Exponential FM synthesis

Studiowaves

Modulating one sine wave with another with linear gain changes in the modulators amplitude verses exponential gain changes is the only thing that makes sense regarding this discussion. I don't know where your going with this but thats what I did with the envelope generators in FM12. It's in the UL, The envelope generators are linear and I changed the linear modulation change to an exponential gain change. But only because we sense decibels which are logarithms of translations. From linear to log. Pitch is exponential, Consider the formula, 1 semitone is 2^[1/12] times a note. It's how the equal temperament is formed. Each semitone is a multiple or division of the adjacent semitone. Not an addition fo the same number. So what is your point, not everything you said make sense. Reword this for me. Thanks

colB

https://community.native-instruments.com/discussion/comment/197381#Comment_197381

One simple trick that NI don't want you to know about:

RTFM

https://www.native-instruments.com/fileadmin/ni_media/downloads/manuals/REAKTOR_BLOCKS_Manual_English_072220.pdf

KoaN

https://community.native-instruments.com/discussion/comment/197381#Comment_197381

If you don't want to mess around with blocks the same author did a 8 voice poly version ensemble of this but only 2 types of FM,Lin and Exp.

https://www.native-instruments.com/en/reaktor-community/reaktor-user-library/entry/show/10233/

ncg777

https://community.native-instruments.com/discussion/comment/197499#Comment_197499

I'll sure be using that!

Studiowaves

https://community.native-instruments.com/discussion/comment/198638#Comment_198638

I think your saying is you want to adjust the volume of the modulator in a logarithmic fashion. In reality you should if you wish for the overtones generated by fm to change in volume like a good "decibel per travel distance" fader. I think you'll find out the envelope generators in reaktor are linear and not logarithmic. They curve they produce in volume sounds logarithmic. As in slow to start and gets faster and faster as the levels fall. It looks linear but doesn't sound linear. It's an easy fix though, just run it thru the converter that converts a linear line to a decibel curve. Look up VCA and dive deeper, you'll see the log converter. It's 1.19 or something. I basically allows you to make a dial go some db range like +10 down to -60. The vca will change the volume to sound like an even change in volume as you rotate the dial. So basically feed the output of the vca into the fm modulator or carrier and you'll get what your asking for.

ncg777

What I was saying? I'll reiterate…

Given I is index of modulation, fₐ is carrier frequency, fₘ is modulator frequency then fm is defined by:

x(t) = Aₐ sin(2πfₐt + I sin(2πfₘt))

but I think it should be:

x(t) = Aₐ sin(2π(fₐ*(2.0^(I sin(2πfₘt))))*t)

The frequency of the output signal should vary like notes, 2^(i/12).

That is all I am saying.

After testing Sirius-8 a little, it really sounds awesome, but I prefer my modified FM4 (exp). Here's an updated version with indexes of modulation going up to a maximum of 3 octaves and being scaled, I hope correctly.

FM4 (exp).ens

ncg777

Does anyone know how would I proceed to release my modified version somewhere? I think it's pretty much ready now; I adjusted the modulation parameters to values between 0 and 12, with steps of 0.05 and it seems rather precise enough.

FM4 (exp).ens

ncg777

Wait a minute… I got the parameters wrong again… lol….

ncg777

Une unit of modulation means 1 octave; a twelfth of one unit is a semitone. So the steps should be 1/12… upper limit I set to 3…

FM4 (exp).ens