K404/K504 Assignment 6: More Pro Tools

Explore these Pro Tools features and combine some sounds into a short musical passage (or continue last week's passage).

Note: the info and screenshots below are from an earlier version of Pro Tools.

Creating and Using a Master Fader

To create a Master Fader, use the Track > New command.

Click on the popup menu, but instead of choosing Audio Track, select Master Fader, and makde sure it's a stereo track. This track holds no sound data, but allows you to control the overall volume of your mix. This will create a new track underneath your existing tracks.

The volume for the Master Fader can, like other tracks, be automated via the volume automation envelope.

Insert Effects

To create an insert effect, do this...

Make the Edit Window display inserts: choose View > Edit Window > Inserts.
The edit window should look like this:
Click on the first Insert button (the top button with the small double arrows in it). This brings up the insert menu (below). Select a plug-in:

The plug-in will now appear in the Insert View,

and the plugin itself will appear in a new window:

You can now adjust the settings in the plug-in, and the alterations can be heard while you play. Remember, the processes are realtime, and no alteration is made to the original file. (This is known as non-destructive editing.)

Auxiliary Sends

Certain processes work well as inserts, such as equalization. However, some processes are best applied globally to several, if not all, tracks. One such process is reverberation. While it is conceivable that a separate reverb plug-in could be inserted into every single track, this might be difficult to work with — since you would have to adjust each reverb separately, and it is more computationally expensive.

Instead, we want to use a single reverb processor, and send all tracks to that processor, as you might using an "effects loop" with a traditional analog mixer. Fortunately, this way of working is available in ProTools.

The best way to understand this setup is to think about what happens in a traditional analog mixer.

Below is the ProTools Mix window, with four tracks and a Master Fader. This models a four track analog mixer, with four inputs.

The volume sliders control how much signal is sent from each track to the main output, and the master fader controls how much of the combined signals get sent out of the mixer. All tracks send their signals to the same output. This signal path is called the main signal bus. (A bus is simply a signal path in the mixer.)

Most mixers have additional buses that can route signals to destinations other than the main output. These are called the auxiliary buses. There are usually 2-6 auxiliary buses on a mixer.

They work exactly the same way as the main signal bus: there is a potentiometer that controls how much signal is sent from each track to that particular aux bus, and an auxiliary output which controls how much of the combined signal on that bus gets sent out of the mixer.

The output from the auxiliary bus is then sent to an effects processor, such as a reverb unit. The output from the reverb is then returned to the mixer in either the auxiliary returns (which get sent directly to the master out), or additional input channels.

This configuration allows you to control the level of the original signals (via the volume sliders), the amount that each track/channel is sent to the processor (via the aux send for that track), the amount of total signal that is sent to the processor (via the aux output), and the amount of the processed signal that is sent to the main output (via either the aux returns or the additional input tracks/channels).

In Pro Tools you need to create the auxiliary buses and make all the connections.

Create the auxiliary track: Track > New, and choose Aux Input from the popup menu. Make a mono Aux track. A new track will appear below your current tracks.
Connect your audio track to this auxiliary, thereby creating an auxiliary send.
First you need to display the Sends View in the Edit window (View > Edit Window > Sends A-E). Your Edit window should now display the sends:

At the moment they are not connected to anything.
For each audio track, click on the top send (the top box shown below with a diamond in it) to set which bus it will be sent to. Select bus > Bus 1 (Mono). It doesn't matter which of the buses you choose, as long as you are consistent.

The Edit window should now display the connection of Send 1 to Bus 1:

A new window will also have appeared, which displays the connections, and from which you can control the amount of signal that you send to the bus from the track.
Note that the automation menu for the track now has an additional item, to control the send level and mute status.

This allows you to automate how much signal is sent to the bus.
Connect the Aux track to Bus 1.
First, you need to display both the Inserts and I/O views (View > Edit Window > I/O) for the Aux track. The Edit window now looks like this:
Connect the Aux track to the bus by clicking on the input select button (at the moment, labeled "no input") in the Aux 1 track.

Select bus > Bus 1 (Mono), or whichever bus you connected in the original track, which will display as bold in the menu.
Automate the send levels from your audio tracks. The Edit window should look something like this:

Now when you play your session, you should see the VU meters in both the audio track and the aux track active (depending upon how you set the send level and volume level automation envelopes in your tracks).

Of course, you haven't actually done anything that you can hear. You've created a new bus and sent something to it, but the bus isn't sent anywhere. As noted earlier, one of the most common uses of an auxiliary bus is to send one or more audio signals to an effects processor.

To do this, we need to insert an effect into the aux track. (If we inserted it into the audio track, only that track would have access to it. By inserting it into the aux track, any track that sends to the auxiliary bus will have access to the effect).

Click on the first Insert button in the aux track. This brings up the insert menu (below). Select a plug-in.

The plug-in name will appear in the Insert View,

and the plug-in itself will appear in a new window:

When you play your session, you will now hear the output of the plug-in.

Note that you will hear both the original audio track, and the aux track, unlike when you inserted the process directly in the track. In many cases, the processing done in the aux track will not be apparent, because it will be masked by the original (filtering, for example).

In these cases, you only want to hear the aux track, and not the original signal. While you can Mute the audio track by pressing the mute button, you have effectively lost control over that track. And if you set the output to zero via an automation envelope, you have also lost your auxiliary send.

That's because the default setting for the bus send is post fader. This means that the signal sent to the auxiliary bus is after the track's volume fader. What you what, in this case, is to send the signal before the volume fader, so that you can control the original signal via its track's volume fader, and the amount sent to the effect processor via the auxiliary send level.

To do this, select pre, instead of post, in the bus window, shown below.

If the window has disappeared, click on the Bus 1 button in the track's Send column to make it reappear.

Automating Effects Parameters

Another cool control you have in Pro Tools is automating not only the amount you send to an auxiliary (or insert), but automating parameters in the plug-in itself.

When you select such a plug-in as an insert, it will display an automation button, shown below:

Clicking on this button will bring up the Plug-in Automation window, shown below, which displays which parameters in the plug-in can be automated.

To automate a parameter, select it in the left column, and click the Add>> button. This moves it from the left column to the right one You can select as many parameters to automate as you want. When you are done, click OK.

After selecting a parameter to automate, that slider (or button) will be displayed in green in the plug-in window. Below, the Mix slider is green, since the Wet/Dry parameter was automated. (They are the same.)

The automated parameters will now appear in the automation envelope menu for that particular plug-in. Below, the D-Verb plug-in has its Wet/Dry parameter available. Select it to create an automation envelope.

When drawing the envelope, note that Pro Tools gives you visual feedback for that particular parameter (in the case below, the Wet/Dry mix).