Propellerhead Reason tutorials made by Hydlide

Published on Reason Experts

Modular synth with subtractive synthesis

Published: 2017-09-18

Welcome back to a quick article about a modular synthesizer setup. While I have been working with different concepts and ideas regarding building different styles of modular synths there is one combination I never have dreamed about doing: A Modular build with subtractive synthesis. While in theory it is quite similar as previous build I did regarding using Thor. You can for instance read in my previous concept about setting up a Thor build based on that idea (linked up in the related section at the bottom of this article). I also did similar builds using the NN-XT because it can have its unique options regarding to filters. However, for some reason I never had this idea to do it with a subtractor. And to be honest, it can be quite cool to do it.

Because the setup is quite simple (yet unique at the same time) I am going to briefly touch on this because it is a repeating topic at times based on the same idea. But just throwing this in the air, or against the wall, in case you never thought of it... (as I did)

The concept of a subtractive modular synthesizer

The theory of building a subtractive modular synthesizer is pretty straight forward as it comes to using the subtractor synthesizer in Propellerhead Reason.

Modular build using Subtractive synthesizer

The most obvious thing about it is that can be used as a synth. However, at some level of degree I love to use the oscillators just because of a few things:

  • analog (always has a different offset when loading up the patch)
  • subtractive phase (second mode on market with the minus (-) sign)
  • modulation envelope that can be connected to the subtractive phase (we can use an external source in a modular setup, just saying)
  • lfo 2 connected to the voices by using KDB (keyboard tracking)

These are the most obvious settings that marks the subtractor as a unique synth. Since believe it or not, other synthesizers in the reason rack (native) do not have a subtractive mode.

However, if you compare this synth with what Thor does have well that is a different story. Most obvious thing would be the filters and the shaper.

Using the Subtractor synth as a Thor

Now wouldn't it be quite awesome to make a subtractor that would sound like a Thor, yet have the ability to use the subtractive synthesis methods while using this on a Low Pass Ladder filter with a 6dB per octave. Hey why not?! Since we believe in fairies and orks, anything is possible right.

Modular synthesis using a Low Pass Ladder Filter

For this build I will keep things simple while using Thor as a straight forward Filter unit to pass on the audio. The major benefit in this concept however is that you have 2 different envelopes to your disposal in this case to reshape two different filters at the same time. The first method would be using the Low Pass Ladder filter (in this case) to connect it with the Velocity to Filter Envelope. This will then control the filter frequency on top of the Low Pass Filter.

Modular synthesis filter

The envelope will then cut down, or increase the filter depending on the filter envelope or the inverted switch.

In this case the audio inputs will go through Filter 1 and Filter 2. While everything sits inside a combinator patch, the filters (filter 1, filter 2 and its envelopes) will be triggered when a note is triggered. So in this case I will be abusing this behavior to make use of these two slots. The filter 1 will then go over left (using Filter 3 left in) while the filter 2 will go over right (using filter 3 right in). 

In this particular case we can hook up the subtractor synthesizer directly in to the audio input. While doing so we also have the additional envelopes from the mod env, filter env and amp env to our disposal. This in theory could lead in to some interesting enveloping. Just throwing this on the table as an idea (while in this article I won't really do much with it).

Setting up the modular subtractor synthesizer

Modular Subtractive synthesis

To make the most out of the subtractor in cases like these is using one oscillator on normal phase while having a second oscillator on subtractive phase. In this case you'll get the best of both. At the same time you can use the mix knob to balance between the subtractive sound or the normal sound (take your pick). The best way to reshape the phase is either using the modulation envelope or LFO on Keyboard tracking. The first method is ideal to create subtle movement and waveform changes while the sound progresses over time. The second method is ideal to create a more rapid movement. While ideal using the Keyboard tracking it will also change the moment per note (ideal for chords and such).

There are plenty of different paths you can take while making the subtractor work in a modular set up, let the creativity just flow right through you and you'll be fine.

In conclusion

Sometimes I like these concepts and ideas since it kind of breathes new life in to synthesizer like the gold oldies. While if you listen to the sound output while doing something like this it results in to a fresh breath of air. Sure it may be time consuming from time to time to set these type of things up, but that is also partially the fun of it (otherwise, why else would I be doing this? right ;)).

Just to finish up this article I will share the final patch that also has the Modwheel connected to the Thor Filter patch. Have lots of fun, and I'll type to you later.

Download Modular subtractive synth


Published on Reason Experts
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Published on Reason Experts
Published: 2017-09-18

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