Mixing in Mono
Mixing in mono is the single most ruthless way to expose inadequacies in your mix. The mono mix is more than just a tool for finding phase cancellation issues in your game audio.
Some audio engineers just do a quick mono check to ensure their stereo mix collapses down for mono compatibility. This is primarily to ensure everything can be heard when played back on low-end, mono consumer speakers. They do this by switching output to a single speaker. For those of us with a standard DAW setup, we are have to do some work to truly mix in mono. Luckily, there is a way to use your stereo headphone out and convert it to mono via a mono cable.
Routing a mono signal to a single speaker is the goal here. You've probably seen multi-million dollar studios with that tiny box in the middle. Going mono allows the engineer to dial in the mids, which is where most of the musically useful information lives. If a mix has a muddy midrange, then this will most certainly expose it.
Aside from all the technical reasons to do this, there is just something simple and fulfilling about having to only deal with one speaker. Give your ears a break and start mixing at low levels for a change.
Most of us have been so busy basking in the wonders of stereo and 7.1 surround, that we forgot the simplicity of monophonic music. Even the Beatles albums have been reissued in their original, monaural form, much to the delight of music purists.
The legendary Auratone speaker is the original choice for mono mixing. There are a few knock-offs out there, but none compare to the real thing. Auratone is a 50 yr old family owned company that only makes one product.
For years, such speakers were referred to as "horrortones" due to their 90Hz to 17kHz frequency range. If you can make it sound good on these, it will sound good everywhere. When an entire mix is crammed into a single, non-ported speaker like this, it throws a floodlight on the midrange and you begin to hear all your game audio tracks fighting for attention.
For those with a single stereo headphone output, a special, mono summing cable must be made from scratch using soldering equipment. These cannot be purchased anywhere! While this is a welcome challenge for the DIY crowd, the rest of us wonder why such a cable has never been commercially available. Here is a tutorial on rolling your very own mono cable for use in game audio and beyond.
May the Mono be with you! This mono mix technique is a great way to improve your mixes and compete with the top audio studios worldwide.