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I was under the impression that, despite the name, the Yamaha FM synths didn't actually use frequency Modulation but rather phase modulation. With Frequency mod

I was under the impression that, despite the name, the Yamaha FM synths didn't actually use frequency Modulation but rather phase modulation. With Frequency modulation you can't have an operator feed back on its self. If you take a DX7 patch and implement it on something like the PreenFM2 or PreenFM3 (which uses actual FM), any algorithm with more than a few operators is going to sound quite different. I still love the old Yamaha FM synths though, the lo-fi-ness of the DACs are so musical/magical. Here's a IDM track I made with just the Yamaha TX81z 4op FM synth. https://soundcloud.com/cassilda_and_carcosa/ontologies-tape-tx81z-bass-mix?in=cassilda_and_carcosa/sets/marantz_cp_430 https://soundcloud.com/cassilda_and_carcosa/ontologies-tape-...

deleted 5y ago
[deleted]
jacquesm 5y ago
Wow, that transported me right back to my first experience listening to Kraftwerk. Thank you, keep it up, very well done!
- xattt 5y ago
  I’m getting Aphex Twin out of this!
  - weatherlight 5y ago
    7\ Thanks!
klodolph 5y ago
> I was under the impression that, despite the name, the Yamaha FM synths didn't actually use frequency Modulation but rather phase modulation. With Frequency modulation you can't have an operator feed back on its self. It’s true that it’s phase modulation, but phase is just the derivative of frequency, and the derivative is a linear operator (essentially a 6dB/oct EQ). So I don’t think it’s an especially important piece of terminology to get correct. The statement about feedback is actually backwards. You cannot directly incorporate feedback into a phase modulation system. In the Yamaha system, the feedback is delayed by a sample to make it work. In an FM synth, this would not be necessary, and you could just directly feed the output back into the input.
- weatherlight 5y ago
  One thing that is different in the preenfm2 compared to the Yamahas stuff is, that it uses linear FM and therefore will not do operator feedback. The guy behind the preenfm2 says, that feedback is not that important, when you have a variety of waveforms for modulation. Linear FM also has the advantage of being a bit "friendlier/warmer" when using complex waveforms as modulators (Higher harmonics of the modulator will have a smaller effect than in phase modulation). One thing you loose when not having feedback: The normal feedback happens after the amplification/envelope if I remember correctly Therefore the amount of feedback scales with the amplitude. With feedback you therefore get less harmonics and therefore a "softer" sound at lower amplitudes. This is quite useful, because it mirrors the behavior of most natural sound sources. It is the same idea as using a lowpass gate or using the same envelope for the amp and the filter in subtractive synthesis. Of course FM synths give you enough options to get this effect in another way. I still like the yamaha style feedback though....
  - klodolph 5y ago
    I will say—my personal experience, in dissecting DX7 presets, is that feedback is not really used that much. If you are porting DX7 sounds to a different architecture, you can remove the feedback and replace it with something like a noise source, or another operator, much of the time, or even remove it altogether. This is just my personal experience. I often dig through DX7 patches in order to reimplement them for demoscene projects. Sounds like you’re getting good use out of the TX81Z. I have the TX802, which is on paper a better synth, but controlling it from a DAW is much more of a pain because the program change messages control the “performance”, rather than the patch. So it’s been exiled from my rack, at least for now.
    - weatherlight 5y ago
      if you try to control the parameters on the TX81z while its receiving midi info, it starts to "skip" and the notes start to lag, lol. I wish i had a TX802 or a fs1r yamaha. Those are so nice!
    - ajxs 5y ago
tekstar 5y ago
Woah! Are the drums also TX81Z? That sounds great!
- weatherlight 5y ago
  TX81z sampled and trigger with an elektron rytm mk2. also, thanks!
weatherlight 5y ago
also on spotify -> https://open.spotify.com/track/0m3XklXAjsJAnSMgl2Upif?si=391ffc5706b54241 https://open.spotify.com/track/0m3XklXAjsJAnSMgl2Upif?si=391...
jdontillman 5y ago
"FM Synthesis" is a generic term that encompasses both phase modulation and frequency modulation. And in John Chowning's original article, he bops back and forth between the two without mentioning it. In practice, phase modulation is more useful and makes more sense. And yes, the DX-7 uses phase modulation throughout. --- With Frequency Modulation, you can have an operator feed back on itself. However... with such an arrangement it is entirely possible for it to get stuck at 0 Hz. Not very musical. --- And phase modulation makes a lot more sense. Watch as I demonstrate. Student: "How does FM synthesis work?" Teacher: "Well, do you know what happens if we have one oscillator modulating the frequency of another oscillator?" Student: "You mean like vibrato?" Teacher: "Yes, exactly. Now imagine a vibrato at the same frequency as the second oscillator." Student: "That's doesn't even make sense." Teacher: "Not to worry, the Bessel Functions still apply." Student: "What's a Bessel Function. Can I calculate it?" Teacher: "Not directly. It's kind of complicated." Student: "Mutherfucker!" Okay, now let's try phase modulation. Student: "How does phase modulation work?" Teacher: "Okay... Do you know how distortion works?" Student: "I'm a guitar player. I'm intimately familiar with distortion." Teacher: "Great! So distortion is a nonlinearity on the Y axis of a waveform." Student: "Yep!" Teacher: "Well, phase modulation is a nonlinearity on the X axis of a waveform. We stretch the waveform here [hand gesture], and compress the waveform over here [hand gesture]." Student: "Hmm, warping the waveform along the X axis. That sounds kind of like PWM." Teacher: "It's kind of similar, yeah." Student: "Cool; thanks. I understand."

