There's a home audio revolution taking place, and it's something you need to take notice of if you want people to hear your mixes at their best.

Download and listen to the audio files below.

If you were listening in stereo, then you should hear some phase related things going on to the acoustic guitar in example one and the synth in example two.

A New Generation Of Speakers

If you were listening on one of the millions of speakers such as the Sonos, Apple Homepod or one of the Amazon devices and using a single unit rather than a stereo pair, then your experience might be a little different. In some cases, both channels are summed, and when that happens, it can change the sound entirely.

If you want to know how the audio examples are likely to translate then play them back summed to mono... those who know their audio onions should be able to guess what happens, but for some, it's going to be a surprise.

We've tested this on our Sonos speakers and the result is the same as hitting the mono button on a mix. We would be interested in hearing from people testing this on other brands.

Why should this matter? Well according to a 2017 report from Strategy Analytics;

"Wi-Fi-based wireless speakers grew by 62% in 2016 to 14 million units with Amazon accounting for 77% of the increase in volume demand from the previous year. The company estimates that Amazon shipped over 5 million Echo speakers in 2016 compared to just over 4 million from second-placed Sonos…”Sonos has long been synonymous with connected home audio, and as recently as 2014 it accounted for 50% of the small but growing Wi-Fi speaker market…"

According to 9to5Mac "Strategy Analytics adds that it expects “Intelligent Home Speakers” to make up around 90% of all Wi-Fi speakers by 2022."

Of course, not all these speakers are the 'intelligent' type, but with or without a virtual assistant, single wireless speaker sales are growing fast, and that means a lot of people are not listening to music in true stereo. For the last 40 years music systems, as opposed to radios and TVs, have been overwhelmingly sold as stereo packages. Smart loudspeakers are being presented as standalone music systems with an option to add a second speaker (at double the cost), we shouldn't be surprised that so many people don't buy a pair.

We hope things will improve, Sonos allow users to pair two speakers to create stereo, Apple are reported to be planning the same with their Homepod, but many people are still listening on one speaker per room.

Any mix or mastering engineer worth their salt knows there's a vital part to checking any mix and that is running a mono compatibility check. Running a mono compatibility check on both audio examples shows you that some audio is not going to translate.

So whilst there's been a lot of industry buzz about the growth in multi-channel and immersive audio experiences it seems our attention to mono is more important than ever.

Now our audio examples are created to show you what happens when you start messing with the phase in extreme ways, but many mixers use widening both time and phase based effects to make certain elements super-wide like vocals, guitars and synths. If these mixes are not checked for mono compatibility, then your mixes could sound bad or disappear entirely on the latest audio equipment.

Checking Mono Compatibility

Some DAWs have a mono switch on the master buss; this is still lacking on some other DAWs. Without the option to check mono compatibility you are missing a vital part of the mix checking process.

Rest assured you can fix this in an instance.

Studio One

Studio One users it's as simple as hitting the mono button on the master buss. See the image below.

Pro Tools Workaround

Pro Tools users watch this video showing How To Create A Mono Button On The Pro Tools Master Fader

Logic Pro X Workaround

Logic Pro X users read this article How to Test Your Mixes For Mono Compatibility by Routing to an Aux Track Before the Stereo Output - Expert Tip by Logic Pro Expert Eli Krantzberg

Use A Free Plugin To Check Mono Compatibility 

We have an extensive list of free plugins for Pro Tools and free AU and VST plug-ins too, one of them is the Brainworx bx_solo. 

Brainworx created bx_solo to introduce users to the M/S technique for recording, mixing, or mastering. Key features of Brainworx´s famous M/S & Mastering products are included, like their unique Solo Buttons, which allow you to individually listen to all components of a stereo mix or stereo signal. 

Comprehensive solo features include; L (Left channel), R (Right channel), M (Mono sum, mid signal) and S (Stereo-Difference, side signal). This gives users the ability to listen to each component of a stereo mix when working in M/S modes, something modern DAWs often make difficult. bx_solo is also a powerful tool for checking your tracks or mixes for errors, noises, clicks and other problems.

Summary

Some would have thought that mono was dead, far from it, and now it is more important then ever to make sure your mixes work in mono.