Chapter 41: Elastic Audio. Avid Pro Tools 9.0

Chapter 41: Elastic Audio

Elastic Audio provides track-based Real-Time and Rendered Time Compression and Expansion (TCE) and region-based pitch shifting

(transposition). Pro Tools Elastic Audio uses exceptionally high-quality transient detection algorithms, beat and tempo analysis, and realtime TCE and pitch shifting processing algorithms. Elastic Audio lets you quickly and easily transpose the pitch of audio regions and tempo conform (beat match) audio to the session’s

Tempo map. It also provides an unprecedented degree of control over transient detection and

TCE processing on an event-by-event basis.

With Elastic Audio, Pro Tools analyzes entire audio files for transient events . For example, an event can be a drum hit, a sung note, or chord played by a guitar. These detected events can then serve as control points for warping the audio. Pro Tools can warp (TCE) audio events automatically, such as automatically conforming audio to the session tempo or quantizing audio events, or you can warp audio manually using standard editing tools in Warp view.

Elastic Audio is useful in several common workflows: working with loops, correcting performances, remixing, sound design and special effects, and film scoring.

Working with Loops

If you work with loops, Elastic Audio lets you preview your loops in DigiBase browsers at their native tempo (BPM) or at the session tempo

(BPM). You can even preview the loop while the session is playing back. When you find the loop you like, drag it from the browser and drop it into the session. The loop automatically conforms to the session tempo map and Bar|Beat grid. You can then further manipulate its timing and also transpose the region to match the pitch of other loops in your session.

Correcting Performances

Elastic Audio lets you quantize audio to tighten up a performance or even manually re-align that one note that was played just a little late. Or, you might decide that the performance is excellent, but just a little under tempo. Tick-based

Elastic Audio automatically warps audio to conform to tempo changes. When you change your tracks to tick-based and increase the session tempo, the audio automatically time compresses to match.

Chapter 41: Elastic Audio 857

Remixing

Elastic Audio lets you quickly beat match an entire song to the session tempo and Bar|Beat grid.

You can also transpose regions to match pitch.

Sound Design and Special Effects

Use Elastic Audio to achieve special effects with extreme or widely variable TCE or pitch manipulation. Use the Varispeed algorithm to achieve tape-like effects for speed and pitch change.

Film Scoring

If you are scoring a film scene, use Elastic Audio to fit the music to the required duration. You can even use tempo changes to achieve accelerandos and ritardandos.

Remember, when using tempo adjustments for sessions that include multiple cues, tempo changes may affect the time code position of other cues later on the Timeline.

Elastic Audio is not recommended for pullup and pull-down workflows. Use the

Session Setup window real time pull-up or pull downs, or the presets included with

DigiRack Time Shift or X-Form AudioSuite plug-ins.

Example Elastic Audio

Workflow

In this workflow, you will be introduced to some common Elastic Audio tasks for working with loops:

• Create and configure a new session for this workflow.

• Locate and preview a loop in DigiBase at the session tempo.

• Import the loop at the session tempo on a tick-based, Elastic Audio-enabled track.

• Change the session tempo to change the tempo of the region on tick-based, Elastic

Audio-enabled tracks.

• Quantize the audio to apply a Groove Template to the rhythm.

• Transposition the region to match the pitch of the imported audio to other audio and MIDI in the session.

Create and configure a new session

1 Create a new Pro Tools session.

2 Set the session’s Main Timebase ruler to

Bars|Beats.

3 Be sure to display the Tempo and Meter rulers.

4 Use the default tempo of quarter-note equals

120 BPM.

858 Pro Tools Reference Guide

Locate and preview a loop in DigiBase at the session tempo:

1 Open the Workspace ( Window > Workspace ).

2 Navigate to the folder where you keep your drum loops. Double-click the folder name to open a volume browser of just the folder’s contents.

3 Select the loop you want to preview.

Audition Paths for previewing are selected in the I/O Setup window (Choose Setup >

I/O and click the Output tab).

4 Click the Preview button to preview the loop at its native tempo.

Preview button

Audio Files Conform to Session Tempo button

7 Notice that if the loop was sample-based to begin with, the column to the left of the file name initially indicates that DigiBase is analyzing the file. When the analysis is done a check mark appears in that column, the file’s Duration is now measured in Bars and Beats instead of Minutes and Seconds, the Sample-based icon is replaced by the Tick-based icon, and the detected tempo of the file is displayed in the Tempo column.

Elastic Audio

Analysis icon

Sample-based file icon

Duration

Tick-based file icon

Detected tempo

Preview and Audio Files Conform to Session Tempo buttons in a DigiBase browser

5 Click the Audio Files Conform to Session

Tempo button so that it highlights.

6 Click the Preview button again and the file previews at the session tempo.

Elastic Audio controls and indicators in DigiBase

8 Repeat the preceding steps to preview other loops at the session tempo.

Import the loop at the session tempo:

1 Make sure that the Audio Files Conform to

Session Tempo button is still highlighted. This ensures that the file will be imported as a tickbased, Elastic Audio region and can be conformed to the session tempo.


2 Drag and drop the loop from the browser to the Track List in the session’s Edit window (see

Figure 1 below).

If All Files is selected as the Drag and Drop

From Desktop Conforms to Session Tempo option in the Processing Preferences page, you can also drag and drop audio files from the Desktop and they are imported as tickbased Elastic Audio.

3 One of the following occurs:

• If there are no tracks in the session and the file is tick-based, you are prompted to either import the tempo from the file or use the session tempo. To keep the session tempo and have the loop conform to the session tempo, click Don’t Import .

– or –

• If there are tracks in the session, the file is imported and automatically conformed to the session tempo.

4 A new tick-based audio track is created with the Default Elastic Audio plug-in enabled.

5 Since you chose to not import the file’s original tempo, you will notice that the loop conforms to the tempo map and Bar|Beat grid of the session. A Warp indicator appears in both the region in the track and in the Region List (see

Figure 2 on page 861).

Also in the Region List, notice that there are two regions. One is the sample-based whole file region (the imported source file) and the other is the tick-based Elastic Audio–processed copy.

You can also conform regions on Elastic

Audio-enabled tracks to the session tempo using the Conform to Tempo command (see

“Conform to Tempo” on page 764).

New tick-based,

Elastic Audio–enabled track

Figure 1. Dragging and dropping a tick-based audio file from a DigiBase browser to the Track List


Warp indicators

Sample-based whole-file region

Figure 2. Imported tick-based audio file with Elastic Audio processing

Tick-based Elastic Audio–processed region

Change the session tempo to change the tempo of the region:

1 Change the tempo from the default 120 BPM

to 110 BPM (see “Tempo” on page 759).

Changing the default tempo

2 Notice that since the region is on a tick-based,

Real-Time Elastic Audio-enabled track it automatically conforms to the new tempo.

Quantize audio to apply a Groove Template:

1 Select the region on the tick-based, Real-Time

Elastic Audio-enabled track.

2 Choose Event > Event Operations > Quantize .

3 In the What to Quantize section, make sure

Elastic Audio Events option is selected.

4 From the Quantize Grid pop-up menu, select a

Groove Template.

