Hi
I just bought Pigments and this teaches me a lot about sound design and I am happy with my purchase
However, I have a question about the implementation of FM in Pigments 5.
Here are two screenshots of the spectrogram of a FM modulation of a sine wave at ratio 1, with FM amount set to middle. The first is C3 the second is C5
They do not have the same profile, whereas my understanding of the FM theory is that they should. One has many more partials than the other: the C5 is lacking high frequencies.
When I try the same experiment on the DX7, I have the same profile in C3 and C5.
I am just discovering Pigments and FM modulation and am addressing this from an engineer background, because I like to understand what is happening under the hood. I also have the impression that this is skewing the rendition of the timbre depending on the note keyed, which seems to me a bad thing, which should not happen.
So my question is why this is happening, and moreover, why nobody seems to care (since we are at version 5 of pigments)
Thanks
[EDIT: Hmm, I found the answer myself. Actually it’s because what is commonly called FM modulation is not frequency modulation but phase modulation (including on the DX7). So when I do the same experiment with Pigments phase modulation, everything is OK , sonogram profile is conserved all over the keyboard. As it should. Arturia is only using the right terminology, and I was confused ]