john frusciante - shadows collide with people voice effect

[olfunk]

hey
i just listened to the song "the slaughter" off john frusciante's album shadows collide with people, and at the beginning i was just wondering if anyone knew what effect is on the voice. it sounds like some has played the melody on a synth, and then his voice has been fed into the synth somehow. i cant explain it.
thanks

 

[Theros]

Vocoder perhaps... never heard the song tho...