5 Set any other options.

6 Click Apply .

7 In the following figure, notice that the audio has been quantized according to the selected

Groove Template. In Warp view, you can see that Warp markers have been added at every

Event marker near the Quantize Grid and were used to apply quantization to those events (see

Figure 3 on page 862).


Figure 3. Quantized audio events (Warp markers) in Warp view

Transpose the audio region down a whole-tone:

1 Select the region on the Elastic Audio-enabled track.

2 Choose Event > Event Operations > Transpose .

3 Select the Transpose By option.

4 Enter “–2” semitones.

5 Click Apply .


Elastic Audio Tracks

Any audio track in your Pro Tools session can be

Elastic Audio enabled. Elastic Audio tracks can be either sample- or tick-based. Sample-based

Elastic Audio-enabled tracks let you apply realtime or rendered Elastic Audio processing by editing in Warp view, applying Quantize, and using the TCE Trimmer tool. However, only tickbased Elastic Audio tracks also automatically apply Elastic Audio processing based on tempo changes in the session.

To have all new tracks be tick-based, enable the New Tracks Default To Tick Timebase option in the Editing preferences.

Enabling Elastic Audio Tracks

To enable Elastic Audio on a track:

1 Create a new audio track or choose an existing audio track.

2 Click the track’s Elastic Audio Plug-In selector, and select the Elastic Audio plug-in appropriate to your track material and the results you want from the pop-up menu: Polyphonic , Rhythmic ,

Monophonic , Varispeed , or X-Form

(see “Elastic

Audio Plug-Ins” on page 868).

When creating new tracks by dragging and dropping audio from a DigiBase browser, if the Audio Files Conform to Session Tempo option is enabled, Pro Tools creates tickbased Elastic Audio-enabled tracks regardless of whether the Elastic Audio analyzed file is tick-based or sample-based. If the Audio Files Conform to Session Tempo option is not enabled, Pro Tools creates regular sample-based tracks.

With Pro Tools HD, Elastic Audio is disallowed on voiced tracks. Use dynamic voice allocation for tracks on which you want to use Elastic Audio. (Pro Tools only supports dynamic voice allocation, and cannot specifically allocate individual voices.)

Elastic Audio Plug-In pop-up menu

Any audio regions on the track temporarily go offline while they are analyzed and come back online when the analysis is finished. The waveform for audio regions that are offline for Elastic

Audio analysis appears grayed out.

When recording to a real-time Elastic Audio-enabled track, once recording is stopped, the newly recorded audio temporarily goes offline while it is analyzed and comes back online as soon as the analysis is finished.


3 From the track’s Elastic Audio Plug-In pop-up menu, select Real-Time Processing or Rendered

Processing for Real-Time or Rendered Elastic Audio processing.

Elastic Audio processing can be Real-Time or Rendered. Real-Time Elastic Audio processing is immediate, but it is more demanding of system resources. Rendered

Elastic Audio processing is non-real-time, but is less demanding of system resources. If you are working on a system with limited resources, use Rendered Elastic Audio process-

ing. For more information, see “Real-Time and Rendered Elastic Audio Processing” on page 867.

Creating New Tracks with Elastic

Audio Enabled

New tracks are created with Elastic Audio automatically enabled in the following cases:

• When the Enable Elastic Audio On New

Tracks option is enabled in the Processing

Preferences page (see “Elastic Audio Options” on page 327).

• When dragging and dropping tick-based,

Elastic Audio analyzed files from DigiBase browsers to the Track List or empty space in the Edit window with the Audio Files Conform to Session Tempo option enabled (see

“Elastic Audio on Import” on page 331).

• When dragging and dropping REX or ACID files from the Desktop (if either REX and

ACID Files Only or the All Files option is enabled for the Drag and Drop from Desktop

Conforms to Session Tempo setting in the

Processing Preferences page) or a DigiBase browser (if the Audio Files Conform to Session Tempo button is enabled) to the Track

List or empty space in the Edit window (see

“Importing ACID and REX Files” on page 334).

Disabling Elastic Audio Tracks

To disable Elastic Audio on a track:

1 From the track’s Elastic Audio Plug-In selector, select None – Disable Elastic Audio .

2 If the track had any Elastic Audio-based processing, you are prompted to Cancel , Revert , or

Commit .

Cancel Leaves Elastic Audio enabled on the track.

Revert Removes any Elastic Audio processing, reverts regions on the track to their original duration, and disables Elastic Audio on the track.

Commit Renders and commits any Elastic Audio processing on the track, writes new files to disk, and disables Elastic Audio on the track.

Committed Regions

Regions that are committed, either by disabling

Elastic Audio on a track or by moving a region to a track without Elastic Audio enabled, are written to disk as new audio files. These new audio files include the audio in the region, plus any fades, and also an additional 5 seconds of audio before and after the region, if available.

Disabling Elastic Audio and

Alternate Playlists

Disabling Elastic Audio on a track affects all playlists on the track. All playlists on the track are committed or reverted depending on which option you choose.


Elastic Audio Track Controls

Audio tracks provide controls for enabling Elastic Audio, selecting the Elastic Audio plug-in, and selecting whether Real-Time or Rendered

Elastic Audio processing.

Elastic Audio Track Views

There are two special Track Views for Elastic Audio-enabled tracks: Warp and Analysis.

Elastic Audio

Plug-In selector

Real-Time or

Rendered

Processing indicator

Elastic Audio

Plug-In button

Elastic Audio Track controls

Elastic Audio Plug-In Selector Selects the Elastic

Audio plug-in for Elastic Audio processing (see

“Elastic Audio Plug-Ins” on page 868). You can

also use the Elastic Audio Plug-In selector to disable Elastic Audio processing, and to select either Real-Time or Rendered processing (see

“Real-Time and Rendered Elastic Audio Processing” on page 867).

Elastic Audio Plug-In Button Displays the name of the selected Elastic Audio plug-in. Click the

Elastic Audio Plug-In button to open the Elastic

Audio Plug-In window (see “Elastic Audio Plug-

Ins” on page 868).

Real-Time or Rendered Processing

Indicator Lights when Elastic Audio processing is real-time and dims when Elastic Audio process-

ing is rendered (see “Real-Time and Rendered

Elastic Audio Processing” on page 867).

Track View pop-up menu

Warp View

Warp view lets you manually “time warp” (Elastic Audio process) audio. In Warp view you can create and edit Warp markers. If you are using

Elastic Audio to correct the timing of a performance, or to achieve special effects, work in

Warp view (see “Editing in Warp View” on page 873).

Analysis View

Analysis view lets you edit detected Event markers. In most cases you will not need to use Analysis view. However, with material that does not have clear transients, you may want to work in

Analysis view to add or relocate Event markers, or to delete erroneous Event markers. For example, when using Elastic Audio to correct the timing of a performance, you may need to add, move, or remove Event markers in Analysis view to achieve the highest quality Elastic Audio pro-

cessing (see “Editing in Analysis View” on page 879).


Elastic Audio Analysis

When recording, pasting, moving, or importing un-analyzed audio to an Elastic Audio-enabled track, or when enabling Elastic Audio on an existing audio track, Pro Tools automatically analyzes the audio for transient events. In Waveform view, the waveform initially appears grayed out because regions go offline during

Elastic Audio analysis. Once the analysis is complete, the audio comes back online. Elastic Audio analysis is file-based, which means that even if you are only working with a small region of a large file, the entire audio file is analyzed.

Elastic Audio analysis detects transient events in the audio file. These transient events are indicated by Event markers. Event markers are displayed in both the Warp and Analysis track views. Elastic Audio analysis also calculates the native tempo of the analyzed audio file and its duration in bars and beats.

Elastic Audio analysis data (detected events, tempo, and duration in Bars|Beats) is stored with the file. In DigiBase browsers, analyzed audio files are indicated by a check mark to the left of the file name, and these files display their duration in Bars|Beats, their timebase as ticks, and their native tempo in BPM.

Tempo Detection

Elastic Audio analysis does its best to detect a regular tempo for all analyzed audio. Any audio containing regular periodic rhythm can be successfully analyzed for tempo and duration in bars and beats. Analyzed files in which a tempo was detected are treated as tick-based files. Tickbased files can be conformed to the session tempo for preview and import.

Analyzed files in which no tempo was detected are treated as sample-based files. If there is only a single transient in the file (such as with a single snare hit), no tempo will be detected. Also, longer files that contain tempo changes or rubato, or that do not contain regular periodic rhythmic patterns will probably not have a detected tempo and will be treated as samplebased files.

Event Confidence

Transient events are detected with a certain degree of confidence. The level of confidence is based on the relative clarity of transients.

For example, a drum loop is likely to have clear, sharp transients. These will be detected with a high degree of confidence. However, a legato violin melody may not have clear, sharp transients, so transients will be detected with a lower degree of confidence.

Note that peak amplitude is not the most important measure for event confidence.

The clarity of transients is measured in part by the spectral transition from one moment to the next. This tends to favor higher frequency content in terms of event confidence.

For example, changing the Event Sensitivity in the Elastic Properties window for a selected drum loop results in the clearer transients of the higher frequency hi-hat hits having more event confidence than the less well defined transients of the lower frequency kick drum hits even though kick drum hits have a higher peak amplitude.


Pro Tools is very aggressive with its transient detection in order to detect every possible audio event. Consequently, it is possible to have erroneously detected events. These events will be analyzed with a low degree of confidence and can be filtered out by lowering the Event Sensitivity in the Elastic Properties window (see

“Event Sensitivity Property” on page 883). Filtering out any false transients can result in higher quality Elastic Audio processing.

Conversely, for material with few clear transients, Elastic Audio analysis may not accurately detect audio events, and those detected may be detected with a low level of confidence. You can relocate or add Event markers where necessary

in Analysis view (see “Editing in Analysis View” on page 879).

For example, a slow synth pad may not have clear transients and detected Event markers may be incorrectly located or may have not been detected at all. In Analysis view, you can relocate, remove, and add Event markers as necessary

(such as where the chord changes). Accurately locating Event markers yields better results when applying Elastic Audio processing.

When processing non-rhythmic audio (such as legato strings) with the Polyphonic plugin, reducing the number of Event markers often yields better sounding results. You can either manually remove Event markers in

Analysis view (see “Editing in Analysis

View” on page 879) or lower the Event Sen-

sitivity setting in the Elastic Properties window for the region you want to process (see

“Elastic Properties Window” on page 882).

Real-Time and Rendered

Elastic Audio Processing

Real-Time Elastic Audio processing means that any changes to Elastic Audio processing— whether it be a tempo change or a manual TCE warp, or pitch shifting—take effect immediately. However, Real-Time Elastic Audio processing can be very demanding on your system’s resources. Consequently, you may want to use

Rendered Elastic Audio processing in some cases. With Rendered Elastic Audio processing, when you make a change to Elastic Audio processing, any affected audio regions temporarily go offline, a new “rendered” audio file is generated, and any affected audio regions come back online.

In rendered mode, any change you make is rendered using the original source audio to avoid generational loss from multiple subsequent edits.

To set an Elastic Audio track to Real-Time or

Rendered:

1 Click the track’s Elastic Audio Plug-In selector.

2 From the pop-up menu, select an Elastic Audio plug-in.

3 From the pop-up menu, select one of the following:

• Real-Time Processing

– or –

• Rendered Processing

Select Real-Time processing for tick-based

Elastic Audio processing (such as tempo changes). Rendered audio processing can be useful for sample-based Elastic Audio processing or if you need to save system resources.


Elastic Audio Region

Clip indicators

Elastic Audio Region Clip indicator

Warp indicators

Elastic Audio Plug-In selector and pop-up menu

To toggle between Real-Time and Rendered

Elastic Audio processing, Control-Start-click

(Windows) or Command-Control-click

(Mac) the Elastic Audio Plug-In button.

About Rendered Files

Pro Tools creates temporary files for Rendered

Elastic Audio processing. These files are kept in an auto-created Rendered Files folder in the session folder. Once you commit Rendered Elastic

Audio processing to a track, a new file is written to disk in the Audio Files folder, and the temporary rendered file from which it was created is deleted from the Rendered Files folder.

Elastic Audio Plug-Ins

Pro Tools provides several algorithms for realtime and rendered track-based Elastic Audio processing. The selected Elastic Audio plug-in determines how the audio is processed. Each plug-in uses different algorithms for Elastic Audio processing. Different algorithms are better suited to different types of audio. Select the plug-in whose algorithm is appropriate to the material on the track you want to process.

Elastic Audio plug-ins have their own selector that is only available in the Edit window. You cannot insert Elastic Audio plug-ins on track inserts.

Elastic Audio plug-ins provide few to no adjustable parameters. The adjustable controls, if any, are available in the Elastic Audio Plug-In window. Elastic Audio plug-in parameters cannot be automated.

Region Clip Indicator

(Rendered Processing Only)

Since Rendered Elastic Audio processing is not real-time, it does not report clipping due to Elastic Audio processing in the Elastic Audio plug-in window. Instead, when clipping occurs due to

Rendered Elastic Audio processing, the region displays an Elastic Audio Processing Clip indicator just to the left of the Warp indicator.

To avoid clipping on playback, lower the Input

Gain for the region in the Elastic Properties win-

dow (see “Elastic Properties Window” on page 882).

To open an Elastic Audio Plug-In window:

Click the Elastic Audio Plug-In button.

Elastic Audio plug-in button


Elastic Audio Plug-In Window

Controls

The Elastic Audio Plug-In window provides a set of controls in the window header that are common to all Elastic Audio plug-ins.

Plug-In selector

Track selector

Librarian menu

Settings menu

Clip

LED

Target button

Compare button

Plug-In Settings Select button

Next Setting button

Previous Setting button

Elastic Audio plug-in controls

Track Selector Lets you access any other audio track in the session.

Plug-In Selector Lets you select any Elastic Audio plug-in or disable Elastic Audio.

Plug-In Settings Menu Lets you copy, paste, save, and import plug-in presets.

Plug-In Librarian Menu Recalls Elastic Audio plug-in settings files (presets) saved in the plugin’s root settings folder or in the current session’s Settings folder.

Next (+) and Previous (–) Setting Buttons Lets you select the next or previous preset from the

Plug-In Librarian menu.

You will lose the current plug-in settings if they are not saved before you use the Next and Previous Setting buttons. Always save your plug-in settings as presets using the

Plug-In Settings menu.

