Scaler Music has released Scaler Detector, a key and chord detection plugin (VST/AU/AAX) and standalone app for Mac and PC. Scaler Detector is free to owners of Scaler 3 and otherwise available for the regular price of $9. Here's what they have to say about it...
Scaler Detector identifies chords from MIDI or audio when the Detect button is active, and derives a list of musical scales that match them, ranked by goodness of fit.
A user can play back any chord (one detected or a member of a scale) by clicking it or assigning it to a single note using the Bind Keys function. Voice Grouping is also available for bringing all chords' notes into a similar range.
Any chord (or multiple chords) can be dragged out of Scaler Detector for use elsewhere.
Pricing and Availability:
$9 or free for Scaler 3 users
More information: