If you have a number of audio interfaces on your Mac then you might find yourself either switching between them for Pro Tools sessions, or even wondering if you can use the power of all of them at the same time.
Using the Aggregate Device option in the Audio MIDI setup window on your Mac you can create flexible input and output setups for any audio application on your Mac.
Also, re-checking (and sometimes reordering) the devices in the aggregate is sometimes necessary depending on your computer and usb hub situation. This can happen if you use a laptop and unplug/plugin different devices (eg you plug-in to a dock or add a usb device or hub). If your setup is relatively static, you may not see this issue.
Create An Aggregate Device In Audio MIDI Setup
To create a new Aggregate Device on the Mac simply open the Audio MIDI Setup application and then use the drop down menu in the bottom left of the window. Choose ‘Create Aggregate Device.’
You will then be presented with a list of all available audio interfaces. Simply tick the ones you want to use, in this example we are using an Apollo Twin connected to a 4-71-D via ADAT and a PreSonus StudioLive 16.0.2.
One thing you need to make sure is that of is that one interface is the master clock source and that all other audio interfaces in the aggregated set-up are running at the same clock speed. Once create our set-up looks like the image shown below.
click to enlarge
As you can see we now have a possible 36 inputs and 28 outputs available to us. Remember when using Pro Tools a maximum of 32 inputs is available, this will not be the case on other DAWs.
Setting Up The I/O In Pro Tools
To make sure Pro Tools can ‘see’ all the available I/O you need to go to the ‘Setup’ menu and select ‘I/O’ You’ll see the image shown below.
Click to enlarge
The fastest way to get all the I/O set-up is to delete all the inputs then click default and repeat this process in both output and bus tabs too. You should now have all the I/O available to you.
Selecting The Inputs And Output In Pro Tools
Now when you create new tracks in Pro Tools you will have all the inputs and outputs available for use. See below.
Pro Tools Inputs
Summary
This is a cool way of handling multiple interfaces without going through the pain of relaunching Pro Tools or for getting lots of I/O from a number of interfaces. One such scenario may be wanting to track a guitar via the Apollo with effects but using an Apogee Ensemble as you main interface. Or tracking guitars via Eleven Rack and whilst using an Apollo as you main interface.
In some cases the Mac will let you mix the protocol, so in this scenario we’ve got a Thunderbolt and a FireWire interface running as an aggregate device. Unfortunately you can’t do this with Pro Tools | HD interfaces.
Need more inputs or outputs than your current audio interface provides? Got 2 interfaces? Running Mac OS X? Hollin Jones explains how Audio MIDI Setup can fool your DAW into using two devices as one!
Anyone who has been making music with Macs for more than a decade will remember the “bad old days” of OS9, when audio and MIDI streaming in and out of a computer meant relying on specially written drivers and the OMS MIDI system. These were bolt-ons, and together with OS9’s inherent stability problems related to Extensions (I still shudder when I think of how often Macs used to crash compared to today), meant you were more or less at the mercy of whoever had written the drivers for your device.
This all changed with OS X, which uses CoreAudio and CoreMIDI frameworks built in at system level. Developers are able to use these standards when making hardware and software, and the result is an infinitely more reliable way to transfer data. Some time ago, OS X gained a rather interesting ability which addressed a fairly common problem for musicians. This is the ability to aggregate multiple audio interfaces or hardware connections into a single virtual device. So if you have two audio interfaces, one with two inputs and one with four, you can connect them both, perform a quick setup and they will appear to your DAW as a six input device. It scales up too, so you can add as many devices as you can physically connect. Since DAWs can normally only see one interface at a time, aggregating several devices “fools” them into seeing several devices at the same time. Here’s how it works.
Step 1
Open the Audio MIDI Setup application on your Mac and go to the Audio Devices window. Click on the plus icon at the bottom left of the window to create a new Aggregate Device, then double click in its name field and assign it a name.
Step 2
In this example you’ll see that I have two external devices connected as well as my MacBook Pro’s built-in audio hardware and a Soundflower virtual routing device. For simplicity’s sake, what I will do is assign the two hardware interfaces to work as one. So I click the Use boxes for the Xiosynth and the Yamaha device.
Step 3
You’ll notice that my Aggregate device is now reporting 14 ins and outs, which is the sum of the 2/2 of the Xiosynth and the 12/12 of the Yamaha. I have set the larger Yamaha device as my Clock source, and gone into the Xiosynth’s tab to make sure that it is working at the same sample rate as the Yamaha.
Step 4
Next I open the audio preferences in my DAW, which here happens to be Logic, and set the input and output to the Aggregate device.
Step 5
Now when I create an audio track, I can set its input and output to use any of the 14 channels available, either when creating the track or from the channel inspector. These correspond to the twelve channels on the Yamaha plus the two on the Xiosynth.
Step 6
Here is the same thing set up in Reason and you will notice again that there are 14 ins and outs available. If you needed even more you could add more devices or even use the built-in audio hardware on your Mac, though it won’t offer the same recording quality as a dedicted unit.