Plug-Ins Settings Select Button Accesses the

Plug-In Settings dialog, which lists the presets for the current plug-in. From this list, you can select a new preset, or audition a series of presets.

Compare Toggles between the original saved plug-in settings and any changes you have made to it so you can compare them.

Clip LED Lights red to indicate clipping in the

Elastic Audio processing. Clipping can occur when time compressing audio. If clipping occurs, you can lower the Input Gain in the Elastic

Properties window (“Input Gain Property” on page 884), or attenuate the Default Input Gain

in the Processing Preferences page (see “Elastic

Audio Options” on page 327).

You can undo any Elastic Audio processing and apply an appropriate amount of AudioSuite

Gain reduction, and then try the Elastic Audio processing again. The Clip LED only functions for Real-Time Elastic Audio processing; it does not function for Rendered Elastic Audio processing. For Real-Time Elastic Audio plug-ins, the

Elastic Audio plug-in button on the audio track also turns red to indicate clipping.

For Rendered Elastic Audio processing, clipping is indicated by the appearance of the

Elastic Audio Processing Clip indicator on the region (see “Region Clip Indicator” on page 868).


Target Button When multiple Elastic Audio

Plug-In windows are open, clicking this button selects that plug-in as the target for any computer keyboard commands. Deselecting the Target button lets you open another targeted Elastic

Audio Plug-In window.

Polyphonic Plug-In

The Polyphonic plug-in is a general, all-purpose algorithm that is effective with a wide range of material. For complex loops and multi-instrument mixes, use the Polyphonic plug-in. The

Polyphonic plug-in supports region-based pitch shifting.

The Polyphonic plug-in is the default plugin for previewing and importing from DigiBase browsers or the Region List.

Window

The Polyphonic plug-in provides a single control for adjusting the analysis window size for

TCE processing. Experiment with adjusting the

Window size for different types of material until you achieve the best results. The following table provides some recommended Window sizes for different types of material.

If you frequently work with distinct types of material, you may want to find the best

Window settings for each type of material and save them as plug-in settings for quick and easy recall.

Type of Material

General purpose

Percussive

Pads and other legato material

Recommended

Window Size

30–40 ms

20 ms or lower

60 ms or higher

Elastic Audio plug-in: Polyphonic

Follow

Selecting the Follow option enables an envelope follower that simulates the original acoustics of the audio being stretched. Click the Follow button to enable or disable envelope following.

Rhythmic Plug-In

The Rhythmic plug-in is best suited to material with clear attack transients, such as drums. The

Rhythmic plug-in supports region-based pitch shifting.

Elastic Audio plug-in: Rhythmic


Decay Rate

The Decay Rate control determines how much of the decay from a transient is heard in the processed audio when time stretching. When the

Rhythmic plug-in is selected, any gaps between transients resulting from time stretching are filled in with audio. The Decay Rate determines how much of this audio is heard by applying a fade out rate. Adjust the Decay Rate up to 100% to hear the audio that is filling the gaps created by the time stretching with only a slight fade, or adjust down to 1.0% to completely fade out between the original transients.

Monophonic Plug-In

The Monophonic plug-in is best suited to monophonic material where you want to keep the formant relationships intact, such as with vocals.

The Monophonic plug-in is also well suited to monophonic instrumental lines, such as a bass track. The Monophonic plug-in provides no plug-in specific parameters.

The Monophonic plug-in analyzes pitch as well as peak transients in order to provide higher quality TCE to pitched material.

Consequently, analysis for the Monophonic algorithm takes longer than for the Polyphonic, Rhythmic, and Varispeed algorithms. Also, when switching from another

Elastic Audio plug-in to Monophonic,

Pro Tools reanalyzes any audio on the track to collect the extra analysis data.

Varispeed Plug-In

Use the Varispeed plug-in to link time and pitch changes for tape-like speed change effects, and post production workflows. The Varispeed plugin provides no plug-in specific controls.

Elastic Audio plug-in: Varispeed

Try using Varispeed with Quantize on drum loops for some interesting effects.

Elastic Audio plug-in: Monophonic

Elastic Audio pitch shifting is not supported with the Monophonic algorithm.


X-Form Plug-In

(Rendered Only)

The X-Form Elastic Audio plug-in is a modified version of the standalone X-Form AudioSuite processing plug-in (based on the Radius

®

algorithm from iZotope). The X-Form Elastic Audio plug-in is for Rendered Elastic Audio processing only and cannot process in real-time or as an

AudioSuite plug-in. It provides the highest quality time compression algorithms for music production, sound design, and audio loop applications. Use it to manipulate audio loops for tempo matching or to change vocal tracks for formant correct pitch shifting.

Formant

For audio material with clear formants, enable

Formant to preserve the formant shape of audio when applying TCE processing.

Audio with a fundamental pitch has an overtone series, or set of higher harmonics.

The strength of these higher harmonics creates a formant shape, which is apparent if viewed using a spectrum analyzer. The overtone series, or harmonics, have the same spacing related to the pitch and have the same general shape regardless of what the fundamental pitch is. It is this formant shape that gives the audio its overall characteristic sound or timbre. When pitch shifting audio, the formant shape is shifted with the rest of the material, which can result in an unnatural sound. Keeping this shape constant is critical to formant correct pitch shifting and achieving a natural sounding result.

Elastic Audio plug-in: X-Form

Quality

Select either Maximum or Low (Faster) from the

Quality pop-up menu. Maximum is the slowest processing algorithm, but provides the highest quality results. Low (Faster) produces relatively good results and is much faster than the Maximum setting.


Editing in Warp View

In Warp view, you can manually “time warp”

(TCE) audio to correct or adjust the timing of a performance, or create special effects. In Warp view, you can add, move, and delete Warp markers. Warp markers are used to fix a specific point in the audio (typically a detected transient event) to a specific point in the Timeline. In this way, you can apply detailed and nuanced

“warping” (TCE) of audio events.

Warp view is only available for Elastic

Audio-enabled tracks.

To display Warp view:

1 Click the Elastic Audio-enabled track’s Track

View selector.

2 Select Warp from the Track View pop-up menu.

Elastic Audio Markers in Warp

View

Three types of markers are visible in Warp view:

Event markers, Warp markers, and Tempo

Event–generated Warp markers. Use Event markers and Warp markers as control points for applying Elastic Audio processing.

Event marker

Warp marker Tempo Event

Warp markers

Figure 4. Elastic Audio markers in Warp view

Event Markers

Event markers indicate detected (or manually created) audio events. Event markers are only displayed in Warp view and Analysis view. In

Warp view, Event markers appear as gray vertical lines that do not fully extend to the top and bottom of the track. With the Grabber tool in

Warp view, you can drag Event markers to apply various kinds of warping depending on whether or not Warp markers are present in the region as well. In Warp view, you cannot add, relocate, or delete Event markers. Use Analysis view to edit

Event markers (see “Editing in Analysis View” on page 879).

The display of Event markers is dependent on Horizontal Zoom. If you are zoomed out too far, Event markers are not displayed.

To see Event markers, zoom in.

Warp Markers

Warp markers anchor the audio to a specific point in the Timeline. Warp markers are only displayed in Warp view. In Warp view, a Warp marker appears as a thick black vertical line with a triangle at its base.

