FM The Grid vs. FM-4

[Trancit]

Well, seems like Bitwig representative says that Phase Modulation is equivalent to linear FM, so I guess that's why we don't have linear FM input. But they are different and it become more apparent with mixing different waves, like saw modulating sine and such. Guess we need to send emails to request addition of linear FM or at least checkbox in inspector panel to make pitch input behave like linear frequency input.

I always read "linear" or "exponential"... did really nobody realize two Math function in 'TheGrid called "Log" and "Power"? Using them you can transfer a linear input signal to an exponential output and vice versa (linear to logarithmic). So it's nonsense to claim that as a barrier.

I don´t think, that the linear or exponential is happening on "before" the carrier...
I happens inside of the Osc you want to modulate on the "way" from the input via the pitch mod knob to the sound generator respectively the scaling of the pitch mod knob and there is no way to influence this signal flow with the from you named modules... so the barrier still exists from my understanding...

[pdxindy]

And BTW... the problem isn't the modulation itself (it works, I tested it several times using phase in as well as pitch in - not only with sine wave oscillator...). My problem was and still is the inability to use the output of these oscillators to mix them back to their inputs (some kind of feedback, which is the problem according to Bitwig Support). This would be necessary if one wants to make a similar mix matrix like FM4 comes with. Missing this matrix the whole concept of inter-modulation is nearly useless.

Use the Phase-1 Osc which has a feedback parameter

[kurt008]

And BTW... the problem isn't the modulation itself (it works, I tested it several times using phase in as well as pitch in - not only with sine wave oscillator...). My problem was and still is the inability to use the output of these oscillators to mix them back to their inputs (some kind of feedback, which is the problem according to Bitwig Support). This would be necessary if one wants to make a similar mix matrix like FM4 comes with. Missing this matrix the whole concept of inter-modulation is nearly useless.

Use the Phase-1 Osc which has a feedback parameter

A solution like in FM4 isn't realizable because of coding issues (because of buffering of the signals, a.o.), so that FM4 will remain the only solution for such purposes. This information I got from the Bitwig support by mail a few weeks ago.

[pdxindy]

And BTW... the problem isn't the modulation itself (it works, I tested it several times using phase in as well as pitch in - not only with sine wave oscillator...). My problem was and still is the inability to use the output of these oscillators to mix them back to their inputs (some kind of feedback, which is the problem according to Bitwig Support). This would be necessary if one wants to make a similar mix matrix like FM4 comes with. Missing this matrix the whole concept of inter-modulation is nearly useless.

Use the Phase-1 Osc which has a feedback parameter

A solution like in FM4 isn't realizable because of coding issues (because of buffering of the signals, a.o.), so that FM4 will remain the only solution for such purposes. This information I got from the Bitwig support by mail a few weeks ago.

That is in reference to feedback between Grid modules. Feedback within a module can be done and they have since added the feedback option to the Phase-1 Osc.

[kurt008]

Well, seems like Bitwig representative says that Phase Modulation is equivalent to linear FM, so I guess that's why we don't have linear FM input. But they are different and it become more apparent with mixing different waves, like saw modulating sine and such. Guess we need to send emails to request addition of linear FM or at least checkbox in inspector panel to make pitch input behave like linear frequency input.

I always read "linear" or "exponential"... did really nobody realize two Math function in 'TheGrid called "Log" and "Power"? Using them you can transfer a linear input signal to an exponential output and vice versa (linear to logarithmic). So it's nonsense to claim that as a barrier.

I don´t think, that the linear or exponential is happening on "before" the carrier...
I happens inside of the Osc you want to modulate on the "way" from the input via the pitch mod knob to the sound generator respectively the scaling of the pitch mod knob and there is no way to influence this signal flow with the from you named modules... so the barrier still exists from my understanding...

You seemingly don't understand the signal properties as well as the signal scaling. Fact is, that pitch input signal understood by oscillators is processed by a power function in order to find the frequency to generate, in opposite to the linear signal coming from an oscillator out (or at least as it mostly is interpreted). Of cause there is a power function inside an oscillator, but the signal can be pre-processed with Log, so in the end there's a completely linear frequency response. I already tested this and it works. Of cause you need to adjust a few values, but... Math offer all necessary functions. As I told: The claim that the pitch-frequency exponential-linear problem is an issue is simply a pure nonsense and shows only one thing: The person talking this way isn't able to calculate - period (sorry guys, but this is a fact).

[kurt008]

And BTW... the problem isn't the modulation itself (it works, I tested it several times using phase in as well as pitch in - not only with sine wave oscillator...). My problem was and still is the inability to use the output of these oscillators to mix them back to their inputs (some kind of feedback, which is the problem according to Bitwig Support). This would be necessary if one wants to make a similar mix matrix like FM4 comes with. Missing this matrix the whole concept of inter-modulation is nearly useless.

Use the Phase-1 Osc which has a feedback parameter

A solution like in FM4 isn't realizable because of coding issues (because of buffering of the signals, a.o.), so that FM4 will remain the only solution for such purposes. This information I got from the Bitwig support by mail a few weeks ago.

That is in reference to feedback between Grid modules. Feedback within a module can be done and they have since added the feedback option to the Phase-1 Osc.

