Widisoft has released an Audio Unit version of the WIDI Audio To MIDI plug-in.

Based on the WIDI Audio To MIDI VST, WIDI AU includes chord recognition feature and a built-in MIDI recorder. It allows you to use arbitrary MIDI Output devices, including virtual MIDI devices for routing MIDI back to the host.

WIDI Audio To MIDI AU costs $63.90 until 1st July, 2006, when the price will rise to $79.90. A cross-grade from the VST version costs $23.90. A demo version is available.