Vocoder Au, help with talkbox Options

[adp10390]

I recently downloaded a high-resolution vocoder as part of a package of AUs called mda. Here is the text from the readme:

mda TalkBox
-----------
This plug-in is a high resolution vocoder, designed for a natural rather than an
electronic sound. The Quality parameter is equivalent to the number of bands in a
normal "channel" vocoder. The plug-in expects a modulator signal (usually voice or
drums) in the main input bus and a carrier (usually synth or guitar) in the second
input bus, but the Input Swap parameter can be used to reverse this.

*** Please note that Talkbox is a multi-input-bus plug-in and not all AU hosts
support plug-ins with more than 1 input bus. Currently Logic and Live are known to
support this. In Logic, you can route the second input bus in via the plug-in's
"sidechain" menu selection. In Live, you will see the second input bus appear as an
audio output destination on tracks. ***

For a typical talkbox sound, try inputting a synth sound with oscillator sync (at a
fixed slave frequency, between 12 and 20 semitones above the master) with the master
oscillator volume turned down, and vibrato added with the mod wheel or aftertouch.
Alternatively, for a natural vocal sound use a low-pass filtered saw wave with
random pitch modulation, plus high-pass filtered white noise.

Now, I tried recording my voice and a synth, sending them to Bus1, and placing the talkbox effect on bus1, and i could hear no change in output, whether the effect was on or off, etc. any suggestions would be very much appreciated.

[adp10390]

Thanks! but... what is a sidechain?