Using Global Modulators in Bitwig for Interchannel Communication
Tutorial | Jun 09, 2023
In this video, I explore using global modulators in Bitwig to send signals from one channel to another. I start by showing how it's not easy to route signals from the Polygrid device to a different channel. Then, I suggest using a DC offset in the FX box and muting the channel to generate audio signals that can be grabbed with an audio rate modulator to easily modulate something on a different channel. I explain how this workaround can be used on multiple channels and how it can be set up as a preset for future use. I also note that there could potentially be latency issues when using multiple VSTs, but I haven't tested it yet.
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The video is a tutorial on how to use global modulators in Bitwig for interchannel communication in Bitwig. Interchannel communication is a process of sending signals from one channel to another channel to modulate something. It can be used for modulating various parameters in different channels using methods such as audio rate modulation tools or sending MIDI data around and using the MIDI CC device1.
The video highlights the challenges in routing signals between channels due to the absence of software or features within Bitwig to facilitate interchannel communication. The tutorial then presents a workaround using a DC offset in the FX box. The DC offset device is an effect that generates a constant voltage or offset. It is used to generate audio signals by sending a modulator signal to the DC offset device, which generates an audio signal that can be used for modulation. The signal generated by the DC offset device can be muted if needed, and multiple instances can be used on different channels to generate different signals1.
This workaround, involving the use of global modulators, can be used on multiple channels and can be set up as a preset for future use. However, the video also notes some potential drawbacks. For instance, there could potentially be latency issues when using multiple VSTs, and this method may be considered a "hack" as it uses a workaround instead of a direct feature. Nevertheless, it is useful for the current Bitwig software and provides a way to modulate parameters between channels until more specific features for interchannel communication are developed in the future
Questions & Answers #
Maybe you dont watch the video, here are some important takeaways:
Questions #
What is interchannel communication and how is it used for modulation? #
Interchannel communication is a process of sending signals from one channel to another channel to modulate something. It can be used for modulating various parameters in different channels using methods such as audio rate modulation tools or sending MIDI data around and using the MIDI CC device.
What are the limitations of interchannel communication and how does the global modulator help in this? #
The limitations of interchannel communication include the lack of easy routing of signals between channels and the absence of software or features within Bitwig to facilitate interchannel communication. However, the global modulator can help in this by allowing for the generation of audio signals that can be used to modulate different parameters in different channels. This workaround can be used until more direct and specific features for interchannel communication are developed in the future.
What is the DC offset device and how is it used to generate audio signals? #
The DC offset device is an effect used in the FX box that generates a constant voltage or offset. It is used to generate audio signals by sending a modulator signal to the DC offset device, which generates an audio signal that can be used for modulation. The signal generated by the DC offset device can be muted if needed, and multiple instances can be used on different channels to generate different signals.
What are some potential drawbacks of using the global modulator method for interchannel communication? #
One potential drawback of using the global modulator method for interchannel communication is the possibility of latency issues if a lot of VSTs are used on the channel. It is important to test for latency issues when using this method. Another drawback is that this method may be considered a hack as it uses a workaround instead of a direct feature. However, it is useful for current Bitwig software and provides a way to modulate parameters between channels until more specific features are developed in the future.
Transcription #
This is what im talking about in this video. The text is transcribed by AI, so it might not be perfect. If you find any mistakes, please let me know.
You can also click on the timestamps to jump to the right part of the video, which should be helpful.
[00:00.000] Hey folks welcome back to another video. I made recently or not recently a year ago
[00:06.200] I made a video about interchannel communication where you can send signals from one channel
[00:11.600] to the other channel to modulate something. And nothing really has changed since then.
[00:19.160] We are still stuck with the audio rate modulation tools or with sending MIDI data around and
[00:26.640] using the MIDI CC device. I linked to this video in the description so you can rewatch
[00:33.200] it if you want to. And this video I want to talk about how you can maybe use the global
[00:39.920] modulate us for that. So let's imagine you have your one channel with an instrument on it,
[00:45.680] right? It's just a polymers synthesizer you're playing some kind of melody. And on a different
[00:53.960] channel you have maybe a polygrid. And in here you may be built some kind of generative device
[01:03.320] and the generative stuff here I'm just using a steps modulator. And you modulate with this
[01:11.400] thing here inside of the polygrid you can modulate all kinds of things, right? You maybe have a
[01:15.880] sign oscillator in here and then you take this, right? And so you modulate something in within
[01:23.400] the grid. But now you want to modulate something on the different channel on the polymer here.
[01:29.720] And you want to change something in modulation values, right? So that's not that easy because
[01:35.320] you can't get any signal here out of the polygrid that easy. I mean we have certain
[01:42.280] out modules here. We have the audio out. It just gives you audio out of the back here of the
[01:48.520] polygrid. So there's no things here you can use to route something to a different channel.
