Envelope decoupling is the process where we use an external source to trigger the envelopes for an instrument instead of note on/off events. In that sense we decouple the envelope execution from the MIDI events. The ultimate goal is to produce a sort of more sophisticated gate / arp effect with some characteristics and properties that a Trance Gate effect (Alligator Triple Filtered Gate) cannot achieve.
To be able to do this we need a device that its capable of being triggered by an external source. In this article I'll be using Propellerhead's Reason NN-19 Sampler. Not by chance – as you will later see...
So assuming you have already opened a new Reason document follow these steps:
- Create A New NN-19 Sampler
- Load the “MELCHOIR” patch from the “Synth & Keyboard” Folder. You can of course load any other sound you want for that matter, but I would strongly suggest, for the purposes of this tutorial, to use the specific sounds I'm using.
- Open The Key Editor and write some chords about 1 bar each.
- Locate the L/R cursors around the part where your chords are and hit the Loop Switch.
By now you should be able to hear your chords over and over if you hit play.
Now it's time to apply the decoupling effect.
- Hold down shift and create a Matrix Pattern Sequencer under your sampler. Holding down shift will prevent Reason from auto-routing the newly created device.
- Flip the Rack using tab, and connect the “Gate Out” of the Matrix to the “Gate Input → Amp Env” of the NN-19 Sampler.
We are half way there...
- Now lets change our Amp Envelope Settings. Flip the Rack again and at the front panel of the NN-19 Sampler under the “Amp Envelope”, set the following: Attack: 0, Decay: 43, Sustain: 0, Release: 33
Hit Play. You should now hear a gate effect applied to the pad! What just happened? Under normal circumstances when you hit a key the Amp Envelope is triggered along with the sample. In our case we bypassed that by using the Matrix to control when the Amp Envelope is triggered.
Note that the sample itself does NOT start every time the Amp Envelope is fired. The oscillator of the sampler is still controlled solely by note on/off events.
Try experimenting by creating rhythmical patterns, enabling or disabling steps from the Matrix'es Gate Lane. Also try experimenting changing the Amp Envelope settings. Higher decay and sustain values produce longer tails to the sound which increase the drama and the tension of your pad.
I have created a pattern that looks like :
So far so good. I assume that you've created a pattern you like. Before we go further, make sure the Amp Envelope is set to the settings I gave you above (0, 43, 0, 33)
If you noticed when we flipped the Rack there was also a Filter Env Gate Input. So what would you say if we used that too? Meaning that the Filter Envelope which normally is also triggered by note on/off events was now triggered by another Matrix Device.
Let's do exactly that:
- Shift + Create another Matrix Pattern Sequencer.
- Flip the Rack, But this time connect Matrix'es “Gate Out” to “Gate Inout → Filter Env” of the NN-19 Sampler.
- Flip back to the Rack front. This time we must do some more adjustments. First of all enable the filter if its not already enabled in the sound you're using.
- Lower the cutoff Frequency to 70 and Resonance to 60. Also switch the filter type to LP2.
- Now its time to set the filter envelope. Use these settings: Attack: 0, Decay: 63, Sustain: 0, Release 50. This will make a longer envelope than the one we used for the Amp.
- Finally set the Env Amount of the filter to 23.
- Go to the newly created matrix and silence all steps. Then enable just a few of them, choosing positions from those that you see enabled in the Matrix that controls the Amp Envelope.
Here are my two Matrix-es with the settings I've chosen. Notice that “Matrix 2” which controls the Filter Envelope has a subset of the triggers of “Matrix 1” which controls the Amp Envelope.
Now hit play and give it a listen again …Start's to get interesting right?
Note: f you want, you can use “Tie” steps to keep the gate open, meaning: to let the envelope progress to the sustain phase. Once the gate is closed the Envelope enters the release phase.
Now lets spice up things a bit more.
Go to the Matrix that controls the Amp Env. And switch to curve display.
Flip once again the Rack to view the Rear device panels and change the Matrix curve polarity to Bi-Polar.
Now connect “Curve Out” from the Matrix to the NN-19 “Modulation Input → Osc Pitch”.
Turn the cv trim knob next to the “Osc Pitch” to show exactly 12 on the reading.
Flip back to front panel, and set the switch next to the logo to “Curve”.
Draw some steps, using the middle, the lowest and highest possible step value.
Note: You can of course use the Matrix that controls the Filter Env, or even create a new one for the curve, but I like to use the Matrix for the Amp Env, in order to check my adjustments against the enabled gate triggers.
Here's what I got...
Now hit play. Try adding some echo to the whole patch. I also added some Spread to enhance the stereo image.
Here's a *.reason file with the complete patch.
As you may have already realized, there's so much potential to this. You do not necessary have to use voices or pad sounds. Try using a long evolving soundscape or a tonal texture instead, and see what happens.
Here's another *.reason file that takes this idea a bit further, using a texture with some rhythmical elements and some compression.
Author: Thodoris “Theo” Evangelatos of Quadelectra
Author Specialty: Producer, Engineer, Musician, Song Writer, Rack Extension Developer.