Listening to your music in mono is a great trick which will help you clear out phase issues and get a feel of how your music will sound through a single speaker. It can also show you where elements of the mix stand, and correct potential problems that may arise. In this tutorial, I will show you how to add a mono channel to your output bus, so that you can listen to your mix in mono.
The Output Bus setting is where we can add a mono output bus for your mix. Go to the Devices menu and select VST connections, or alternatively press the shortcut F4. Here you will be presented with tabs related to Inputs, Outputs, Groups/FX, External FX, and External Instruments.
Select the Output tab and click on the Add Bus button. You will be presented with a dialog box where you can enter the number of buses that you need, and their configuration. To add a mono bus output, select the Mono option from the drop-down list. The mono bus will be added in the list of outputs that are available.
You can also rename the outputs by double-clicking on the name and entering a new one.
Next, select the Audio Device that you are using, and then select the Device Port that you will be using. This is important because this is where all the output from your mixes will be routed. So make sure that you select the right output port.
Once you're done setting up the Output Bus, you need to change the outputs of the tracks to the Mono Out bus that you just created. Select all the channels that you need to change (by Shift- or Ctrl-clicking), then go to the Output Routing of the selected channels from the Inspector, and press Shift+Alt and click on the Mono Out bus.
You can also set the Mono Out channel to be used as a main bus by selecting the Use Mono Out As Main Mix option in the right-click context menu. This will make all the tracks that are created to be routed as to have the Mono Out Bus as the default output channel.
Now you will be able to hear the output of the channels that you modified through the mono speaker.
With this trick up your sleeve, you can easily troubleshoot your mixing problems. You can discover phase issues in your mix and fix them. Even when you are mastering a song, it’s always a good idea to listen to the song in mono, because you will know how it will sound through a single speaker (e.g. a mobile phone speaker), and tweak the settings to make it sound better.
Almost all television networks listen to the music in mono so that phase issues can be solved. So next time you submit a song to a television network, make sure that you listen in mono and solve all the problems that you might find.