There's an indepth part of the TNT2 tutorial on Vocoding in Logic (Augusts edition), but basically:
- Place an EVOC 20 on a software instrument track.
- Place your vocals on an audio track.
- Set the ouput of the audio track to no output.
- Set the sidechain (in Evoc 20) to the audio track
- record some notes in the EVOC 20.
- Switch the signal to "Voc" and press play!
You can also take a look at these 2 threads :
[b]How to use the EVOC20[/b]
[b]Using the EVOC20 with live vocal[/b]