How to create a "Vocoding" with Nuendo

A VOCODER (from VOice enCODER) works in a very simple way.
It takes a signal called CARRIER, that may be a constant one, or a variable (like the sound of a musical instrument) and modulates it in amplitude, with the electric signal generated by a voice.

The process is very similar to the AM Modulation in a Radio Transmitter, or more precisely, it is similar to a DSB (Double Side Band) or SSB (Single Side Band), because when the voice ceases, also the carrier is not available. Indeed the effect is made by a Balanced Modulator.

In other words, the envelope of the voice, modulate in intensity the Carrier. So that: if you're shouting, the carrier will be porweful, if you are whispering, the carrier will be soft and if you shut-up, the carrier will cease.

If as carrier you use a 50-100 Hz constant signal, the result you have, it is a robotic Voice.
That's very simple principle.

What I did with Nuendo?

I generated a .WAV signal, quite constant, creating the carrier.
A opened a second track and I recorded my voice that tells:"one two three vocoder")

At this point I opened the controls into the carrier's channel and I activated the automation R. So that it reads the position of a digital and automatic potentiometer.

Good. At this point I enhanced the view of the channels in order to see what I was doing

I just manually recreated (copied) the envelope of my voice, into the Potentiometer Control, reproducing quite closely the whole file "one two three vocoder".

At this point, I put in Play the Carrier's channel. As result of the envelope's modulation, "something comprehensible" was reproduced :-) And I got a robotized voice that was telling "one two three vocoder".

Because the carrier is suppressed, it is necessary to extract the extreme high frequency from the Coal Signal in order to rebuild some important consonant: dental consonant, like "s" and "t".
I extracted this spectrum and I added this to the "vocoded" track.

Here the example I created. i know the quality is not excellent, anyhow consider please that I did it manually ;)

http://audioboard.interfree.it/Vocoder_Modulated_Carrier.mp3