To better understand how Warp markers work, think of the audio region as a rubber band, the

Timeline as a ruler, and Warp markers as pins.

Warp markers can be used to pin a specific point of the rubber band (the audio) to a specific point on the ruler (the Timeline). If you pin down one point of the rubber band to one point on the ruler, use a second pin to pin down another point of the rubber band to another point on the ruler, and then place a third pin equally between them on the rubber band, but fix it to a point on the ruler closer to the second pin, the


rubber band will be stretched (or expanded) between the first and middle pins, and relaxed (or compressed) between the middle pin and the last pin.

In Warp view, you can add, relocate (without warping), and delete Warp markers. You can also move a Warp marker to apply Elastic Audio

processing (see “Warping Audio” on page 875).

To add a Warp marker:

In Warp view, do one of the following:

• With the Pencil tool, click anywhere in the region to add a Warp marker at that location. If you click on an Event marker, a

Warp marker is created on top of the Event marker.

• With the Grabber tool, Start-click (Windows) or Control-click (Mac) anywhere in the region to add a Warp marker at that location. If you click on an Event marker, a

Warp marker is created on top of the Event marker.

• With the Grabber tool, if no Warp markers are present in the region, or if Warp markers are only present prior to the location where you want to add a new Warp marker, double-click an Event marker to add a Warp marker on top of the Event marker.

• With the Grabber tool, double-click anywhere in the region where an Event marker is not present to add a Warp marker at that location.

• With the Grabber tool, single-click any

Event marker prior to another existing

Warp marker in the region to add a Warp marker on top of that Event marker.

• With any Edit tool, Right-click anywhere in the region and select Add Warp Marker from the pop-up menu to add a Warp marker at that location. If there is an Edit selection,

Warp markers are added at the selection start and end.

To relocate a Warp marker (without applying warping):

With the Grabber or the Pencil tool, Start-drag

(Windows) or Control-drag (Mac) a Warp marker to a new location.

To delete a Warp marker:


• With the Grabber tool, double-click a Warp marker.

• With the Grabber or the Pencil tool, Altclick (Windows) or Option-click (Mac) a

Warp marker.

• With any Edit tool, Right-click a Warp marker and select Remove Warp Marker from the pop-up menu.

To delete all Warp markers in a selection:

1 In Warp view, make an Edit selection that includes only the Warp markers you want to delete (and none of the Warp markers you want to keep).

2 Do one of the following:

• Press Delete or Backspace on your computer keyboard.

– or –

• With any Edit tool, Right-click the Edit selection and select Remove Warp Marker from the pop-up menu.


Tempo Event–Generated Warp

Markers

Tempo Event–generated Warp markers are not editable and are only displayed to indicate where Elastic Audio processing has been applied to conform the audio to Tempo Events. You will only see Tempo Event–generated Warp markers on tick-based tracks.

If you change the track timebase from ticks to samples, any Tempo Event–generated Warp markers convert to regular, editable Warp markers.

For more information, see “Tempo Changes and Tick-Based Elastic Audio Tracks” on page 763.

To apply Telescoping Warp to a region:


• With the Grabber tool, drag any Event marker that is after the last Warp marker in the region to the left or right to Telescope-

Warp the audio that is after the Warp marker in or out. If no Warp marker is present in the region, one is created automatically at the region start. The region start remains anchored to its location on the

Timeline.

– or –

• With the Grabber tool, Alt-drag (Windows) or Option-drag (Mac) any Event marker that is before the first Warp marker in the region to the left or right to Telescope-Warp the audio that is before the Warp marker in or out. If no Warp marker is present in the region, one is created automatically at the region end. The region end remains anchored to its location on the Timeline.

Warping Audio

In Warp view, you can manually warp audio in three specific ways: Telescoping Warp, Accordion Warp, and Range Warp.

Automation does not follow manual warping of audio regions, including TCE trimming and quantization of Elastic Audio.

However, automation does follow tempo changes on tick-based tracks.

Telescoping Warp

Telescoping Warp can be applied to any audio region before or after a Warp marker as long as no other Warp marker precedes or follows it accordingly. The audio can be on a sample- or tickbased track. Telescoping Warp is especially useful for adjusting audio files to match the session tempo map and Bar|Beat grid.

Before and after warping, applying Telescoping Warp with the region start fixed


Workflow Example

Beat match a song to the session tempo and

Bar|Beat grid using Telescoping Warp:

1 Make sure the Main Timebase ruler is set to

Bars|Beats.

2 Set the default tempo and meter.

3 Select Grid mode.

4 Import a song, or any other longer audio file from a DigiBase browser.

5 Make sure that Elastic Audio is enabled on the track.

6 Select Warp view.

7 Make sure there are no Warp markers present on the region. If necessary, delete any exisiting

Warp markers.

8 With the Pencil tool, add a Warp marker at the bar 1 downbeat location within the region.

9 With the Grabber tool, drag the single Warp marker to the bar in the Timeline where you want the downbeat of the audio file to start.

10 Drag the Event marker on the downbeat of bar 2 of the region to Telescope warp the audio such that the Event marker matches the corresponding bar number in the Bars|Beats ruler.

11 If the region’s tempo varies, add a Warp marker to the next downbeat location at the tempo change and repeat the preceding steps.

To apply Accordion Warp to a region:

1 In Warp view, add a single Warp marker at the point in the region that you want to remain fixed on the Timeline.

2 With the Grabber tool, drag any Event marker that is before or after the single Warp marker to the left or the right.

Before and after warping, applying Accordion Warp to a region around a fixed point

Range Warp

Range Warp applies Elastic Audio processing between two fixed points in a region. To apply

Range Warp, there must be at least two Warp markers present in the region.

To apply Range Warp within a region:

1 In Warp view, add a Warp marker at the first point that you want to fix to the Timeline.

2 Add another Warp marker to the end point that you want to fix to the Timeline.

Accordion Warp

Accordion Warp applies Elastic Audio processing on both sides of a singe Warp marker in a region. This lets you expand or compress the audio equally on both sides of a fixed point.

Accordion warp is useful for audio files where the downbeat occurs in the middle of the region.


3 With the Grabber tool, drag an Event marker between the two Warp markers to the left or right. A Warp marker is added on top of the

Event marker and the audio is compressed or expanded on either side of the dragged marker while the audio outside the bounding markers remains unaffected.

5 With the Grabber tool, drag any of the Warp markers within the Edit Selection to the left or the right.

Before and after warping, applying Range Warp between two Warp markers in a region

Range Warp with an Edit Selection

Pro Tools lets you apply Range Warp between bounding Warp markers, but keeps the timing intact between other Warp markers within an

Edit selection.

To apply Range Warp with an Edit Selection:

1 In Warp view, add a Warp marker at the first point that you want to fix to the Timeline.

2 Add another Warp marker to the end point that you want to fix to the Timeline.

3 Add any number of Warp markers in between.

4 With the Selector tool, make an Edit selection that includes the Warp markers in between the bounding Warp markers.

Before and after warping, applying Range Warp to a selection between bounding Warp markers

Elastic Audio processing is only applied to the audio between the bounding Warp markers and the first and last Warp markers in the Edit Selection. All audio between the first and last Warp markers in the Edit Selection maintain their relative timing.

