I know this has been brought up before but there never seems to be a definitive answer.  People have asked if the PLG100VH will give them the same vocoder option on the ES as on the Motif XS.  Generally the reply is that the PLG100VH only gives a vocoder “effect.” However, Yamaha’s own specs, in talking about the vocoder on the XS, say it is a vocoder “effect”, and is listed in the manual of the XS as an insertion effect.  It sounds very much like they are describing exactly what the PLG100VH does.  So is there anyone who has heard both to put to rest the differences, if there are in fact any?

Re: Motif XS Vocoder

There is a huge difference. The PLG100-VH, which does not work in the Motif XS, is a vocal harmony board (thus the VH). It is a harmonizer and can add three voices to your Voice to make as many as four part hamony. You can instruct it by feeding it particular chords that it recognizes… it will then according to the “mode”, add three Voices above you in pitch, below you or around you. So you can be the lead, the bass or the alto or tenor Voice… and the VH boards will add (generate) the other 3 voices qualities.

You can use a “Pitch Correct” function which lets you control three ‘synthesized’ Voices (generated by the PLG100-VH) and it will strictly follow the MIDI note(s) you play - this is the so-called “Vocoder effect” that the PLG100-VH does. (MIDI) Notes you play on the keyboard will determine the pitch of the synthesized vocal sound. Three note poly!

In a strict sense this is not a real vocoder - which works differently. A ‘true’ vocoder allows a microphone input to modify a synth sound. Letting your vocal articulations (from the mic input) shape the result… but the pitch and tone comes strictly from the synth sound you have assigned to the synthesizer - the more harmonics (toward noise) in the sound, the more intelligible it will be. No pitch comes from your voice input, all pitch is determined by the sound of the notes you play on the synthesizer… The Vocoder in the XS is a true vocoder and is therefore 128 note poly!!!

That said, the PLG100-VH sounds more like humans singing, or can.
The Vocoder in the XS sounds, well, like a “traditional” Vocoder.

The PLG100-VH is not a real vocoder because it does not marry your vocal articulations to a sound coming from a synthesizer tone engine. It simply takes your vocal input and forces it to follow pitches from the keybed (MIDI info only) - the actual sound (VOICE) you have selected on the synth has no influence whatever. The VH board totally “synthesizes” the resulting voice.

Tuned just right the PLG100-VH can sound like a group of people singing - that is when it is doing its “Chordal” function - in “Vocoder” mode you can change the gender of the voice from male to female or vice versa… or make it more or less robotic, you can even make yourself sound like Barry White, etc., because it has formant control… remember the “pitch correct” function is used so that the VH created Voice is depending on the MIDI key press for pitch - that makes it sort of “like” a vocoder… but not really.

The Vocoder in the XS (a true vocoder) is what has been described as robot-voices and always has its characteristic tone. And although you have Formant shifting capability - the character of a Vocoder is its own sound.  Less likely to fool someone but very much its own sound… since the actual sound of the synth tone engine is what is being ‘effected"… polyphony is a function of the tone engine of the synth. The Vocoder here (XS) is an Insertion Effect applied to the synth sound.

While the PLG100-VH is an Insertion Effect applied to the microphone (AD) input…

Hope that is clear (or at least is somewhat clearer).