SIL components, and Re: Thru zero FM

[Martin Czech]

:::>I wonder how good the time-dependant modulation works with other >TZVCOs
:::>like the E.N. one. Thats another way of asking if Yamaha style FM is
:::>possible in the analog realm.

click, rrrrrrrr (automatic endless tape starting),
hisssssss, scratch, an automatic voice says: 

Yamaha synths do phase modulation, not FM.
This can be proved very simply:

Modulate one OP with a second, so that a very fast vibrato is audible.
Now tune down the modulator frequency, viola, the frequency modulation  becomes
inaudible. This tells us that the frequency shift depends on modulator
frequency, this is a clear hint that phase modulation is applied.
One c ould also simply look into Yamaha publications, the formulas
also show phase modulation, but this is boring.

Are there other audible differences?

Yes, PM ensures equal sideband amount for any modulator ratio, whereas
FM does not (decreasing with ratio). Therefore PM usually sounds brighter.

If only sine waves are used (this means NO STACKED modulators), and only one
ratio, then PM can be tuned so that it gives exactly the same signal like FM.


;->

m.c.