Essential Avid “Digidesign Pro Tools” Session Management Basics – File Structure

For many Pro Tools users the term file structure may sound dry and uninspiring. But take my word for it – everyone who uses Pro Tools should know this stuff. After all, you’re talking about looking after the music you work so hard to create.

The Basic Idea

When we say file structure what we’re really talking about is how Pro Tools stores and organizes all of the files used by a session on your hard drive.

It is not a complicated thing. But not knowing about file structure may cause you to accidentally delete important audio or find your backups missing essential elements from your session.

Everything goes in the Session Folder

When you create a New Session, the software automatically creates a folder named after your session. This is referred to as the Session Folder. You can think of this session folder as the master folder associated with each particular session because all the files that Pro Tools automatically creates throughout the duration of a session are going to be stored in it.

Audio Files

This is what I’d call a vital folder (and that’s an understatement). Any audio that you record or import into Pro Tools will reside in this folder.

If you process audio using AudioSuite plug-ins, it will be stored here too.

If this folder gets misplaced or worse – deleted, it could mean your entire session is toast and you’ll need to start again from the ground up. Right down to setting up the mics again and recording the first note. So be careful.

Naming Audio Files

As a side note. One of the most common session management problems you will encounter is caused by simply not naming your audio files.

The best practice is to name the audio tracks before recording on them. That way the naming of the audio files will be done automatically for you. It will save you having to look through a hard drive full of files with names like “audio_01_01”, and “audio_27_02_11”.

Fade Files folder

Fade files are stored in the Fade Files folder.

Did you know that fades and crossfades in Pro Tools are actually unique audio files? When you apply a fade or crossfade to audio in Pro Tools, the software generates a small audio file, called a Fade File. A fade file is a small audio file of only the faded, or crossfaded portion of audio.

This is smart because it means you can go back later and edit the fade or even delete the fade – all without ever changing the original audio file.

By storing Fades and Crossfades as separate audio files, Pro Tools is able to load sessions with a ton (ie: hundreds or thousands) of fades much faster than if it had to regenerate them each time you load the session.

Regenerating Fade Files
If for some reason you accidentally deleted the fade files folder and it’s contents, Pro Tools would still be able to regenerate the missing fade files. All of the information necessary to regenerate the fades is contained in the Pro Tools session file.

Session file (.ptf)

The.ptf (Pro Tools Session File) IS the session. It contains a map to all of the media (audio and video) files used in the session and all of the editing, mixing, midi, plug-in, and session settings. It really is the brain of the session.

Every single session detail – from automation breakpoints to track colors to midi performances to track heights and region definitions. memory locations, track names – almost everything other than raw audio and video files is stored within this document.

The great thing about Pro Tools session files is that they take up relatively little memory (from 20kb up to a few MB) and can easily be copied and renamed. That makes it easy to create as many alternate versions of a session as you want.

Whether it’s to experiment with a different arrangement or a different mix, you can just use the Save As command to save a variation of the current.ptf file to the session folder. Each new version of the session file will still utilize the same Audio and Fade Files folders.

Region Groups folder

If you’re using Region Groups in your session, you may decide to use the Export Region Groups feature (in the Regions drop down menu), Pro Tools will create a.rgrp file and save it in this folder.

To avoid confusion: the software does not store all Region Groups from your session in the Region Groups folder. By default, Region Groups are saved as part of the session file (.ptf).

Instead the Region Groups folder is only for the Region Groups that have been manually Exported by you.

WaveCache file (.wfm)

The WaveCache file has one purpose: it stores the information that has been calculated and stored to draw the waveform overviews that you see in the Edit Window. Since the data is simply loaded (not re-computed), Pro Tools is able to load your sessions that much quicker.

Like fade files, if the WaveCache file is deleted, Pro Tools will be able to recalculate and draw the waveform overviews. But again like fade files, the WaveCache file makes the loading a session much faster.

MIDI Files folder

Pro Tools has features for sending MIDI tracks from your session to Sibelius or G7 notation software (if you happen to have either one). If you use the Send to Sibelius command (File > Send To Sibelius… ) It will send the exported files to the MIDI Files folder within the Session Folder.

Rendered Audio Files folder

If you’re using Elastic Audio, you’ll have the option of using either Rendered Processing or Real-Time processing. If you choose Rendered Processing, the software puts the rendered audio files in the Rendered Files folder.

If you Commit to a rendered audio file that is currently being used in the session, Pro Tools will convert it into a new audio file and place it in the Audio Files folder. Then it will delete the rendered file from the Rendered Files folder.

Once again, this highlights the fact that in Pro Tools the editing is nondestructive.

Session File Backups

Pro Tools has an Auto Backup preference (Preferences > Operation). If you turn this on, it will periodically save a backup version of the session file. These backup session files will be named “(session name).bak.00.ptf,… bak.01.ptf,… bak.02.ptf ” etc. and automatically saved in the Session File Backups folder.

You’re already a better Pro Tools operator

Now that you know how and where everything is being saved and stored for each session, you’re ahead of the curve.

Now you can keep track of your files and can back up, import or copy sessions without costly mistakes.

What Next?

I suggest taking the time now to go and create a new session. Go back and forth between Pro Tools and the Session folder on your hard drive so you can see it update in real-time as you add fades, region groups, and all the different file types you’ve learned about in this article.

Then get back to the music!