Jonathan Schmid-Burgk has released VisualVox VST, a free intonation correction VST plug-in.
- shift notes of a voice recording to perfect intonation
- fit a voice recording into rythm by stretching, cutting and moving parts of it
- fit a voice recording to another key with minimal pitch changes
- produce a perfect vibrato
- visualize how right or wrong you are singing
- create artificial polyphony from single voice recording
- draw frequency curves freely with your mouse
- let the VST plugin improve intonation automatically
VisualVox is still in a developmental stage and Jonathan welcomes suggestions and comments here.