deleted 5y ago

[deleted]

jacquesm 5y ago

Wow, that transported me right back to my first experience listening to Kraftwerk. Thank you, keep it up, very well done!

xattt 5y ago
I’m getting Aphex Twin out of this!
- weatherlight 5y ago
  7\ Thanks!

klodolph 5y ago

> I was under the impression that, despite the name, the Yamaha FM synths didn't actually use frequency Modulation but rather phase modulation. With Frequency modulation you can't have an operator feed back on its self. It’s true that it’s phase modulation, but phase is just the derivative of frequency, and the derivative is a linear operator (essentially a 6dB/oct EQ). So I don’t think it’s an especially important piece of terminology to get correct. The statement about feedback is actually backwards. You cannot directly incorporate feedback into a phase modulation system. In the Yamaha system, the feedback is delayed by a sample to make it work. In an FM synth, this would not be necessary, and you could just directly feed the output back into the input.

weatherlight 5y ago
One thing that is different in the preenfm2 compared to the Yamahas stuff is, that it uses linear FM and therefore will not do operator feedback. The guy behind the preenfm2 says, that feedback is not that important, when you have a variety of waveforms for modulation. Linear FM also has the advantage of being a bit "friendlier/warmer" when using complex waveforms as modulators (Higher harmonics of the modulator will have a smaller effect than in phase modulation). One thing you loose when not having feedback: The normal feedback happens after the amplification/envelope if I remember correctly Therefore the amount of feedback scales with the amplitude. With feedback you therefore get less harmonics and therefore a "softer" sound at lower amplitudes. This is quite useful, because it mirrors the behavior of most natural sound sources. It is the same idea as using a lowpass gate or using the same envelope for the amp and the filter in subtractive synthesis. Of course FM synths give you enough options to get this effect in another way. I still like the yamaha style feedback though....
- klodolph 5y ago
  I will say—my personal experience, in dissecting DX7 presets, is that feedback is not really used that much. If you are porting DX7 sounds to a different architecture, you can remove the feedback and replace it with something like a noise source, or another operator, much of the time, or even remove it altogether. This is just my personal experience. I often dig through DX7 patches in order to reimplement them for demoscene projects. Sounds like you’re getting good use out of the TX81Z. I have the TX802, which is on paper a better synth, but controlling it from a DAW is much more of a pain because the program change messages control the “performance”, rather than the patch. So it’s been exiled from my rack, at least for now.
  - weatherlight 5y ago
    if you try to control the parameters on the TX81z while its receiving midi info, it starts to "skip" and the notes start to lag, lol. I wish i had a TX802 or a fs1r yamaha. Those are so nice!
  - ajxs 5y ago

tekstar 5y ago

Woah! Are the drums also TX81Z? That sounds great!

weatherlight 5y ago
TX81z sampled and trigger with an elektron rytm mk2. also, thanks!

weatherlight 5y ago

also on spotify -> https://open.spotify.com/track/0m3XklXAjsJAnSMgl2Upif?si=391ffc5706b54241 https://open.spotify.com/track/0m3XklXAjsJAnSMgl2Upif?si=391...

jdontillman 5y ago

"FM Synthesis" is a generic term that encompasses both phase modulation and frequency modulation. And in John Chowning's original article, he bops back and forth between the two without mentioning it. In practice, phase modulation is more useful and makes more sense. And yes, the DX-7 uses phase modulation throughout. --- With Frequency Modulation, you can have an operator feed back on itself. However... with such an arrangement it is entirely possible for it to get stuck at 0 Hz. Not very musical. --- And phase modulation makes a lot more sense. Watch as I demonstrate. Student: "How does FM synthesis work?" Teacher: "Well, do you know what happens if we have one oscillator modulating the frequency of another oscillator?" Student: "You mean like vibrato?" Teacher: "Yes, exactly. Now imagine a vibrato at the same frequency as the second oscillator." Student: "That's doesn't even make sense." Teacher: "Not to worry, the Bessel Functions still apply." Student: "What's a Bessel Function. Can I calculate it?" Teacher: "Not directly. It's kind of complicated." Student: "Mutherfucker!" Okay, now let's try phase modulation. Student: "How does phase modulation work?" Teacher: "Okay... Do you know how distortion works?" Student: "I'm a guitar player. I'm intimately familiar with distortion." Teacher: "Great! So distortion is a nonlinearity on the Y axis of a waveform." Student: "Yep!" Teacher: "Well, phase modulation is a nonlinearity on the X axis of a waveform. We stretch the waveform here [hand gesture], and compress the waveform over here [hand gesture]." Student: "Hmm, warping the waveform along the X axis. That sounds kind of like PWM." Teacher: "It's kind of similar, yeah." Student: "Cool; thanks. I understand."