Amplitude modulation using an oscillator as a modulator?

[EarHax]

Is it possible to somehow use operator or some other signal generator in Live to do amplitude modulation of another source? I'm tearing my hair out trying to figure out how to do high frequency AM synthesis in here. Please let me know if there's a way. Thanks!

[tedlogan]

If you have Max 4 Live, you can use LFO, or even better in this case, LFO 2.0.5 http://www.roberthenke.com/technology/lfo.html

If you don't have it, pester Ableton to make these devices native, as we all do.

[Idonotlikebroccoli]

Thanks! I didn't know about LFO 2.0. Max for Live is kind of unstable though, so I also wish there was a native device.

[EarHax]

It appears the M4L Tremellow effect can do pretty decent amplitude modulation. There is a preset for it called Amplitudinar Modulation that words pretty well.

[stringtapper]

Yeah, the only native solution I know of is to use the Auto Pan device set to 100% and a phase of 0.00º, but you're still limited to 90Hz.

With M4L rolling your own AM device is dead simple.

[EarHax]

If you have Max 4 Live, you can use LFO, or even better in this case, LFO 2.0.5 http://www.roberthenke.com/technology/lfo.html

If you don't have it, pester Ableton to make these devices native, as we all do.

I tried the LFO 2.0, mapping it to the track volume. But it seems like when I modulate at higher frequencies, it introduces unwanted noise as opposed to just the amplitude modulation, and doesn't work quite as well as expected.

Basically, if you have ever used a modular analog synth to do high frequency amplitude modulation, you know the formant frequencies you can produce with it (vowel sounds). I just haven't been able to figure out how to do this very well in Live using AM.

[stringtapper]

Basically, if you have ever used a modular analog synth to do high frequency amplitude modulation, you know the formant frequencies you can produce with it (vowel sounds).

I've only done it with Max, but I know exactly what you mean.

I tried the LFO 2.0, mapping it to the track volume. But it seems like when I modulate at higher frequencies, it introduces unwanted noise as opposed to just the amplitude modulation, and doesn't work quite as well as expected.

That's likely happening because M4L is controlling the track volume (and the track volume in general can probably only move) at control rate rather than signal rate.

You need an audio effect that's actually modulating the audio directly. That Tremellow device should work, but I'm not in front of it right now to know what the frequency range is on it.

[EarHax]

You need an audio effect that's actually modulating the audio directly. That Tremellow device should work, but I'm not in front of it right now to know what the frequency range is on it.

Whatever the range is, I bet I could edit the M4L device and tweak it to get it to the range I want.

Oh man how I love M4L!

[Steve Glen]

You can use the sidechain feature in either Compressor or Gate. These are built right into Live.

Place these devices on the track you are trying to modulate, then engage SC and select the oscillator as your source.

[EarHax]

You can use the sidechain feature in either Compressor or Gate. These are built right into Live.

Place these devices on the track you are trying to modulate, then engage SC and select the oscillator as your source.

Please elaborate. I don't see how using an operator via sidechain will create amplitude modulation on another track. It seems to me it will just do typical sidechain compression. Maybe I'm not picturing the setup right from the way you described it. Maybe a step by step?

[Steve Glen]

oh whoops. You don't want to modulate the amplitude, you want amplitude modulation. Right, ok.

[EarHax]

oh whoops. You don't want to modulate the amplitude, you want amplitude modulation. Right, ok.

Yeah. Sort of how frequency modulation is the same as pitch shifting.

[Michael Hatsis]

What about the ring mod in the frequency shifter device? Ring mod is pretty much AM

[EarHax]

What about the ring mod in the frequency shifter device? Ring mod is pretty much AM

Pretty much, but not really. The difference between amplitude modulation and ring modulation is that in AM the carrier frequency is preserved and the sidebands generated are at half the amplitude of the carrier amplitude. In RM you lose the carrier, and you just get the difference and sum of the carrier and modulator.

So ring modulating your bass is going to throw it out of tune with the rest of the music, whereas using AM the carrier remains and you get added sidebands.

[WhiteNoise0]

What about the ring mod in the frequency shifter device? Ring mod is pretty much AM

Pretty much, but not really. The difference between amplitude modulation and ring modulation is that in AM the carrier frequency is preserved and the sidebands generated are at half the amplitude of the carrier amplitude. In RM you lose the carrier, and you just get the difference and sum of the carrier and modulator.

So ring modulating your bass is going to throw it out of tune with the rest of the music, whereas using AM the carrier remains and you get added sidebands.

RM with dry/wet at 50% and you have an AM. Simple math.