Today VirSyn released an impressive looking polyphonic pitch-shifting delay effect, Harmony Eight! It may help to think of it as a kind of vocoder, but it is more than that as you can see in the demo video below.
Correction: When I said polyphonic I meant the resulting output, not the input. This was confusing, and in hindsight, dumb of me. The iTunes description now points out that it "needs to detect a single pitch" to work correctly. Thanks to reader Simon for pointing out the new iTunes disclaimer.
Harmony Eight iTunes Description:### Introductory offer for a limited time ###
Up to eight pitch shifted voices are created from vocal input or monophonic instruments.
Position each voice in space ( left and right / front and back )
Modify the voice character from male to female and vice versa.
Pitch shift each voice in the range of +/- one octave with preserving of formants for natural sound.
Applying separate feedback delays on each voice creates complex rhythmical patterns.
• 8 Voice Pitch Shifter with formant correction
• 8 Independent delay lines with optional sync
• Spatial voice positioning
• Parametric Equalizer
• Integrated Compressor/Limiter/Noise Gate
• Ensemble effect
• Reverb effect
• AudioUnit for AUv3 compatible hosts.
• Inter-app audio compatible effect.
• Audiobus 2 compatible with state saving.
• Low latency live usage with mic and headphones.
• Audio recorder