MONO VS. STEREO: WHEN TO USE EACH TRACK TYPE
When you add a new track to your DAW session, you’ll have to decide between mono vs. stereo. But what does that actually mean? When should you use a mono track and when is stereo the better choice? In this article we’ll explain everything you need to know about mono vs. stereo—from tracking to the final master.
What is mono?
Mono is single channel audio that offers no information about where a sound is, relative to the listener.
A mono track reaches both your ears without any difference in what you hear in the left or right side. That means that mono has a flat, direct sound without any sense of direction. Mono was the original format for recorded music because many early playback systems had only a single speaker. That’s why so many classic songs from the early pop era were first mixed in mono. Mono only recordings are rare today, but mono tracks still have an important place in music production.
What is stereo?
Stereo is a two channel audio format that delivers different audio information on the left and right sides. Stereo audio mimics how you hear sound in the real world with your two ears. Differences in timing, level and timbre give your brain subconscious clues about where a sound is located around you.
In music production, your final master will always be a stereo file. Choosing the positioning of your sounds with panning is one of the most important jobs in mixing. When should I use mono tracks, and when do I use stereo tracks?
Mono tracks should make up the bulk of the channels in your mix. Unless your source has a natural spread of stereo information, recording in mono is your best bet. You might think that too many mono channels would make your mix sound narrow, but remember that mono tracks can be panned to any location in the stereo field using your DAW’s mixer.
The easiest way to get a wide sounding mix is to spread your mono tracks out in the texture. That means placing some elements far out on the extreme left and right sides of the stereo field, while keeping others close to the center.
When should you use stereo tracks?
You should use stereo tracks whenever you record something with natural spatial qualities that you want to reproduce in your mix. For example:
Stereo mic’ed drum overheads
Sounds with reverb or stereo delays
Synthesizers with stereo outputs
Drum computers with stereo outputs
All these stereo source types include some information that’s the same between channels and some that’s different. If a sound has the same intensity in both the left and right channels, you’ll hear it panned dead center in the stereo field. If the sounds are different in level, timbre or timing between the left and right channels, you’ll hear them in position within the stereo track. Most stereo tracks include a mix of mono and stereo information. In fact, it’s unlikely that any stereo tracks will be 100% different between the left and right channels.
Mixing in mono
Even if massive width is your goal, mono still has a place in your mixing workflow. With so many different elements in a dense mix, it can be difficult to identify the most serious conflicts. Adding pan position to the list of variables only makes your job harder. That’s why many engineers use mixing in mono as part of their process. By temporarily flattening all the stereo information, you’ll get a clearer picture of how each sound in your mix interacts with the others.
To learn more about how mixing in mono can benefit you, head over to this in-depth guide.
To test your mix in mono, all you have to do is use the mono sum option on your master fader, monitor controller or interface to hear how it sounds.
Mono compatibility
Hearing your mix this way is important for more than just the mono mixing technique. In fact, you should test your mix in mono even if you only ever mix with both channels active.
The reason? Compatibility.
Mono compatibility means how well your mix performs when it gets summed to mono. Summing to mono is when the left and right channels add together to create a mono signal. If there’s conflicting information between the two channels, some sounds may cancel each other out. You might wonder when this problem would ever happen since most playback systems have two stereo speakers.
The truth is that plenty of stereo listening systems are more mono than they seem. Club systems, large installations, but also phones, Bluetooth speakers, laptops and most other small speaker systems are often summed to mono.
Make sure to check your mix at least once for mono compatibility before sending it off for mastering.
The main root causes of poor mono compatibility are:
Too many stereo tracks
Artificial stereo widening plugins
Too much reverb or delay
Phase issues between microphones
