This article explains how to connect your interface to a subwoofer and a pair of monitor speakers to listen to or mix stereo audio.
The user guides for some of our larger interfaces describe how to set up in 2.1, 5.1 and 7.1 for using multichannel audio, but it is more common to mix in stereo with a subwoofer.
To use a professional, active, subwoofer with stereo audio, you should not connect it to a separate line output on your interface. To set up a professional subwoofer:
- Connect the left and right outputs you usually connect to your pair of speakers, directly to the subwoofer's left and right inputs.
- Connect the left and right subwoofer outputs to your left and right monitor speakers.
The subwoofer's amplifier receives the full frequency range audio from your interface, and you can use the crossover dial/switch to control the frequency that is sent from the subwoofer to the monitor speakers. For example, if the crossover is set to 80Hz, you can expect the subwoofer to output frequencies below 80Hz and the monitor speakers to output anything above 80Hz.
Here is a diagram for setting up a common commercially available powered subwoofer:
In this example, we've shown a Scarlett 2i2 3rd connected to an Adam Audio T10S and connected to a pair of Adam Audio A series monitor speakers.
If you are using multichannel audio where the audio being sent to the Sub or LFE is not already at full frequency range, you will use the setup described in your device's Manual.
If you have a passive subwoofer/speakers, you would generally also be using an amplifier or home receiver to provide power to the speakers, so the stereo line outputs would go to the amplifier/receiver's L/R inputs. The amplifier/receiver would then act as the crossover/amplifier to the sub/speakers, splitting the audio properly.