VST/Audio Connections: Setting up an audio interface in Cubase/Nuendo

To be able to use an audio interface in Cubase/Nuendo, knowing how to hook up instruments and microphones and the computer is not enough. There are also some 'virtual cables' that need to be connected on the software side.

This Help Center article describes how to set up an audio interface in Cubase or Nuendo in three steps:

Before you begin, please make sure

you have installed the latest driver available on the website of the manufacturer of your audio interface. If you want to use the internal audio hardware (onboard sound chip) of your computer, check the website of the manufacturer of your computer resp. mainboard for driver updates.
you have installed the latest update available for your Cubase/Nuendo version.
your audio interface is connected to your computer and switched on, too...

Ready? Then start here:

1. Selecting the audio interface driver

In the first step, Cubase/Nuendo must be told which audio device to use, particularly if there are several options - for example, the internal audio hardware and an external audio interface connected via USB.

Select 'Studio Setup...' from the 'Studio' menu.
◷ Older Cubase/Nuendo versions: Select 'Device Setup...' from the 'Devices' menu.

The setup window opens.
In the 'Devices' column on the left, select 'Audio System'.
◷ Older Cubase/Nuendo versions: Select 'VST Audio System', 'VST Multitrack' or 'VST Audiobay'.
Select the driver of your audio interface from the 'ASIO Driver' pull down menu on the right.
If your audio interface is not listed, make sure the latest driver is properly installed - and that the device is correctly connected and switched on.

Click OK to close the setup window.

Cubase is now basically connected with the audio interface. Often, particularly if you are using a simple audio interface with two input and two output channels, recording and playback will already be possible. However, it is recommended to check whether the busses are correctly configured.

2. Configuring input and output busses

Input and output channels in Cubase are organized in busses. By default, an empty Cubase project ('Empty' template) has a stereo input and a stereo output bus, each combining two channels of the audio interface. If needed, busses holding more than two channels can be set up as well as single-channel (mono) busses.

Important: Only channels that are assigned to a bus are available for recording and playback in Cubase/Nuendo.

Select 'Audio Connections...' from the 'Studio' menu, or press F4 on your keyboard.
◷ Older Cubase/Nuendo versions: Select 'VST Connections' from the 'Devices' menu.

In the newly opened setup window, select the 'Inputs' tab (1).

By default, you'll find a single stereo bus named 'Stereo In' in the 'Bus Name' column on the left.
If you need more input channels (or if you want to access the two channels via two mono busses), you'll need to create an additional bus by clicking on the 'Add Bus' button. To remove a bus, right-click anywhere in its row and select 'Remove Bus ...' from the contextual menu.
Make sure your audio interface is listed in the 'Audio Device' column (2). If it appears to be not connected, click in the column to select it from the pop-up menu.
Make sure the input channels of your audio interface are assigned correctly in the 'Device Port' column (3).

Once you've set up the inputs, switch to the 'Outputs' tab and assign the output channels of your audio interface accordingly.

Read more on Audio Connections in the online operation manual: Cubase | Nuendo

3. Selecting the input and output of an audio track

Now that the audio interface has been selected and busses are configured, you can specify inputs and outputs of audio tracks in your project. There are several ways to do this. The track routing can be set in the MixConsole (at the top of each channel) and in the 'Channel Settings' window.

In the following instructions, we will use the Track Inspector, the vertical parameter bar left to the Track List. In case the Track Inspector seems to be missing, set the Left Zone to be shown via the 'Setup Window Layout' option in the Toolbar at the upper right (◷ older Cubase/Nuendo versions: upper left) or press alt + I on your keyboard.

Select an audio track to make its attributes accessible in the Track Inspector (1).
Click on the Inspector tab at the top (2). It's the one showing the track's name.
The related settings fold out.

Make sure the correct bus is shown in the 'Input Routing' field (3). If not, click on the field to select from the list of available input busses.
Note: On a stereo track, selecting a stereo input bus is sufficient. However, on a mono track you'll need to select one of the input channels of the stereo input bus instead. In case you have a stereo audio interface, this usually means choosing between left or right channel. Alternatively, you can set up mono input busses which can be selected directly on a mono track.

The audio interface set up is now complete. Cubase/Nuendo is ready to record and play back signals via the selected audio interface.