. That means fewer scary “unknown publisher” warnings, a clearer trust path on first install, and a smoother experience for anyone deploying WithAudio on a work machine or a carefully locked-down PC.

Try it

Update to the latest Windows build of WithAudio from desktop.with.audio. Open Settings → Engines, find the Kokoro card, and choose WithAudio Local Windows KokoroSharp as the preferred runtime (download it first if needed). New audio will use the faster engine.

Questions or rough edges on a particular machine? Email [email protected] Windows feedback is especially welcome as this path rolls out.