The Yamaha AN1x Synthesizer mailing list

Tome wrote:

>>
So please can someone explain what´s the 
difference between the X-Mod of the AN200/PLG150AN and the FM inside 
the AN1x?
<<

Ok, I'll try.

The AN engine algorithm provides two ways of modulating one oscillator
with another. 

1) You can perform FM, where the wave of one oscillator (called the
modulator) periodically changes the pitch or frequency of another
oscillator (called the carrier). In both the AN1x and PLG150AN, VCO1 is
the carrier and we have a whole bunch of sources for the modulator
(including VCO2). Furthermore VCO1 can be split into a pair of
oscillators and you can select whether either one or both of these use
FM.

2) You can perform Sync modulation. In this case the wave of one
oscillator (master) is used to reset the wave of a second oscillator
(slave). If the two oscillators are operating at different frequencies,
this has the effect of chopping up the output into complex waveforms.
(Generally the master determines the output pitch and the slave
determines the timbre/tone). In the An1x we can use this type of
modulation only 'within' VCO1. i.e. VCO1 actually contains two
oscillators that can be arranged in a master/slave arrangement. However
in the PLG150AN, you can also choose VCO2 as a master to provide sync
modulation to VCO1. This allows for much more complex cross modulation
between the two VCOs than standard FM. Therefore the PLG150AN (and
AN200) are capable of producing more complex sounds than the AN1x.  

I hope that clarifies the situation ;-)


Regards

Gary Gregson

Email:gary@...
http://www.yme.co.uk/yme