The MONTAGE Envelope Follower

Into percussive arpeggios and drum grooves? This lesson is for you!

(NOTE: The Live Set used in these tutorials can be downloaded here.)

The MONTAGE Envelope Follower allows you to use the output of a Part for modulating selectable parameters of any other Part, enabling you to transfer the movement or rhythm of a Part to other Parts. This way of shaping sound works especially well with percussive arpeggios and drum grooves.

In the Controller Assign box you will find the sources named “Envelope Follower 1 – 18”.
The numbers 1 – 16 are assigned to Parts 1 – 16, while the numbers 17 and 18 are assigned to the A/D parts (L+R).

An Envelope is used to describe a shape. In synthesizers we talk about three main components: Pitch, Timbre (filter), and Loudness (amplitude). There are Pitch Envelopes, Filter Envelopes and Amplitude Envelopes. “Shape” is simply a way to describe how they behave over time: how they start, what they do while they are happening and how they disappear. In the case of the MONTAGE Envelope Follower we are using the Loudness (Amplitude Envelope) of one Part’s sound to create an attack-decay-sustain-release shape for another Part to follow. In other words, the Source Part creates the envelope, while the Destination Part follows that shape.

In our last lesson, we saw an example of how Side Chain Compression uses one sound to replace or “duck” the volume of another. Here, one sound will follow the shape of the other so the pulsing nature of a drum groove can cause the affected sound to exactly follow the rhythmic movement.

PERFORMANCE 14: Envelope Follower

In this example, a Synth Comping sound in PART 2 is used to influence a Synth Pad sound in PART 1. The Synth Comping sound is under the control of an arpeggio’s pulsing techno groove, which triggers the Synth Pad to increase in volume.

For using the Envelope Follower you simply have to make one control assignment for the Part that receives the modulation. In this example, this assignment is found by editing PART 1’s Controllers.

From the main Performance (Home) screen:

• Press [EDIT].
• Press [PART SELECT 1/1].
• Touch “MOD/CONTROL”.
• Touch “CONTROL ASSIGN”.
• Touch the DISPLAY FILTER box to open the LIST VIEW.
• Use the DATA WHEEL to scroll down to “EnvFollow 2” (which means that PART 2 will be referenced as the SOURCE).

Here you can see how the VOLUME is being controlled:

In this example, the Dance pad is shaped by the rhythm of the synth arpeggio of PART 2. Selecting the Source “Envelope Follower 2” and the Destination common “Volume” means that the output of PART 2 modulates the Volume of PART 1.

Temporarily reduce the Ratio to 0. This will remove the influence of PART 2 on PART 1 so that you hear the normal steady sound of the pad sound. As you increase the Ratio toward +63, you’ll hear the increased  influence of PART 2 on PART 1.

To understand this routing, it’s helpful to navigate to the EFFECT itself. In the screenshot above you can see a box next to the DISPLAY FILTER > EnvFollow 2 that is a shortcut box labeled “Edit Envelope Follower”. Touch this to be taken directly to the Envelope Follower:

In the screenshot above, PART 2 is selected and is identified as the SOURCE. The bottom of the screen shows which Parts are feeding into the Envelope Follower as SOURCES to create the “envelope” and which are set to “follow.” From this it is clear that PART 2 (SynCp) is the source, and PART 1 (Pad) is the “follower.” GAIN, ATTACK and RELEASE all help to “shape” the envelope. Experiment by changing the Attack and Release to hear the resultant effect. Gain simply increases the audio output of the source energy.

IMPORTANT NOTE: It should be mentioned here that the screenshot above allows you to edit the GAIN, ATTACK and RELEASE of the item that you have selected as the ENV FOLLOWER source. However, you do not select the SOURCE on this screen – it’s selected on the PART CONTROL ASSIGN screen. So when you change the “PART” on this screen, you are simply looking at (viewing) this Part’s meter – its contribution to the mix. Above, we are looking at the INPUT LEVEL of PART 2. We are also looking at the Envelope Follower Output Level. Changing the GAIN, ATTACK and RELEASE of PART 2 will influence the sonic result. By selecting another Part you can see its audio level; by selecting PART 1, for example, the meters will show what the reaction of PART 1 is and the way it is responding to the shape created by PART 2.

Changing the filter envelope of PART 2 (Element 1) in this example allows you to change the character of the modulation further. The short filter decay (Decay1Time) is especially important for the conciseness for the shape of the modulated Pad sound. If you increase the Decay Time, the intensity rhythmic modulation will be reduced more and more.

The Envelope Follower’s impact can be easily demonstrated in this example by navigating to the Filter EG:

• Go to the main PERFORMANCE (Home) screen.
• Press [EDIT].
• Press [PART SELECT 2/2] to view PART 2 parameters.
• Touch “1” on the bottom line of the screen to view Element 1 settings.
• Touch “Filter”.
• Touch “Filter EG”.

Highlight the TIME parameter “Decay1” in the screen (shown):

Increase the value above 42, then decrease it again to hear what the Envelope Follower is doing as it shapes the overall sound.

The Amplitude Envelope Generator of PART 2 (Element 1) also gives you an opportunity to change the character of the sound. Both the Filter EG and Amplitude EG influence the sound output over time. Filter EG often depends on the Amplitude EG, because if the AEG does not allow for sound to happen, movement in the filter is meaningless. Therefore, if the AEG is not allowing any sound to occur, you will not be able to tell what the Filter is doing – they work together! In other words, the AEG allows for volume change. If there is no volume allowed, you will not be able to hear filter movement – simple as that. Of course, the sound and/or device you choose to generate the source signal will have a great deal of influence of the result.

Extra Credit

VOLUME (amplitude) is a very typical use for the Envelope Follower – and probably the best way to understand how it works – because we are using the loudness of a source to control the loudness of the target, but do not limit your thinking to the obvious or typical. Be sure to use your imagination and don’t be afraid to ask, “I wonder what will happen if …” This is part of the joy of synthesis!

For example, try Element Pan instead of VOLUME as a destination for the Envelope Follower. Now, instead of changing the volume of the target, you can have that audio burst create a movement in position in the mix – so get out your headphones as you send sounds swirling off into the atmosphere!

Things do not all have to happen in a typical pulsating rhythmic way, either; you can create your own custom control motions over entire sections of music. You can offset the timing or extend when and where and how things occur. We can only open the door and let you peek down the long hallway – it is for you to explore and create the music.

Catch up on the previous article in the series – “Mastering MONTAGE 10: Side Chain Modulation” here.

The next article in this series – “Mastering MONTAGE 12: Motion Sequence” is available here.