[01:54.760] There's hardware out here. You can only select your basically hardware outputs of your
[02:01.480] sound card. Nothing within Bitwig, right? You can't use anything to a different channel with this.
[02:09.800] Also CV out for instance here only uses as a destination hardware outputs. So there's nothing really
[02:19.560] you can use that's your CC out there you get CC data out of the back of the polygrid here. So
[02:28.360] there's nothing really there you can use to get different signals out of the grid easily.
[02:35.240] So my approach would be to go in the FX box and use a DC offset with this DC offset into an FX layer
[02:47.320] here and maybe call this let's say out one and then you can mute this channel. Let's call it out one.
[02:58.200] Mute this channel and then duplicate this maybe say this is out two and this is
[03:05.560] out three. You can do as many as you want, right? And because we muted this we can now modulate
[03:13.160] basically. Let's use a modulator out here. You can modulate your out one.
[03:20.680] You can see we get now here the data from the steps mod in the DC offset.
[03:31.080] And with this with this data we can now play around. We can for instance use this here and go
[03:39.640] to the polymer and say audio rate and then we can grab this here from the first channel.
[03:46.680] Polygrid right. Polygrid change out FX. FX change then we see here out one pre.
[03:54.280] Outpost is muted because we muted the whole channel so we get the post data but we get a pre
[04:00.680] here and it's all we need and you get here the step signal right
[04:07.560] from the polygrid one channel above and then you can use this and maybe modulate here the cutoff.
[04:16.600] So so far so good and yeah you can do this on multiple channels so when you create your another
[04:26.680] channel and use a pull-in pull-in synth on there you can basically do the same maybe copy and paste
[04:33.560] this here and you get the data here right then you can modulate your also the cutoff if you want to
[04:40.440] so this is basically what I explained in the in the recent on the last video about this about
[04:46.680] this topic but now with the global modulators we can basically do the same thing here
[04:59.800] here right so we can paste basically the audio rate in here and then call this out one
[05:07.560] and then you can do the same thing here and maybe grab a different one let's say a polygrid
[05:18.280] FX out two pre right so now we can use different modulator and in there maybe a random mod
[05:29.160] something like this and with this one we modulate of course here out two
[05:38.200] so here we have now different data right and this one is called out two
[05:46.440] so on the first channel now we generate data inside the polygrid we maybe have here some kind of
[05:51.320] patch running some generator of patch and then we feed out certain signals to the FX box here
[05:59.480] into an FX layer onto different layers on these layers there is a DC offset device you modulate
[06:05.960] this DC offset device and generate audio signals these audio signals are muted because we mute
[06:12.120] the channel here and then we grab these audio signals with an audio rate modulator on the project
[06:18.360] panel here with this device selector so we grab this data and then we can use this globally in our
[06:28.600] in our project we can go down here basically to our policing so instead of attaching here these
[06:34.280] modulators to each of these devices we can just grab here the audio data from the project panel
[06:40.600] and modulate something and because it's audio data it's audio rate so you have no real
[06:50.120] yeah I think inside the grid here when you use these modulators there are some kind of
[06:56.200] smoothing happening but I think in most cases when you want to modulate something it doesn't actually
[07:07.000] yeah matter that much so you can use this freely here as you want and you can use as many
[07:13.320] audio rate modulators as you want you can use as many outputs here with DC offset devices in
[07:19.000] this FX layer as you want so there's no real drawback so this is kind of a hack I would say it's not
[07:25.560] intended to use it that way but you can so maybe in the future we get some special grid outputs
[07:34.360] for signals for nodes or maybe for audio outputs maybe you also want to output different
[07:41.000] multi-channel audio outputs from the grid so there's also something people want all the time
[07:48.040] so maybe we get something in the future so we don't need to use here this DC offset device hack
[07:55.560] which works for now but you know it's kind of an hack it's not direct it's not intended that way but
[08:02.760] it kind of works so I want to show you this that you can use the grid or that you can use the
[08:08.760] audio rate modulators and the project panel for this maybe it's it's a better workflow because
[08:14.520] you can set this up here as a preset you can set this up as a preset maybe call this here
[08:19.880] signal out and then save it as a preset right and every time you need something like this
[08:29.160] recall it signal out and then maybe call it utility and you're done okay so that's for now that's
[08:41.720] what I want to show you I haven't made any tests with the latency of maybe there are some latency
[08:48.520] issues still with the global modulators here if you put a lot of VSTs on there and you introduce a
[08:53.480] lot of latency maybe some of these signals are too late you have to test this I haven't tested
[09:01.320] our jet but I want to give you here a rough idea how this works so yeah that's it for this video
[09:08.760] thanks for watching leave a like if you like the video if you found it helpful and yeah ask some
[09:14.600] questions in the comments of course see you in the next video thanks for watching and bye