I know. Some time before I mailed an issue of Beta (I guess it was Beta 3 / 3.0, but I'm not sure) and asked for that feature. I also told them, that LongDelay was used at that time by some users for such purposes. You know since that time LongDelay don't work any longer as 'feedback-enabler'. My question though targeted a general solution for realizing such mixing matrices inside TheGrid, which would help realizing very interesting combination (because as you know the matrix inside FM4 can't be modulated, but it would be capable to be modulated inside TheGrid)

[pdxindy]

You know since that time LongDelay don't work any longer as 'feedback-enabler'.

Still works here on beta 6... (same 1 buffer delay of course)

[mclstr]

P.S. The skew control on the sine VCO is basically the same as self PM(FM) modulation. So no need to jump through hoops to feed it back into itself to do it. And since you can modulate the skew control you have all the options.

[Trancit]

You seemingly don't understand the signal properties as well as the signal scaling. Fact is, that pitch input signal understood by oscillators is processed by a power function in order to find the frequency to generate, in opposite to the linear signal coming from an oscillator out (or at least as it mostly is interpreted). Of cause there is a power function inside an oscillator, but the signal can be pre-processed with Log, so in the end there's a completely linear frequency response. I already tested this and it works. Of cause you need to adjust a few values, but... Math offer all necessary functions. As I told: The claim that the pitch-frequency exponential-linear problem is an issue is simply a pure nonsense and shows only one thing: The person talking this way isn't able to calculate - period (sorry guys, but this is a fact).

Not only that I cannot calculate, I do not even understand anything you wrote... but:

I know how to spell "of course"

Anyway... I would like to see a grid preset, which is useable and sounds like a normal FM synth...
Just 2 osc sines A modulating B...

[mclstr]

Anyway... I would like to see a grid preset, which is useable and sounds like a normal FM synth...
Just 2 osc sines A modulating B...

Are you kidding, or haven't you tried yet?
Works just like any other PM (FM) synth for me and there are many presets out there demonstrating it as well.

Of course it can be a mess when you start running separate envelopes, LFOs, mixers for a a seven operator DX7 style, but it can be done.

[x.iso]

I always read "linear" or "exponential"... did really nobody realize two Math function in 'TheGrid called "Log" and "Power"? Using them you can transfer a linear input signal to an exponential output and vice versa (linear to logarithmic). So it's nonsense to claim that as a barrier.

Sure I've tried, but it doesn't work as straightforward, because the problem is within oscillator, how it applies the modulation. No matter what you do it applies modulation to pitch range, and it's hard to correct for that and get proper linear function.

And BTW... the problem isn't the modulation itself (it works, I tested it several times using phase in as well as pitch in - not only with sine wave oscillator...). My problem was and still is the inability to use the output of these oscillators to mix them back to their inputs (some kind of feedback, which is the problem according to Bitwig Support). This would be necessary if one wants to make a similar mix matrix like FM4 comes with. Missing this matrix the whole concept of inter-modulation is nearly useless.

they added self-feedback for Phase-1, I guess in time they could do it for the rest of the OSC's.

[pdxindy]

they added self-feedback for Phase-1, I guess in time they could do it for the rest of the OSC's.

IMO, no reason to do so. All the Osc's have already interesting and musical self modulations

[Trancit]

Anyway... I would like to see a grid preset, which is useable and sounds like a normal FM synth...
Just 2 osc sines A modulating B...

Are you kidding, or haven't you tried yet?
Works just like any other PM (FM) synth for me and there are many presets out there demonstrating it as well.

Of course it can be a mess when you start running separate envelopes, LFOs, mixers for a a seven operator DX7 style, but it can be done.

Yes you´re right...
Even if I have to say, it just works really with PM if you put a level module after the modulator and crank up the level to about +15db...
This is what I´ve missed the last time... if you leave the original volume of the modulator, the PM modulation goes only up to about 60% of FM modulation in normal FM Synths or in Synths with FM capabilities like i.e. Serum ... that´s why I didn´t try any further... PM does the trick but only with higher Modulator volume...

But with that tweak, the problem is solved for me...
Thx for all your input...

[Yokai]

Well, seems like Bitwig representative says that Phase Modulation is equivalent to linear FM, so I guess that's why we don't have linear FM input. But they are different and it become more apparent with mixing different waves, like saw modulating sine and such. Guess we need to send emails to request addition of linear FM or at least checkbox in inspector panel to make pitch input behave like linear frequency input.

I always read "linear" or "exponential"... did really nobody realize two Math function in 'TheGrid called "Log" and "Power"? Using them you can transfer a linear input signal to an exponential output and vice versa (linear to logarithmic). So it's nonsense to claim that as a barrier.

And BTW... the problem isn't the modulation itself (it works, I tested it several times using phase in as well as pitch in - not only with sine wave oscillator...). My problem was and still is the inability to use the output of these oscillators to mix them back to their inputs (some kind of feedback, which is the problem according to Bitwig Support). This would be necessary if one wants to make a similar mix matrix like FM4 comes with. Missing this matrix the whole concept of inter-modulation is nearly useless.

The Phase-1 osc module has an internal feedback knob right there in the lower right side of the module. This is to enable you to build a pseudo Phase-4 Instrument in the Grid, where they all can mod each other and also feed back into themselves.

Will they eventually add a similar type of internal feedback knob into the other osc modules? Who knows? (shrug)

[Tj Shredder]

To demonstrate how the DX7 architecture could be reproduced in the grid, I made a project with all 32 algorithms in a rough version. For algos 2-6 and 16 I tried a quick and dirty recreation of some classic DX7 sounds. It works quite well. If you ever programmed a DX7 you will quickly come to useful results but have much more options with the oscillators and all the other Grid stuff...