Using Multiple Audio Devices in Cubase on the Mac

I use Cubase on the Mac to create my music. One feature of this setup is that Cubase only allows you to use one audio device at a time. What if you have a nice audio interface and also want to use the USB interface on your Katana to record guitar? This article shows you how to do that. We use the Katana as an example but the principles shown here apply to any audio device.

I have been learning how best to get these working together effectively. The first challenge was being reminded that Cubase can only use one Audio device at a time, so I figured out how you can get around that using a feature that the Mac provides called an Aggregate Device. I’ll explain how it works later, but for now if you see that name show up in screen shots, just ignore it.

First of all I’d like to present the terrain we’ll be exploring. A lot of this is about audio interfaces, so we’ll be looking at the Mac’s Sound System Settings, the Audio MIDI Setup app, and inside Cubase, the Device Settings and Audio Settings screens.

If you have Cubase Pro, you’ll want to read the section Using the Control Room. It lets you get the most out of using multiple interfaces.

Before we get into the Katana, let’s get familiar with the basics, and see how the system looks when we have no external audio devices attached.

Using the Mac’s built-in devices

First, let’s look at the Sound page in the Mac’s System Settings. With no external audio devices or headphones connected to my Macbook Air M1, I see this:

Sound Systems Settings, no headphones.

I will explain the Aggregate Device later. For now, please note that you can go in there and change the volume, mute etc. Sometimes that’s where you figure out why you can’t hear sound – somehow the volume got lowered or the mute activated, or the device wasn’t selected.

When you hook up a new device, if it’s not visible here then it’s not going to work. If that’s the case see if you need to install a driver from the manufacturer.

Studio Setup with Default Devices

Now let’s look at Cubase. If you bring up the Studio Setup window using the menu item Studio/Studio Setup, you’ll see something like this:

Studio Setup, build-in audio

Note that in the left column, the Built-in Audio driver is selected. I clicked on the highlighted Control Panel button, and that brought up the panel to the right. You can click on Audio System to switch devices.

Take note of the ports. We have one input (the Mac’s microphone), and two outputs, mapped to the left and right speakers.

If you plug headphones into the physical headphone jack on the mac, you may have to go into the Control Panel from this screen, as shown below. there you can switch the output to the headphones.

Cubase Studio Setup dialog

If you have Cubase Pro, you can use the Control Panel to make both the speakers and headphones available, more on that in Using the Control Room.

Audio Connections

Next, go Studio/Audio Connections. Here you can make the audio device ports available to the mixer.

Go through the Input and Output tabs, a normal setup should look like this. You may have to click on and change certain things to make sure you at least have an output channel connected to a device, so that you can hear something. At this point I have these inputs and outputs:

The Mac’s microphone is connected to the “Microphone” input channel and will be avaliable as an input to any audio track you might create (though that won’t be of professional audio quality.) The main mix (The Stereo Out channels) will go out the speakers.

Using the Katana Directly

Now let’s plug in the Katana and see what we see. First, the System Settings/Sound page now looks like this (again, we’ll get to the Aggregate Device later):

Now let’s see how this looks in Cubase. First we’ll go Studio/Studio Setup to bring up this dialog:

The first thing to note is that the top item in the left panel, Audio Sytem, has KATANA3 selected. If it isn’t, then you can click on Audio System and select it. If the option isn’t there, you have other problems beyond the scope of this article.

Just plugging the Katana into your computer provides the Mac with 4 input and 4 output channels, stereo pre-effect and post-effect.

Let’s define pre-effect and post-effect. The Katana manual is freely available online, and it this handy block diagram:

Katana 50 Gen 3 block diagram

There you can see that the signal flows from left to right. At the very left is the guitar input jack. Next to that is where it is connected to USB ports 3 and 4, both for input and output.

If you want to hear the dry guitar sound without any processing at all, you can listen on ports 3 and 4 (left and right.) I always record that as a dry guitar track when I’m recording.

The inputs 3 and 4 are where you send a signal into the Katana to go through the effects. We call them the “Pre” ports. You use them to “re-amp” a track. The most common use case in this context, is to take a “dry” guitar track, i.e. one without effects recorded, and to send it out through an amp and then bring the signal back in to get recorded onto a new “wet” track. Often this means putting a microphone in front of an amp and recording that, but here we take the signal back out from the Post output ports 1 and 2.

