Amongst the myriad of features relating to editing and recording is a very powerful tool known as Elastic Audio. This feature gives us the ability to treat our audio as if it were a rubber band, hence the name, Elastic Audio.
Elastic Audio gives you the ability to stretch audio files, making them playback faster or slower, giving you the ability to match audio tempo and length to your production. This tutorial video shows you how you can use Elastic Audio in your session.
The musical world around us has changed quite dramatically over the decades, and we now find ourselves in a world of endless possibilities when it comes to making music. In the past, it was always guaranteed you had to have a "band" in order to make music, but now with the help of modern technology musicians without a formal "band" can take the reigns and express their creativity without hinderance. One of the easiest ways to help expand your musicality is by the use of sample libraries. No matter what type of music you make, there is a sample library hopelessly devoted to you, yearning for you to make it sing and dance. Take the scenario of a singer/songwriter who needs backing drums, unless you can hire a drummer & studio, your best bet is to utilize a drum sample library. I guarantee you will find really amazing sounding libraries in every genre of music you can imagine. Check out website such ilio.com and bighfishaudio.com to see the variety available catering to all musical styles.
Now that we have found a suitable drum loop library, we can use the Workspace Browser to search for and audition the loops. Window Menu < Workspace:
Once you have found a loop that you like, you can grab that loop and drag it to the Tracks Column to import that file into Pro Tools. By importing audio files this way into your session, Pro Tools handles a couple of things for you, it imports and converts the audio file as needed, it creates an appropriate Mono/Stereo track for that file, names the audio track with the file name, and places the audio file at the beginning of the session.
This is a huge help as it cuts out several steps you would have to do on your own.
The result might look something like this:
Now that you have these loops in your session, the first thing you want to do is to edit the files to make sure they are truly a perfect loop. Don’t worry yet about them matching the tempo of your session, first we need to make sure the loops are correct in their playback. A lot of times loop libraries will include an extra beat forcing you to edit the file to make sure it loops correctly. Trim the end or beginning of the audio loop to make sure what you hear is actually a "perfect" loop. Once we have our loop edited correctly, we can start messing about with Elastic Audio.
The Elastic Audio function is only available in the Edit Window of Pro Tools. It is a track based function that you need to activate track by track as needed. You activate this feature by clicking the Elastic Audio plug-in button located in the track view and selecting the appropriate algorithm you want to use on that track.
Elastic Audio
When you select Elastic Audio, you will see a menu pop-up asking you to choose a specific algorithm for Elastic Audio. There are four main algorithms available for you to choose from depending on what type of material you are working with.
- Polyphonic: General, all-purpose algorithm effective with a wide range of material. Works well for complex loops and material playing multiple pitches.
- Rhythmic: Best suited for drums and percussion material
- Monophonic: Best suited for audio and instruments that play a single note at a time, such as a bass track or vocal
- Varispeed: Link time and pitch changes for "Tape Machine" style speed changes and effects
If you are working with a drum loop the best selection would be the Rhythmic algorithm, and if you have piano parts or guitars, it would be best to use Polyphonic. Choosing the right algorithm make a huge difference in how the process sounds when you apply changes to the audio. In my example, I have chosen Rhythmic for both tracks since they are drum loops. One thing to note is that once you select the algorithm, the audio on the track goes off-line for a moment while Pro Tools analyzes the audio. This analysis depends on how much information is on the track. If you are analyzing an entire song’s worth of audio it might take a bit longer than if you only have a 2 bar loop on the track.
A quick and easy way to conform your loop to the correct session tempo is to right-click on the audio region and select Conform to Tempo from the menu.
This will automatically adjust the tempo of your loop to match the tempo of the session. Quick and painless.
However, if you want more control over the loop and the ability to manipulate the timing of more precise elements within the loop, you can adjust your track display to show you what are called Warp markers. Click the Track View Selector button and select Warp as the view.
Track View Selector
Once you’ve selected Warp as the track view, your audio will now look like this:
Utilizing the Grabber tool, you can now grab and drag each one of the warp markers individually, this is known at a Telescoping Warp. Try it and see how the audio acts like an accordion as you stretch it left or right. This allows you to manipulate the loop length to fit your session needs by hand.
The engineers at Avid have not stopped here with Elastic Audio as they have given you many ways this can be utilized. Remember the Workspace Browser from the beginning of this article? We utilized it to import audio loops into our session. Elastic Audio can also be utilized in much the same way here as it is on the tracks in the session. At the top of the Workspace you will see a small metronome button next to the the elastic audio algorithm button:
You have the option of selecting Elastic Audio to be active in the workspace and to also select which algorithm you want to use. This function allows you to audition and import files into your session that are automatically tempo matched to your session. It also allows you to audition your selections in real time with the session. If you play your session and audition files, Pro Tools is now intelligent enough to not only tempo match the audition, but it also does it in time with the session playing in the background.
I hope you’ve can see the immense power that is available to us all nowadays. These types of functions were only dreamt about a few years ago. But as always, this new technology comes at a price, you have to invest the time and energy to get to know how it works and how you can utilize it in your day to day music making. There is something here for everyone, from the band to the dj, it just take a little practice to make it work for you.
Have fun, make music and we look forward to you joining us in our upcoming Pro Tools Classes at ProMedia Training.
- Mihai Boloni