Individual Range Warp

Individual Range Warp applies warping to a single audio event in relation to the adjacent audio events.

To apply Individual Range Warp:

1 In Warp view, with the Grabber tool, Shiftclick a Warp marker or an Event marker. If not already present, Warp markers are automatically created on the adjacent Event markers.

2 Drag to the left or right to warp the clicked event.


To toggle the display of the Warp indicator in

Elastic Audio regions:

Select or deselect View > Region > Processing

State .

Before and after warping, applying Individual Range

Warp

Warped Regions

Regions that have been warped either manually or automatically by tempo change, quantization, or pitch shifting display a Warp indicator in the upper right-hand corner of the region.

This indicator is visible in any track view. Since unwarped regions can reside on Elastic Audioenabled tracks, regions on Elastic Audio-enabled tracks do not necessarily display the Warp indicator. The Warp indicator only indicates that

Elastic Audio processing has been applied to a region.

Out of Range Processing

Pro Tools lets you apply extreme amounts of

Elastic Audio processing. However, at such extremes, it is possible to go out of the selected

Elastic Audio plug-in’s processing range. When this happens, it is possible that not every sample will be processed correctly and you may encounter audio drop outs.

The valid range for Elastic Audio TCE processing is 1/4x to 4x for all Elastic Audio plug-ins except

X-Form, which supports 1/8x to 8x. TCE less than or greater than these ranges is effectively

“out of range.”

When out of range processing occurs, the section of the audio region that is out of range turns red. You can still apply Elastic Audio processing, but you are warned by the color change that the TCE factor is out of the normal range of

Elastic Audio processing.

Warp indicator in a region in Waveform view

Displaying the Warp Indicator

The Warp indicator for Elastic Audio regions can displayed or hidden.

TCE Factor is out of range (in red)

The TCE Factor in the Elastic Properties window supports extreme ranges from

1–9999%. However anything outside of

25–400% will be “out-of-range” and will be displayed in red.


Removing Region Warping

If you have applied any warping to a region, you can remove warping and revert the region to its original duration. This can be useful if you are not satisfied with the results and want to revert to the pre-warped region. Warp markers are not deleted when applying the Remove Warp command, but any warping is undone.

To remove region warping:

1 Select the region for which you want to remove warping.


• Choose Region > Remove Warp .

– or –

• With any Edit tool, Right-click the region and select Remove Warp from the pop-up menu.

Remove Warp can only be applied to regions and cannot be applied to region groups. To unwarp region groups you must first ungroup the region, then apply Remove

Warp to the underlying regions, and then regroup those regions.

Edit Groups and Warp Editing

Elastic Audio-enabled tracks can be included in

Edit Groups. For Elastic Audio-enabled tracks that are part of an Edit Group, applying Elastic

Audio processing on one track likewise applies it to all other tracks within that Edit Group.

If corresponding Warp markers are not already present on Elastic Audio-enabled tracks that are part of an Edit Group, new Warp markers are created on those tracks when you add or move a

Warp marker on any track that is part of the Edit

Group.

Editing in Analysis View

In Analysis view, you can add, move, promote, and delete Event markers. Usually, Pro Tools accurately detects all the transient events (Event markers) in an audio file and you will not need to work in Analysis view. However, Pro Tools may not accurately detect every audio event or may erroneously detect audio events with some types of audio material. This is especially true for audio without clear transients, such as legato strings, melismatic vocals, or soft synth pads.

Use Analysis view to manually correct the presence and location of Event markers. The accurate identification of audio events yields the best results when applying Elastic Audio processing.

To display Analysis view:

1 Click the Elastic Audio-enabled track’s Track

View selector.

2 Select Analysis from the Track View pop-up menu.

Analysis view is only available for Elastic

Audio-enabled tracks.

In Analysis view, you can only edit Analysis markers using the Edit tools. You cannot use the Edit tools for any region editing.

Switch to Warp or Waveform views for region-based editing capabilities with the

Edit tools.

When manually editing Analysis markers,

Pro Tools writes temporary Elastic Audio analysis files (.aan) to the session’s

Rendered Files folder. Any unused temporary analysis files are purged when you close the session.


Adding Event Markers

To add an Event marker:

In Analysis view, do one of the following:

• With the Pencil tool, click at the location where you want to add an Event marker.

• With the Grabber tool, double-click at the location where you want to add an Event marker.

• With the Grabber tool, Start-click (Windows) or Control-click (Mac) at the location where you want to add an Event marker.

• With any Edit tool, Right-click at the location where you want to add an Event marker and select Add Event Marker from the pop-up menu.

Adding an Event marker with the Pencil tool

Moving Event Markers

To move an Event marker:


• With the Pencil tool, drag the Event marker to a new location.

– or –

• With the Grabber tool, drag the Event marker to a new location.

Promoting Event Markers

Event markers are detected with relative degrees of confidence (between 1% and 100%). You can filter out extraneous Event markers by adjusting the Event Sensitivity setting in the Elastic Properties window; event markers with the least confidence are filtered out first. However, some significant events may not be recognized with a high degree of confidence. In this case, you may want to promote the Event marker to ensure that it is not filtered out when reducing the

Event Sensitivity setting. Promoted Event markers, like manually created or moved Event markers, have 100% confidence.

To promote an Event marker:

In Analysis view, with the Grabber or Pencil tool (or with the Smart Tool in the bottom half of the track), single-click the Event marker you want to promote.

Promoted Event markers look the same as detected Event Markers. To see all Event markers that have 100% confidence, reduce the Event Sensitivity setting in the Elastic

Properties window (see “Event Sensitivity

Property” on page 883).

Moving an Event marker


Deleting Event Markers

To delete an Event marker:


• With the Pencil tool, Alt-click (Windows) or Option-click (Mac) the Event marker you want to delete.

• With the Grabber tool, Alt-click (Windows) or Option-click (Mac) the Event marker you want to delete.

• With the Selector tool, make an Edit selection that includes any Event markers you want to delete and press Delete or Backspace on your computer keyboard.

• With the Selector tool, make an Edit selection that includes any Event markers you want to delete, Right-click the selection, and choose Remove Event Marker from the pop-up menu.

Elastic Properties

Each region on an Elastic Audio-enabled track has specific Elastic Audio properties (such as tempo, meter, TCE factor, Input Gain, and Pitch

Shift).

The Elastic Properties window lets you view and change the properties for selected regions. For example, you can reduce the Input Gain for

Elastic Audio processing to avoid clipping that can occur during processing.

From the Elastic Properties window, you can also filter Event markers for Elastic Audio regions on tick-based tracks. Filtering Event markers can result in better quality Elastic Audio processing of material with ambiguous transients.

Deleting an Event marker with the Pencil tool

Edit Groups and Event Editing

Elastic Audio-enabled tracks can be included in

Edit Groups. For Elastic Audio-enabled tracks that are part of an Edit Group, editing Event markers on one track likewise applies to all other tracks within that Edit Group.

To view the Elastic Properties for a region:

1 Select a region on an Elastic Audio-enabled track. The track can be either sample- or tickbased.


• Choose Region > Elastic Properties .

– or –

• Right-click the region and choose Elastic

Properties .

