Yesterday I went through the first four track types in Pro Tools – audio, MIDI, instrument, and aux tracks. Today I want to delve into the mysterious master track, or master fader track.


In a typical Pro Tools session, you’ve got a bunch of audio tracks, a few instrument/MIDI tracks, and a couple aux tracks. The outputs of all these tracks are typically set to “Analog 1-2,” the main stereo outputs of your interface.

Internally, Pro Tools takes all these individual audio signals and combines them into a single pair of outputs. This is called summing.

When all of these tracks are combined, it’s very easy to clip the mix bus. None of the tracks have to even be close to setting off the clip light, but when they’re all summed together, there’s a good chance that clipping is happening underneath the hood.

How do we monitor this? The answer is the master fader.

Master faders are really very simple. They allow you to monitor the volume level of any given bus or output in your system. You’ll notice that while audio and aux tracks allow you to select an input and output per track, the master fader only allows you to select either a bus or an output.

Once selected, the meter on the master fader will represent the combined signal of whatever bus or output you’re monitoring. Now, whenever you see the red clip light go off on your master fader, you know to bring the volume of the other tracks down.

Bus Processing

Master faders still have inserts. This allows you to process your entire mix through one series of plugins.

This is a common place to use compression and limiting to bring up the overall volume of the mix without clipping. This is what most people use the master fader for. It allows you to check your levels and process your master mix.

But is there more? Why even use a master track? Couldn’t an aux track do the same thing?

Unique Features of the Master Fader

The truth is that the master track has a few key differences from aux tracks. The Pro Tools manual goes into this in depth. (See the image below from the manual. It’s a diagram of the signal flow of the master fader.)

There are two features that make the master track unique.

Pro Tools Reference Guide, p. 848 © 2008 Digidesign

Pro Tools Reference Guide, p. 848 © 2008 Digidesign

1. No Input

You’ll notice that, as I mentioned earlier, there’s no “input” to a master track. The master track basically picks up the signal directly off of the outputs of all other tracks assigned to the same output. (“A 1-2” in the diagram, for example.)

While there’s no input to a master fader, there are also no sends. A master fader cannot be used to route signal. Think of it as the “last stop” for the audio. It’s the last thing to process the audio before it reaches its destination, whether that destination is an audio output or a bus.

2. Post-Fader Inserts

As I mentioned before, you can use plug-ins on a master fader. However, the master fader is unique.

Inserts on audio, instrument, and aux tracks are pre-fader. This means that the plug-ins process the audio before it passes through the volume fader.

Inserts on the master fader are post-fader. I’ll cover this more in-depth in the video below, but the main reason for having post-fader inserts (in my opinion) is for dither purposes. When you insert a dither plug-in on a master fader, you want the dither to stay at a constant volume.

Let’s say you were to do a fade-out at the end of a song by bringing down the master fader. If the inserts were pre-fader, the dither would be turned down along with the audio. This isn’t ideal.

On the flip-side, if you plan to do to a big fade at the end of the song, if you put a compressor on the master fader, it will be post-fader. This means that as the fader volume goes down, the amount of audio being sent to the compressor is attenuated as well. This will throw off the compressor, changing how much it compresses. This, in turn, will make your mix come “unglued” a bit as the track fades out.

Video Demonstration

The best way to explain this is to simply show it to you. In this video I briefly describe each track type, and I show you several different uses for master faders. At the end you’ll see an additional use for master faders that most people don’t do, but it may help you keep your mixes from clipping internally (without you even knowing it!).


See also:

30 Responses to “Video: Pro Tools Track Types Part 2 – The Master Fader”

  1. Lindsey Montana

    Hi Joe, I have to agree with “Name” that something seems to be wrong. At 3:59 in your master fader video, you mention that the master fader is “pre-fader.” Then, at about 5:15, you mention that lowering the master fader would have affected your compressor settings if you had used them on the master fader instead of the aux/submix. That implies the master fader inserts are “post-fader.”

  2. Hutchinson9736

    Great video, Joe!

    Do you know much about the Trim plug-in? For example, would it be better to use the Trim plug-in (& faders for volume adjustment) or just the faders or, like you are doing, faders + master to set the input level to the drum bus?  Or all three?! Forgive my ignorance.

    Thanks in advance… keep up the good work! 🙂

    • Joe Gilder

      The trim plug-in is helpful if you’re getting too much signal hitting one of your plug-ins. Perhaps the audio track is too loud and you need to turn it down so it hits the EQ or compressor plug-in at a more appropriate level, use the trim plug-in to lower that volume a bit.

  3. Cory

    Joe, can you send me a list of the articles your read that helped you discover the internal Master fader trick that you used in the video? Was one of them “Keep Your Headroom” by Mike Thornton from the Sound on Sound June 2010 issue? This is all new to me and is hurting my brain at the moment, so I need to wrap my head around other articles if you don’t mind sharing them. Thanks!

