Renoise Native Monophonic Synthesiser

Using a few clever tricks it’s actually possible to do some basic synthesis in Renoise using nothing but native DSP devices.

I know this has been discussed before by other people on the forum, and there have been a few examples of creating ambient noises and sound fx this way, but I can’t remember if I’ve seen an actual playable instrument yet?

Anyway…

DC Offset provides the basic starter signal which is then modulated by the RingMod device, thus creating an oscillator. Then we can take a Key-Tracking Device and use it to reset an LFO with a carefully programmed custom envelope, which feeds into the RingMod frequency in order to tune it to the pitch of the notes you play. You now have the foundation of a monophonic synth! smile.gif/>

Some demos…

Breakdown of a basic sawtooth sound:
7632 dblue-ringmod-monophonic-synth-demo.xrns

Awesome job dblue! I’ve posted a similar idea in the past a couple of times, but your use of the line in device and custom LFO is vastly superior to my half-assed out-of-tune design.

Thanks for sharing!

It also works nicely with a looped sample of ‘nothing’ with DC offset applied to it, and in some cases this actually gives you more control over certain things. I just thought I would use the line-in device in this example to gain a few extra l33t points :)

Edit: I forgot to mention that I’m still ironing out a few potential problems with this setup, like making sure the DC offset doesn’t get too out of hand and cause a lot of distortion. This could be done with either a highpass filter or DC offset remover positioned directly after the RingMod device. I’m still experimenting to see which is best.

seriously, i have a lot to learn. everytime i read about stuff you do, i only understand half of what you are talking about. i have no idea what DC offset does, for example. impressive stuff, keep it up!

l33t points for you! :)

Nice, I’ll have to take a closer look at how to use the key tracking and velocity device more, I don’t use it as much as the other modulation devices.

Thanks :)

I do like this. Saved ‘looped silence’ version of the chain in my DSP presets folder.

Trickery like this makes the perfect demonstration use-case for allowing DSP chains inside instruments.

tried it yesterday, sounds coo!

Ufff … :blink:

dblue is a chance you can make some routing-pictures to make it clear how this work?
It is not easy to follow it. ^_^

Maybe this will be a bit easier to follow:
dblue-ringmod-monophonic-synth-demo.xrns

I’ve broken it down into 3 steps that show how I build things up:

  • 1: Basic oscillator sound
  • 2: Oscillator with a volume envelope
  • 3: Oscillator with volume and filter envelopes

Basically, the RingMod effect modulates the amplitude of a signal, right? If you put a vocal sample through RingMod, then you get that weird kind of robotic sound, because the voice is being modulated by a sinewave or whatever you’re using. Well, we can take advantage of this to actually produce new sounds, rather than simply modifying existing ones in the traditional way.

If you apply RingMod to silence, then you get… silence… because there’s no signal to actually modulate. So this is where the DC offset comes into play. By applying a manual DC offset to our silence, we now have a very rough (and very flat) signal that we can work with. We have changed the input audio from a constant stream of 0.0’s into a constant stream of 0.5’s, for example. When we apply RingMod to this new signal, it actually has some values that it can modulate, which in turn creates sound. We’re now changing that boring sound of ‘nothing’ into a sinewave, or a sawtooth, or a square, etc.

(I’ve included another instrument/sample called ‘Silence + DC Offset’ which simply shows the modified signal, to get a better understanding of how the DSP chain starts out)

From there, you can do more interesting things like shape the signal with a volume envelope. To do this I’m using a Gainer, which is being controlled by an LFO Device with a custom envelope shape, which is in turn being reset by a Velocity Device each time a note is triggered. You can do a similar thing with a Filter instead of a Gainer to give the sound a more interesting tone. The DSP chains might look complex, but it’s really just a combination of various simple things stacked together in order to change the sound. You don’t have to focus so much on these, just focus on the very basics first, and the rest will eventually fall into place.

The RingMod wouldn’t be very useful to begin with unless it could be accurately tuned to the correct frequency for each note, so this is where my first custom LFO comes into play. This was probably the trickiest part of the whole process. I had to write a program to generate the correct envelope points for all 120 notes (C-0 to B-9), which I copied as XML from my program into Renoise. I use the Key-Tracking device to read the note that is played in the pattern, and then I translate this to an LFO reset command that corresponds to the correct point in the custom envelope. The LFO then sets the RingMod frequency to the correct value to match the note.

Amazing stuff!!

To me, this is the best part: as each tone has a unique frequency, by changing the envelope’s points you can create a whole new scale, or just mess with the timbres.

Just to confirm, I made a pentatonic scale by removing a lot of the entries:

Click to view contents <?xml version="1.0" encoding="UTF-8"?>





1,0.28436067700386047

3,0.29536175727844238

6,0.3119971752166748

8,0.32315987348556519

10,0.33437255024909973

13,0.35128387808799744

15,0.362608402967453

18,0.37966114282608032

20,0.39106979966163635

22,0.40250486135482788

25,0.41970491409301758

27,0.43119710683822632

30,0.44846996665000916

32,0.46000456809997559

34,0.4715539813041687

37,0.4889005720615387

39,0.50047856569290161

42,0.51786315441131592

44,0.52946287393569946

46,0.54106992483139038

49,0.55849188566207886

51,0.57011312246322632

54,0.58755379915237427

56,0.59918630123138428

58,0.61082214117050171

61,0.62828171253204346

63,0.63992488384246826

66,0.65739405155181885

68,0.66904264688491821

70,0.68069314956665039

73,0.69817173480987549

75,0.70982581377029419

78,0.72730910778045654

80,0.73896592855453491

82,0.75062364339828491

85,0.7681117057800293

87,0.77977126836776733

90,0.79726171493530273

92,0.80892264842987061

94,0.82058405876159668

97,0.83807682991027832

99,0.84973913431167603

102,0.86723315715789795

104,0.87889611721038818

106,0.89055931568145752

109,0.90805447101593018

111,0.91971814632415771

114,0.9372139573097229

116,0.94887793064117432

118,0.96054208278656006

121,0.97803843021392822

123,0.98970276117324829



256

Pentatonic is also known as the “black keys scale”. In this scale, there’s only 52 frequencies for entire keyboard, or 5 per octave.
Paste the code into the LFO device’s custom envelope, et voila. It can even be saved as a new LFO device preset…

awesoemz!

Exactly :)

The program I wrote to help me generate the envelope points actually takes this into account. I set it up so that it would be possible to put in your own custom tunings, for example. I’ll try to clean it up at some point and release it as a public tool.

Sorry mate, did you already post this technique somewhere?

Taking this concept a few (big) steps further…

Here’s a quick little electro(ish) demo pattern that I’ve created:
dblue-renoise-native-device-synth-demo.xrns

It even has drums!

To be perfectly honest, I’ve even surprised myself by what is actually possible here. It’s been great fun experimenting with this! Hopefully it will inspire some of you to dig a little deeper into the awesome power of Renoise :)

Edit: Something a bit more dubstep-y just for fun:
dblue-renoise-native-device-synth-demo-v2.xrns

Nailed the concept truly and completely ^_^

I like the use of lo-fi as a noise generator. And there I was feeding detuned sine-waves into a 100% fold distortion :)

lol that’s amazing

I like both of them, the dubstep-y one or both would be cool included as a Renoise demo tune.

It’d be funny if you released a silent album.

Depeche Mode - Enjoy the Silence (Renoise remix using the RindMod concept as a demo song ?)

http://www.youtube.com/watch?v=1rdfFroO67g