Intro
Quite a lot of times I ran into the discussion when two assistant engineers argue about the fact that there’s no (physical button) freeze function within Pro Tools, meanwhile there is for native sequencers such as Cubase, Logic, and so on. Let me first off correct every one with the common mistake of comparing Pro Tools which is a high definition audio recorder, with MIDI sequencers such as Cubase, Logic and so on; and the answer has already been given ;-). I won’t dig deeper into the entire structure of the differences software programming wise.
Now we have that clear lets dig a little into the history of the process of recording audio and its audio recording devices.
Back in the day when we were in the pre- pro tools days everything got recorded to tape. Which, again, came in different types, sorts, and brands. Best known examples are the ½”, ¾”, 1” and 2” tapes and 2, 4, 8, 12, 16, 24, 32 and 48 track machines.
Whenever mix engineers are satisfied with their final mix, they will go ahead and proceed to print the mix. Usually in different versions like ‘Main Mix’, ‘Instrumental’, ‘T.V. Version’, and ‘a Capella’. Not such a big problem if you don’t print any stems or single instruments, but what did the recording engineers do? They needed to record every single instrument to a different track. As you can imagine running a tape machine with only 4 tracks or 8 would be a big challenge as recording engineer. Despite the fact that you could sync several machines together in a chain, it would still not really give you a solution. Legendary Beatles producer George Martin used a bouncing technique which we can identify now as the early beginnings of the famous ‘freeze’ function in our MIDI sequencers.
Bouncing
Let me give you more information about this ‘bounce’ technique which will clarify its parallel in todays working with Pro Tools as audio sequencer (recorder). At any given point in the recording process, any number of existing tracks can be “bounced” into one or two available tracks and then erasing the original tracks, making more room for more tracks to be reused for fresh recording, or in computer recording to free up more ‘voices’ and processing power (CPU or TDM).
You can see Pro Tools HD as a multi track recorder and its sample rate as the type of machine.
48kHz – 192 Track/ Voice Count
96kHz – 96 Track/ Voice Count
192kHz – 36 Track/ Voice Count
*Note: Set DAE buffer size to 4 for 192 tracks@48kHz sample rate.
Running at 48kHz, you’ll have a 192 Multi Track Recorder, running at 96kHz you’ll have a 96 Multi Track Recorder, and on 192kHz you’ll have a 24 Track machine. But keep in mind that Aux Input Tracks do not eat up any voice(s)!!!
Personally I run all my sessions with a bit rate of 24 @ 96kHz.
Tape Bounce vs. Track Bounce in Pro Tools
To get back to the point of my blog post; freezing tracks in Pro Tools.
Instead of having a physical button for freezing tracks, you record these in a similar way as the analogue tape days to a new audio track and making the ‘bounced’ tracks ‘inactive’ as if you erased them on the tape machine, freeing up additional voices and processing power (CPU or TDM). The advantage of doing this in Pro Tools nowadays than on tape, is that it is not destructive as it was back in the day. By erasing your bounced tracks you lost them forever. By making those bounced tracks inactive in Pro Tools you can always go back in time and make adjustments to those individual tracks. Instant recall at a glance of your finger tips!!!
On top of that puts bouncing tracks less load on your system than if you’d ‘Bounce To Disk’ for instance. Also the Pro Tools mixer works in 48 bit, bouncing this data to disk would occur in the problem that Pro Tools needs to truncate to 24 bit or even worse (when working) in 16 bit (!!!). Therefore your mix will sound slightly different and a bit rough around the edges when using the ‘Bounce To Disk’ function within Pro Tools. You won’t have this problem when ‘freezing’ tracks.
Another advantage over ‘Bounce To Disk’ is that you can record all your stems at once instead of doing this stem by stem.
Setting Up Track Freezing
Instead of routing your stereo mixdown to the outputs 1 – 2 you route them to separate busses (Any available). For example; the aux input track picks up busses 1 – 2, and its outputs is routed to busses 3 – 4. I Solo Safe these Aux Input tracks by holding command+click (MAC) or windows+click (PC). A new audio track is created afterwards and put in Record Mode and picks up busses 3 – 4 and records the audio signal coming from its input. I do activate the ‘I’ (Input Only) button next to the ‘R’ (Record) button so I can hear the entire mix. That’s it!
*Note for Pro Tools LE users: You need to put the ‘bounce’ track in Record Ready, and Input Only monitoring should be selected.
Exporting The Stems
Now we know that ‘Bounce To Disk’ truncates all mixer data, how can we export our stems or even our final mixdown?
Select in Pro Tools in the ‘Edit Window’ the audio regions you wish to export (I hope you bounced entire tracks and not sections, if not please consolidate your audio tracks: Option+Shift+3) and click on the right hand menu in Pro Tools named ‘Regions’ (if this doesn’t appear, click below in your window on the right hand side in Pro Tools on the <
Nine out of ten times I can adjust the audio into what the client wants to have changed simply by sub –or additive equalization. For example quite a lot of times clients want to change the overall Snare Drum in the mix cause it’s either overpowering the mix or exactly the opposite. By simply pulling down a little around 4,000 cycles on the EQ on my Drums Stem I achieve a less overpowering Snare Drum, or in the other case boosting a little around 4,000 cycles will bring the overall Snare Drum sound up a bit more in the mix.
This is more time efficient, and way easier than going back in the mix completely via recall sheets and so on. On top of that will my session be extremely organized with all the instrument tracks, dupes and mults inactive, with only the stems active.
You can see that I absolutely never use ‘Bounce To Disk’ anymore.
Signing off,
The Music Surgeon mixer par excellence.
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