Press Alt+5 (Windows) or Option+5 (Mac) on the numeric keypad to open the Elastic

Properties window.


Elastic Properties Window

The Elastic Properties window displays information about Elastic Audio processing and analysis for one or more regions. You can also use the

Elastic Properties window to adjust Elastic Audio processing and analysis data.

There are different Elastic Properties available in the Elastic Properties window, depending on whether the track is tick-based or sample-based.

If the track is sample-based, a reduced set of Elastic Audio Properties are displayed.

Elastic Properties, tick-based

Elastic Properties, sample-based

Region Property

The Region property in the Elastic Properties window displays the name of the region and indicates whether or not the region is on a tick or sample-based track. If more than one region is selected, the number of selected regions is displayed. If regions on both tick and sample-based tracks are selected, only the reduced set of properties are displayed.

Source Length Property (Tick-

Based Tracks Only)

The Source Length property in the Elastic Properties window displays the length of the region based on the source file in bars and beats. If the length of the source file was analyzed incorrectly, you can change it.

To change the Source Length of a region:

1 Open the Elastic Properties window for the region.


• Type the correct bar, beat, and tick values in the Source Length field.

• If the duration was incorrectly analyzed as being half the duration of the source file, click the x2 button.

• If the duration was incorrectly analyzed as being twice the duration of the source file, click the 1/2 button.

Changing the duration of a region on an

Elastic Audio-enabled track using the TCE

Trimmer tool updates the Source Length in the Elastic Properties window.

Source Tempo Property (Tick-

Based Tracks Only)

The Source Tempo property in the Elastic Properties window displays the average tempo of the source file, which is calculated based on the detected transient events and the length of the file.

If the tempo of the source file was analyzed incorrectly, you can change it.


To change Source Tempo of a region:


2 Select the correct note value for the beat from the Tempo Resolution pop-up menu. For example, if the source file is in 5/8, select 1/8 note.


• Type the tempo in the Source Tempo field.

• If the tempo was incorrectly analyzed as being half the tempo of the source file, click the x2 button.

• If the tempo was incorrectly analyzed as being twice the tempo of the source file, click the 1/2 button.

Meter Field (Tick-Based Only)

Elastic Audio analysis does not calculate meter and assumes all files are in 4/4. If you work with meters other than 4/4, use the Meter property to correctly identify the source meter.

To change Meter of a region:


2 Click in the Meter nominator field and type the correct number of beats per measure. For example, if the region is in 3/4, type 3.

3 Click the Meter denominator field and type the correct note value. For example, if the meter is in 6/8, type 8.

TCE Factor Property

The TCE Factor property in the Elastic Properties window displays the percentage of change applied to the source file. On tick-based tracks, this property is display only and cannot be edited.

On sample-based tracks, you can change the

TCE Factor to apply TCE to the region. The percentage of the TCE factor is always calculated in relation to the source file. The TCE Factor value turns red when Elastic Audio processes exceeds

the valid range (see “Out of Range Processing” on page 878).

Event Sensitivity Property

The Event Sensitivity property in the Elastic

Properties window lets you filter Event markers based on the analysis confidence level. The confidence level for any detected transient event is based, in part, on the clarity of the transient. For example, if the file is a drum loop, loud accented hits will be analyzed with a higher degree of confidence than a soft, unaccented hit.

The Event Sensitivity acts like a threshold for showing only the transient events that were detected with a high degree of confidence. In

Warp or Analysis track views you will see the number of Event markers decrease or increase as you lower or raise the Event Sensitivity.

Lowering the event sensitivity can help reduce the number of erroneously detected transients.

In turn, this can result in better sounding Elastic

Audio processing. Pro Tools preserves the detected transients when applying TCE in order to avoid flamming and granulation of the transients. Consequently, false transients are also preserved and the resulting sound quality can be less than desirable. If you are working with audio material that does not have clearly defined transients, you may want to lower the Event

Sensitivity in the Elastic Properties, or you may want to even edit the Event markers in Analysis view.

If lowering the Event Sensitivity results in filtering out important Event markers, you can promote those Event markers in Analysis view (see

“Promoting Event Markers” on page 880).


For REX files, Pro Tools converts the slices as Events with 100% confidence. Consequently, setting the Event Sensitivity from

99% to 1% does not filter out any events based on slices. However, if you set the

Event Sensitivity to 0%, all markers are filtered out regardless.

Pitch Shift Property(Polyphonic,

Rhythmic, and X-Form Only)

The Pitch Shift property in the Elastic Properties window lets you pitch shift whole regions on

Elastic Audio-enabled tracks using the Polyphonic, Rhythmic, and X-Form plug-ins. You apply real-time or rendered pitch shifting in semitones and cents by +/– 2 octaves.

When you change the Event Sensitivity property, Pro Tools writes temporary filtered Elastic Audio analysis files (.aan) to the session’s Rendered Files folder. Any unused temporary filtered analysis files are purged when you close the session.

Reset Button

Click the Reset button in the Elastic Properties window to reset event analysis data for the region to match the original file. The Event Sensitivity property is reset to 100%.

Elastic Audio Region-Based

Pitch Shifting

(Polyphonic, Rhythmic, and X-Form Only)

In addition to Pro Tools Elastic Audio time compression and expansion capabilities, you can also change the pitch of whole audio regions in semitones and cents in the range of +/– 2 octaves.

Elastic Audio pitch transposition is not supported with the Monophonic algorithm.

However, if you switch to the Monophonic plug-in after pitch shifting with another plug-in, the pitch metadata for the region is maintained.

Input Gain Property

It is possible to encounter clipping when time compressing audio. Real-Time Elastic Audio plug-ins provide a Clip indicator to let you know when clipping has occurred and the Elastic Audio plug-in button turns red. Rendered Elastic

Audio regions display a Clip indicator on the region when clipping has occurred (see “Region

Clip Indicator” on page 868).

If you encounter clipping when processing Elastic Audio, use the Input Gain property in the

Elastic Properties window to attenuate the gain of the audio signal before it is processed.

Elastic Audio pitch transposition cannot be applied to looped regions or region groups.

To pitch shift a region:

1 Make sure the region, or regions, you want to pitch shift are on Elastic Audio-enabled tracks

(using the Polyphonic, Rhythmic, or X-Form algorithm).

2 With the Grabber or Selector tool, select the audio region you want to pitch shift. Only regions that are completely selected will be affected.



4 Adjust the Pitch Shift settings up (“+”) or down

(“–”) by an amount in semitones and cents.


• Adjust the Transpose By settings by an amount in semitones and cents.

– or –

• Adjust the Transpose From and To settings by an amount in Semitones and Cents.

The Transpose All Notes To and the Transpose In Key settings can only be applied to

MIDI notes. When only audio regions are selected, these options are unavailable.

5 Click Apply .

Elastic Properties window

To transpose the pitch of an audio region in the

Transpose window:

1 Make sure the region, or regions, you want to

Transpose are on Elastic Audio-enabled tracks

(using the Polyphonic, Rhythmic, or X-Form algorithm).

2 With the Grabber or Selector tool, select the audio region you want to transpose. Only regions that are completely selected will be affected.

