FM synthesis

General feedback, questions and feature requests.
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aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

FM synthesis

Post by aldonecheeba »

hi all

i've been trying to figure out the FM controller, but no positive results


what bloc should by before it, of after ? can somebody post a patch to show that?

thanks
audiojunkie
Posts: 49
Joined: 25 Nov 2006 07:43

Re: FM synthesis

Post by audiojunkie »

aldonecheeba wrote:hi all

i've been trying to figure out the FM controller, but no positive results


what bloc should by before it, of after ? can somebody post a patch to show that?

thanks
I'd be interested in knowing this too. I've never tried my hand at FM synthesis, because I always just thought it was too difficult (for me). :oops:

--Sean
aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

the best i could do

Post by aldonecheeba »

i took inspiration from the DX10 plugin of FL studio 7

(i copied the structure)
and this is the best i could come out with:

http://www.4shared.com/file/15183342/ae ... to_FM.html

but even by tweaking i could not get the same sound
karmafx
Site Admin
Posts: 1194
Joined: 07 Mar 2005 16:37

Post by karmafx »

This is actually an interesting topic...
I've never really tested and compared the FM in the synth to operator based FM (!)

Thanks for the patch aldonecheeba ! You have the right idea....

The simplest basic FM patch is simply: Osc -> FM -> Out

Set Osc to e.g. sine and tweak the modindex in the FM. Also try changing the Carier / Modulator relationship....

This is actually "real" Frequency modulation, since the FM controller changes the frequency control signal sent to the oscillator.
I say that, because when some people talk about FM they're really doing phase modulation.

When chaining several FM modules, only one of them should trigger (control the notepitch).
One of the problems with FM in a digital system is aliasing (hence the antia(lias) led button), but I might need to oversample the signal,
and make changes to the FM module to get the right sound you want ?!

If you have any ideas for improvements or maybe sound examples of the sound your'e after, just email me!

(btw: If at all possible, please use fxp when exporting future patches, to make it really easy for others to import.)
aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

the sound i'm looking for

Post by aldonecheeba »

really i don't know what i'm looking for.


actually your modular synth is for me the "kingdom of virtual circuit bending"
so your idea of oversampling is great, but not just for FM.

what i think would be great is an option in the options with "oversampling 2x, 4x, 8x" something like that, and the same thing for "simulation speed 2x 4x..."

and the CPU would be the limiting factor

and for the sounds of other plugins...i don't know you can't trust them, they just copy each other i think to get warmer or PROer...that doesn't lead anywhere.

anyway great job i spend entire days in front of your work
aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

FXP ?

Post by aldonecheeba »

there's this fxp export format i can't find anything about it in the forum,

FL studio doesn't export to that format it has FST for plugins patches, anyway
inside karma fx synth there's apparently nothing about it.
karmafx
Site Admin
Posts: 1194
Joined: 07 Mar 2005 16:37

Post by karmafx »

strange that FL cannot export fxp ....but if it can't you have to use the kfx ones I guess...you cannot do it from within the synth.
aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

i just saw it in the help...it can

Post by aldonecheeba »

it can do that using the wrapper plugin used to host external vst and dxi

ok then



and about the oversampling idea, i think i was wrong, it's better to have just some plugins with that feature (or it might really blow up the cpu)
karmafx
Site Admin
Posts: 1194
Joined: 07 Mar 2005 16:37

Post by karmafx »

Regarding FM, I think the current impl gives somewhat similar results to my old hw synth..but oversampling would help represent the generated sidebands with high freq modulation (without aliasing like hell)...

However, I would very much like it to be possible to build FM operator like setups in KarmaFX Synth too... but I havn't looked too much into that.

I'm currently considering what to do with oversampling. Havn't decided wether it should be a global or local (per module) option yet.

Feel free to comment if you have any ideas or suggestions...
aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

looking for some suggestions

Post by aldonecheeba »

ok
i had to open it to see what it needs, so here are some suggestions, not about the sound, just the workflow:

-to have an option about enabling or not to show windows content while moving them

-simplify the making of skins by putting them not in a dll, but in a folder with lots of BMPs, or in on BIG image ? (to be able to modify the graphics using just paintbrush)

and to have one transparent color wich would be known by the program as a little square in a corner of the image

-to be able to change animation update rate (and why not to sync it with the beat ?)

-and enable disable snapping

all this is really not necessary but could help to grow the community
aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

now one real suggestion

Post by aldonecheeba »

the sampler is nearly perfect

but i think it would benefit from cue start point and end point (but let the start and lenght knobs) like what you've done with the looping points.
aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

great FM synthesis achieved !!

Post by aldonecheeba »

man it was really simple,
there even was no need to make an FM module!

here is it : http://www.4shared.com/file/15235717/70 ... eatFM.html


but now i feel that anti aliasing more than necessary...you can't use a modulator at a frequency higher than 400Hz !
karmafx
Site Admin
Posts: 1194
Joined: 07 Mar 2005 16:37

Post by karmafx »

yeah...that works too! :shock: :-)

but the problem with this approach is that it is inharmonic (non integer carrier/modulator relationship)....

so to do other stuff than e.g. bells, you can use the HFO and rout it into the centered "freq" knob on the frequency controller. The HFO has an FM mode you need to enable.

Like you already discovered, it can alias... However, you might be able to use "porta" to lowpass the incoming freq changes to reduce aliasing somewhat.

I would really like to have a better anti aliasing approach...
aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

non programmer trying to help a programmer

Post by aldonecheeba »

i heard about the google code search a while ago...

it could help, perhaps there are algorithms or thing like that:

http://www.google.com/codesearch
karmafx
Site Admin
Posts: 1194
Joined: 07 Mar 2005 16:37

Re: looking for some suggestions

Post by karmafx »

aldonecheeba wrote: -to have an option about enabling or not to show windows content while moving them
not sure what you mean....please explain :-)
aldonecheeba wrote: -simplify the making of skins by putting them not in a dll, but in a folder with lots of BMPs, or in on BIG image ? (to be able to modify the graphics using just paintbrush)
man, can you read my mind or something? :wink: ....I'm already coding that separate folder thingy.
aldonecheeba wrote: and to have one transparent color wich would be known by the program as a little square in a corner of the image
Again, I'm confused...what do you need transparency for?
aldonecheeba wrote: -to be able to change animation update rate (and why not to sync it with the beat ?)
The host usually dictates the update rate...but the sync to beat idea is new! nice.
aldonecheeba wrote: -and enable disable snapping
why oh why ? but ok... :-)

btw: KarmaFX Synth has a resource script that describes the size and names of images as well as GUI colors, and even wire thickness and colors too.... So serious GUI hacking should be possible :D
aldonecheeba
Posts: 17
Joined: 02 May 2007 13:59
Location: toulouse france

explanashun

Post by aldonecheeba »

_for not seeing the windows content while moving it:
it's for the modules, when i move them it feels slow because of the frame update frequency, so i though it would be faster on the eye to have the module diseppear while you're moving it (like that you never see a moving module, it give an impression of stability, steadyness...)

_transparent color...no i don't need it, nobody does and it just wastes CPU cycles. i wrote that only because it came after the good idea of the pictures folder...(all ideas are not equal)

_the sync frame rate to beat would be for me a nice way to heavily limit the framerate and in the same way make the end user happier, he doesn't know that we're fooling him !! :)

_and for snapping, i think it affects freedom of movement, and i didn't see it use in any patch i saw. but another feature i'm just thinking about would be to have a grid, and to snap modules to the grid, that would feel Mastered and retro-technological

anyway you're the boss boss, whatever you do will just make it better!
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