Reason 4.0 Vocoder

Anyone care to explain how one can achieve this using Reason? I figured out how to setup a vocoder track but I can't seem to get the vocals to stay in sync. Whenever I'm playing a chord I get the modulated vocoder sound that I want but the vocals aren't synced or do not play together. Since the sample is pitched across the keyboard some will play slightly slower/faster than the other. How can I make it to where my vocals are in sync when I play a chord?

Heres a video of what I'm talking about for an example.

http://youtube.com/watch?v=a_Rby38vRWU&watch_response

.... that's not the way to do it .

You play a chord using Subtractor. This one goes into the Carrier input of the vocoder. You play the vocals using NNXT or NN19; you only play a single note, and that goes into the Modulator input.

A sampler is much like a digital tape recorder; speed up the tape and you'll get a munchkin effect. The tempo can't help but change.

The solution for this is called timestretching but is not related to vocoders at all. Timestretching fills up the gaps or cuts them out; and both regular samplers in Reason don't timestretch. Dr Rex won't do it either, but that's because of the sampling material used.

When a drummer plays a rhythm, all he has to do to go slower is leave bigger gaps between playing drums. Since drums are short, leaving those gaps isn't that much of a problem; you sort of "lock" the drums to when they're played and then leave more of a silence between them, which allows you to slow down (or speed up) drums with not much noticeable effect.

So, since neither sampler will stretch, you can either cut up the vocal in very, very short bits and play them back in order, or use the above (don't play chords with the vocals, do this with the carrier). If you don't have any hands free to do this, let the sequencer play the vocal bits; there's no other way to do it since Reason doesn't do audio tracks.

If you're using NN-XT just turn the keyboard tracking knob to 0. That way the sample will play at the base pitch regardless of which key you play. Also set the NN_XT polyphony to 1.