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Automation

Automation: turning your DAW into an instrument

What is it and Why is it So Exciting?

The argument continues to rage as to which is better for audio - analogue or digital. One of the most compelling arguments for digital over analogue I've seen was contained in a forum post I read many years ago, which read,

"[with digital you have] automation for everything all the time."

Almost every parameter for every effect can be automated in Reaper whenever you want, but what does this mean?

Mostly, you set the volume and pan of your tracks, apply effects to them and leave them alone. Each track sounds the same at the beginning as at the end. With automation however, you instruct your DAW to change something over time, perhaps gradually, perhaps very quickly. This can be used to:

  • Change equalization settings to fix a spectral conflict in the mix that isn't present all the time.
  • bring an instrument forward or back in the mix by automating EQ, reverb and/or volume settings so it has greater or lesser prominence, perhaps in the choruses of a song for example.
  • Create lush, evolving sonic textures for sounscapes, pads etc.
  • Produce the dramatic effects that form the backbone of electronic dance music to transition between parts of the tune such as filter sweeps and tapestop effects.

In short, automation can add a new dimension to your projects, giving you very precise control over everything to produce very subtle or drastic changes. In this article, you will learn one method for doing this.

What are envelopes?

When you apply automation to a parameter, you create what is called an envelope, which is the term given to the graphical representation of the instructions you enter.

When you say, "start the automation here and, over this amount of time, increase the parameter value to this, then hold for this amount of time, then return it to its original value by the time it reaches the end of the project", you have basically plotted a graph with time along the x axis and the parameter's value along the y axis. That's an envelope.

How it's done

We can apply envelopes to takes or tracks, but for this article, we will focus on track envelopes.

The following link will take you to an audio tutorial covering the creation of three different envelopes to design an alien vehicle sound effect and the associated project, so that you can have a look for yourself and experiment.

Even if creating sound effects isn't your field, the principles covered in the demonstration are the same as those governing automation for any purpose.

http://www.cucat.org/aufun/projects/Alien_Vehicle.zip

In addition, below is a brief summary of the essential points and concepts to add automation to a project in Reaper.

Before you can automate anything, you have to make its envelope visible so that you can work on it.

  • Select the track you wish to automate.
  • To make the pan envelope visible, press control alt p. Bear in mind that this key press will not produce any screen reader feedback.
  • You can confirm that you were successful by pressing control l with the track selected. Control l cycles through visible envelopes and selects the one that's focused. Once it's selected, you can make changes.
  • Always remember that, for any envelope you activate, there will be an envelope point already plotted at the beginning of the project that is set to the default value of the parameter in question, usually "center" in this case, unless you have changed the track pan prior to activating the pan envelope.
  • navigate to the place in your project where you want the automated change to begin. If you want the change to start at the beginning of the project, you only need to make a change to the point that is already there, If, that is, you want the parameter to begin at a different value from its default, as in this example, where we want the audio to start at the far left instead of in the center. If you are happy to start at the default value, then you can move straight onto creating your second envelope point.

n.b. If you want your change to begin at the parameter's default value but not at the start of the project, you must find the point where you want the change to start and add an envelope point there. If you don't, the change will slowly take effect between the very start of your project and the point at which you designated a different parameter value.

  • Alt j and alt k navigate you along the timeline backwards and forwards between points of the selected envelope.

Therefore, pressing alt j with the correct track and the pan envelope selected will confirm that you are at point 1.

  • Pressing alt shift e brings up a dialogue box where you can change the attributes of the selected envelope point.

n.b. if you press alt shift e and you do not have an envelope point selected, a new point will be added and the configuration dialogue for it will open.

  • On opening the dialogue, you'll be in an edit box that will allow you to enter a new value for the parameter tied to the envelope. The syntax for writing in this box varies according to the envelope being configured. By default, "center" is written in the pan envelope edit box.
  • Designate the panning you want by writing a percentage followed by either "l" or "r" for left or right. For example, "100%l" will pan the audio all the way to the left.

Having entered the desired value, press enter or tab to "Okay".

  • Navigate to the point in your project where you want the next envelope point. In the case of this example, we want to go to the end of the audio by pressing end.
  • Press alt shift e to insert and configure a new envelope point and type the end value, "100%r" in this case.
  • Having applied your changes, Playing the project from the beginning should allow you to hear the audible results of the graph you plotted. The audio will travel from left to right between the two envelope points.
  • The audio will stay panned hard right until and unless you enter another envelope point after the second and give a new pan value.
  • The steps for configuring a volume envelope are exactly the same, except that, to activate the volume envelope, you press control alt v and can write values in the configuration edit box as positive or negative numbers. n.b. the numbers you enter are absolute as opposed to relative, i.e. if you write "-6" it will put the volume 6 db below unity gain, as opposed to 6 db below your previous point.
  • You can cycle between the volume and pan envelope by pressing control l or control shift l.

Automating an Effect Parameter

Any parameter of any effect that is accessible from the "shift p" dialogue can be automated. All that you need to do is show it as an activated track envelope and then configure it in the usual way.

  • Add the effect to your track. In this example, we are using Reapitch.
  • In the "fx" dialogue, tab to the "param" button and press shift space to activate it, which brings up a context menu.
  • cursor up to "fx parameter list" and open the submenu.
  • Cursor down to "show Track Envelope" and open the submenu.
  • In this submenu, you will find all the automatable parameters for the effect.
  • Press enter on the one you want and then leave the "Fx" dialogue.
  • Pressing control l or control shift l now should take you through the list of envelopes for the selected track, one of which should be the effect parameter.
  • Having selected the effect envelope, you can add points in the usual way with one important qualifier.
  • The syntax for most effect parameter envelope values is a number between 0 and 1.

In some instances, the default parameter value will be "0.500", which represents a midpoint from which the parameter can be increased or decreased. In others, although the default parameter value will be unity gain, you may only be able to increase the parameter by 12 DB for example, but to decrease it to -inf DB. In these cases, the default value in the envelope configuration dialogue will be something different like 0.75.

It is often possible to see what value the number you have entered equates to by navigating between points using alt j and k.

Shaping the Curve

If you follow the steps outlined above exactly, all the changes between envelope points will be linear. In other words the rate of change will remain constant. the audio will be panned from hard left to hard right at so many per cent per second all the way along. However, it is possible to create envelope curves for which the rate of change varies. If you wish to do this, highlight the envelope point that begins a change and press alt shift e.

Pressing shift tab three times will take you to the "shape" combo box, where you can change the curve between two points. By default, the shape is linear as mentioned above.

If you select a square shape, the value of the parameter will not change until the next envelope point is reached. The change will be so sudden that, if you could see the graphical representation, the envelope graph with time along the x axis and parameter value up the y axis would look like a right-angle at that point.

You can also choose shapes that mean the rate of change is faster or slower at the start or end.

Final thoughts

  • If you want to drop an envelope point without opening the configuration dialogue, to designate the start of a change from a value held by a previous envelope point for example simply press control shift i.
  • Envelope points can be adjusted by highlighting them and pressing numpad 2 and numpad 8 to move them down and up a little bit respectively.
  • Multiple envelope points can be selected by pressing alt shift j and k.

Once selected, envelope points can be copied, cut, pasted or deleted in the usual way.

There are many ways to make your effects more dynamic of which this is just one, but using this powerful tool, you can do everything from fading your projects in and out, to making your music more vibrant, to creating bizarre and chaotic soundscapes. Enjoy!

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Page last modified on May 31, 2017, at 05:18 AM