The Post input ports 1 and 2 can be used to allow an external signal to be monitored through the Katana’s headphone jack. This is where we will be sending the mix from Cubase.

Naming Ports

Now that we know why we have 4 inputs and 4 outputs, we can give them descriptive names. If you refer to the Studio Setup screenshot above, you’ll see that there is a “Show As” column for each port. You can edit the names there. Mine now looks like this:

Next, we’ll go to Studio/Audio Connections. This is how I’ve got my inputs and outputs set up:

Now everything works, but you can only hear the Cubase mix from the headphone jack on the Katana.

The Solution: an Aggregate Device

The Macintosh has a nice feature called an Aggregate Device, which lets you combine audio devices together into one bigger device. Then when you use that device, say in Cubase, you have access to all the inputs and outputs of all those devices. This provides great flexibility in configuring audio.

First of all, let’s do something relatively simple, which is to combine the Katana with the Mac’s speakers and headphone outputs, so those are all available in Cubase.

You do that by bringing up the Audio MIDI Setup application, and select the Audio Devices window. Ensure that your Katana is turned on and plugged in, it should be visible in that window. Also, plug a pair of headphones into your Mac if you have them.

Click the big plus sign at the bottom left, and select Create Aggregate Device.

An Aggregate Device is a software device that can reference multiple physical devices, and make them all appear as different ports on one device. That’s how you can get software that can only connect to one device, e.g. Cubase, to connect to different devices.

This is what my aggregate device looks like right now. I didn’t include the microphone:

You can see that the Katana, the Mac’s speakers and headphones are now combined into one device. It has 4 inputs (the Katana’s Pre and Post stereo inputs) and 8 outputs (the Katana’s Pre and Post stereo outputs), as well as the Mac’s speakers and heaphones (2 more ports each.)

Now let’s go back into Cubase and see how to hook it up.

Here’s what my studio setup looks like, after renaming the ports:

Now we can go into the Audio Devices page and assign them. Here’s what I did. Remember the names we’ve given: “Post” and “Pre” for inputs, “Stereo Out” and “Reamp” for outputs.

Now let’s look at the mixer. Here we can see the input channels named Pre and Post on the left. Then we created two stereo audio channels to record a guitar.

Guit Pre is where we record the “dry”, unprocessed signal. Note that in the routing section, we’ve selected “Pre” as the input.

Guit Post is where we record the “wet” signal that has all the Katana’s effects and amp modelling. Here we selected “Post” as its input.

Once we have a recording, we can re-amp the dry signal through the Katana, choosing a different amp model and effects. We’ll record that on a new Audio channel we call “Guit Reamped.” We’ve changed the output of “Guit Pre” to “Reamp”, that’s how we send it out to the Katana.

Using the Control Room

If you have Cubase Pro, using the Control Room lets you get the most out of having multiple devices.

Open the Audio Connections panel from the Studio menu, and select Outputs. Disconnect the Stereo Out, as we’ll control output to the speakers from the Control Room. Even though it’s disconnected, it’s selected as the “Main Mix” which is how we can see it in the Control Room. You can see that if you right-click on Stereo Out.

Now go to the Control Room tab. Enable the Control Room using the button at the top left, and then assign the ports as follows. Note that we’ve added a “Cue” send called Foldback to send the mix to the Katana Post input, so that you can hear it if you’ve got headphones plugged into the Katana. The “Phones” output is for the headphones plugged into the Mac.

Audio Connections

Then let’s look at the Control Room:

Control Room, minimal configuration.

At the top, you’ll see the Cue channel we created to send a mix to the Katana’s post input. At the bottom, you’ll see we’ve got controls for the Phones and Main (speakers.) These get their signal from whichever output is selected as the “Main Mix” – see above.

Now if we look at the mixer, you’ll see that the Foldback output shows up in the Cue section. That let’s us control exactly the mix we want to send to the Katana’s headphones. If you just want to send the main mix, just select that one and turn the other ones off, as shown here:

Conclusion

This concludes our discussion of Cubase and aggregate audio devices. Aggregate devices allow you to work with multiple audio devices at once. The Control Room is great for switching between different monitoring devices, and configuring different cue mixes to send to the musician’s headphones. I hope you find this helpful!

If you have any questions or comments, email me at feedback@damaru.com. I’ll add useful questions and answers here.

Damaru Inc