Archive of the former Yahoo!Groups mailing list: MOTM

Any thought about the wonderful tremolo effect that can be heard in Fanfare for the common man at 6:05 and ff with chords and at 6:30 and ff with the solo part? Is there any clone of this circuit or similar? I remember very old Yamaha guitar amplifiers that had a stunning tremolo effect but no idea if there may be a similarity with the GX1 design.
An lfo with a pulse applied to a VCA might probably do the job but that sound has got something magic, almost like a mechanical device. I'd really want to know more about this from someone who may have an idea of what "that thing" really is. Many thanks Enrico Dibennardo (Italy)