3 Choose Event > Event Operations > Transpose .

Varispeed and Pitch Shifting

When using the Varispeed algorithm, pitch transposition and time compression/expansion are always linked. If you apply pitch transposition to an audio region using the Polyphonic or

Rhythmic algorithms, that transposition data is stored in the metadata for the region. Consequently, if you then switch to Varispeed, change the TCE factor, and then switch back to the original Elastic Audio algorithm, the region will revert to the original amount of pitch shifting while maintaining the amount of time compression/expansion applied by the Varispeed algorithm.

Event Operations, Transpose


Removing Region Pitch Shifting

If you have applied any pitch shifting to a region, you can remove pitch shifting and revert the region to its original pitch. This can be useful if you are not satisfied with the results and want to revert to the pre–pitch shifted region.

To remove region pitch shifting:

1 Select the region for which you want to remove warping.


• Choose Region > Remove Pitch Shift .

– or –

• With any Edit tool, Right-click the region and select Remove Pitch Shift .

Remove Pitch Shift can only be applied to regions and cannot be applied to region groups. To remove pitch shifting from region groups you must first ungroup the region, then apply Remove Pitch Shift to the underlying regions, and then regroup those regions.

AudioSuite Processing and

Elastic Audio Regions

Real-Time Elastic Audio processing is non-destructive. However, since AudioSuite plug-ins process the entire region and write a new audio file (or actually apply destructive processing), when applying AudioSuite processing to regions on Elastic Audio-enabled tracks, any Elastic Audio processing is rendered first, the rendered file is then processed by AudioSuite, and the resulting new audio file is analyzed for Elastic Audio processing.


Moving Elastic Audio Between Tracks

Pro Tools analyzes, conforms, and commits audio in different ways when moving audio regions between tracks with Elastic Audio enabled and tracks without Elastic Audio enabled. The following table shows the different results for moving regions between real-time Elastic Audio-enabled tracks, Rendered Elastic Audio-enabled tracks, and audio tracks without Elastic Audio.

Moving Elastic Audio between tracks

From To Result

Real-time Elastic

Audio–enabled track

Real-time Elastic


Rendered Elastic


Rendered Elastic


Audio track (no Elastic

Audio)

Audio track (no Elastic

Audio)

Pitched Elastic


Rendered Elastic

Audio–enabled track audio track (no Elastic

Audio)

Real-time Elastic


Audio)

Real-time Elastic


Rendered Elastic


Audio)

Render region with destination track’s Elastic Audio plugin

Render region with source track’s Elastic Audio plug-in and commit the region to the destination track

Apply real-time Elastic Audio processing using the destination track’s Elastic Audio plug-in

Commit to track

Calculate Elastic Audio analysis and apply real-time Elastic Audio processing using the destination track’s Elastic

Audio plug-in

Calculate Elastic Audio analysis and render the region using the destination track’s Elastic Audio plug-in

Render region pitch shift with source track’s Elastic

Audio plug-in and commit the region to the destination track

Regions that are committed, either by disabling Elastic Audio on a track or by moving a region to a

track without Elastic Audio enabled, are written to disk as new audio files (see “Committed Regions” on page 864.)


Fades and MicroFades

Fades and Elastic Audio

Processing

When applying fades to warped regions (regions that have been processed by Elastic Audio), the audio selected for the fade is first rendered and then the fade is generated based on the rendered audio file. While you can create fades and crossfades on regions on Elastic Audio-enabled tracks, neither Real-Time nor Rendered Elastic

Audio processing can be applied to fades. Consequently, fades always retain their absolute duration and fades must be recalculated after any

Elastic Audio processing has been applied to the underlying audio.

For example, if you change the session tempo, a region on a tick-based Elastic Audio-enabled track will change its duration (in minutes and seconds) to match the new tempo, but any fades that are part of that region do not change duration. The underlying audio is processed to match the tempo change, then it is rendered, and then the fade is regenerated. Even though the underlying audio changes, the absolute duration of the fade does not.

In Warp view, you will notice that Event markers never appear in fades and that Warp markers cannot be added within fades. As a general rule, apply fades to regions on Elastic Audio-enabled tracks only after you have finished any manual warp editing.

Region groups that contain regions with fades are not allowed on Elastic Audio-enabled tracks.

Microfades

Real-time Elastic Audio processing is not completely deterministic. Consequently, depending on where you start playback, the part of a region being played might actually be a few samples longer or shorter. When fades or crossfades are applied to warped regions, the audio waveform at the boundary between the (real-time) region and the (rendered) fade may not actually be continuous.

For example, if there are two butt-spliced regions on a Real-Time Elastic Audio-enabled track, Elastic Audio processes them separately even though they are contiguous on the track.

As a result, the audio may not really be contiguous after Elastic Audio processing and there may be an audible pop when playing back across the transition between the two regions.

To help compensate, Pro Tools applies microfades to region boundaries on Real-Time Elastic

Audio-enabled tracks. Microfades are small realtime fades at region boundaries intended to mitigate artifacts across region boundaries, or between an Elastic Audio processed region and a rendered Fade file. Microfades are very short; they are only about 1.5 milliseconds long (64 samples at 44 kHz, 128 samples at 96 kHz, and

256 samples at 192 kHz).


Approximate Waveforms

Another consequence of Real-Time Elastic Audio processing is that the drawing of the waveforms is only approximate. For example, if you bus record a Real-Time Elastic Audio processed track, you will notice that the Waveform on the source track does not necessarily exactly match the recorded track. However, be assured that what you hear is an accurate rendition of the

Real-Time Elastic Audio processing even if the waveform drawing on the source track is only approximate.

Elastic Audio Preferences

The Elastic Audio settings in the Processing Preferences page determine which Elastic Audio plug-in is used for preview and import, and whether or not new tracks are created with Elastic Audio enabled using the selected default plug-in.

Elastic Audio preferences

Default Plug-In Lets you select any Real-Time

Elastic Audio plug-in as the default plug-in for previewing and importing Elastic Audio. The selected default Elastic Audio plug-in is also used when new tracks are created with Elastic Audio enabled. The Elastic Audio Plug-In selector in

DigiBase browsers inherits the selected Default

Plug-In setting. Likewise, changing the selected plug-in in DigiBase browsers updates the selected Default Plug-In setting in the Processing

Preferences page.

Default Input Gain Lets you attenuate the signal input to Elastic Audio plug-ins by 0 to –6 dB for preview and import. If you experience clipping due to Elastic Audio processing during preview or after import, you may want to set the Default

Input Gain to slightly attenuate the audio signal input for Elastic Audio processing. This preference also applies to any audio imported to an

Elastic Audio-enabled track.

If you commit any regions on a track (by disabling Elastic Audio on the track) that were imported with Input Gain, their region-based In put Gain is reset to 0.

The Elastic Properties window inherits the Default Input Gain preference. To apply further region-based Input Gain for Elastic Audio processing, select the region and adjust the Input Gain setting in the Elastic Properties window (see

“Elastic Properties Window” on page 882).

Enable Elastic Audio on New Tracks When selected, new tracks are created with Elastic Audio enabled. The selected default Elastic Audio plugin is used.

If the Enable Elastic Audio on New Tracks option is selected, you may want to also select the New Tracks Default to Tick Timebase option in the Editing Preferences page.



No results