  4. james grant

    thnkz Joe the master fader use is very help full and cleared up a few thing’s about pre and post when using compression. what about EQ on the master,it should be fine no volumes to effect right?

  5. Ethan

    Hey Joe great video and article!

    I was just wondering…how do you route your tracks in order to send the individual tracks to the master and the sub mix? Like are your routing each track to the master then the master is routed to the sub mix for fx? Or do you have the tracks routed to the master and then the tracks routed to the sub mix? Thanks!

    • Joe Gilder

      You can’t “route” anything to a master fader. A master fader simply lets you monitor a particular bus or output.

      To answer your question, though. I route all the tracks through the submix Aux, then route that Aux to the main outputs.

      • Ethan

        Oh ok. So you just select whatever bus you want to monitor using the master fader you select?

        Ok great, thanks Joe!

  6. JG Music

    Hey Joe,

    I was wondering how you route your masterfaders. i mean you have 3 masters and one of them is your master out put, do you know what i mean ?.

    Thanx, Jeroen.

    • Joe Gilder

      You don't route anything to master faders. A master fader simply lets you
      see the meters and put effects on a particular buss or output.

  7. Tom

    Sure. In the Pro Tools 8.0 Reference Guide PDF, “Signal Flow by Track Type” starts on page 828. The diagrams show that inserts are pre-fader for audio tracks and post-fader for Master Fader Tracks.

    You can easily prove this to yourself by doing this:
    1) Create a session with one audio track (with an audio region to listen to on it) and one master fader.
    2) Insert a Compressor/Limiter Dyn 3 on the audio track and another one on the master fader. Display both plugins so that you can see them.
    3) Loop playback of your audio region.
    4) Pull the audio track's fader down while looking at its compressor. There is no change to the signal level hitting the compressor, because the insert is pre-fader. Put the fader back to unity.
    5) Pull the master fader down while looking at its compressor. You will notice the input level to the compressor (and therefore the gain reduction and output as well) going down because the insert is post-fader.

    The way Digi set this up is actually very useful, for reasons shown here
    about not being likely to clip the internal mix bus (it being 32 or 48 bits) and being able to scale down the number of bits you are sending to your D/A converter (which is most likely 24 bit, and easier to clip) with a master fader (not my site or info, btw).

  8. Name

    I hate to be the bearer of bad tidings, but you've got the pre- post- thing switched around. The inserts on a Master Fader are post-fader and the inserts on audio tracks are pre-fader. Check the Pro Tools reference guide again, or see the image you've posted above of the Master Fader track audio signal flow, which clearly shows that the inserts are post-fader. Sorry…

  9. Quincy Jones

    An incredible tutorial on the use of the master fader. To keep up with you in terms of you understanding of signal routing internal and external is going to take some time. Your session look organized which is a far cry from what I am to put together. By reviewing these videos though they may not make sense just yet I see the structure and I understand the concept. It will take time to reach this level but I am determined by any what ever means necessary. Good stuff ! Keep it coming… never apologize to your viewers for long videos. That’s why there the cue arrow for those who already understand. For us starters the more you can feed us the better. As far the last question asked: What do you recommend in terms of top notch tutorials … DVD… books… Lets us know.

  10. San Diego Band

    Hi there,

    Your video has clarify a bit what Pro Tools can do with, not only master faders, but also the rest of the tracks. My biggest concern, however, is that I don’t really know much about Pro Tools. I have been recording my guitars with the plugin (i.e. reverb), but you are saying that I should use a AUX track for that? Do I use the bus to route it to the AUX? This is still a bit confusing to me. ANy books or DVDs that are recommended? Any websites?Yours perhaps?



      • San Diego Band

        Hey Joe,

        I sound desperate here; sorry for that! It’s just that I have wasted so much time in the last few years, and now I decided to change my life (for good) and learn as much as possible about recording. I did get the AUX track setup down and it has helped me a lot. I continue watching all your videos and read all your posts… 🙂

        • Joe Gilder

          Thank you so much! I’m really glad you’re finding the blog to be helpful. Thanks for reading. Tell your friends!

          • Rony

            Hi Joe, great stuff with this video & website. I am learning my way thru mixing and need ur help here. Most of us just put our plug-ins on the tracks that has the particular instruments on it & really dont know how to put plugins on aux tracks & route multiple audio tracks to it. Could u help with a video here? Also, applying the necessary effects thru these two ways, what next? How does one complete the mixing process? I dont see a article that covers that…..

            • Joe Gilder

              Hi Rony! Glad to have you on the site.

              I think you’d be best helped by going through the other videos and articles I’ve posted here on the site:

              There’s a video on setting up aux tracks that should help you. Also, your question about “how does one complete the mixing process?” is pretty vague. Mixing involves a thousand different decisions, but most of my 600+ articles on this site cover mixing in some way.
              Have fun!


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