How do I Mix in Mono?

The way you mix and mono will depend on your setup.

For example, my home studio is equipped with the Universal Audio Apollo audio interface, which has a built-in mono button. Regardless of what DAW or program I’m listening to, the hardware will put my mix into mono.

However, if you don’t have an interface with a mono button, you have to resort to a DAW. For example, if you want to go to mono in Pro Tools, you can hold down the “alt” key and press the master fader pan knobs.

Each DAW has a different method of stacking mixes in mono, so be sure to check your user manual. Once you figure out how to stack your mix in mono, you can start working on it.

Balancing the levels of your mix in mono

Long before processing plug-ins were invented, and even before hardware equalizers and compressors were integrated into music studios, mix engineers were “balance” engineers. Their main goal was to make sure that every element in the track was heard, and that the most important elements were heard better than the least important. To this day, volume balancing remains the most important factor in a good mix, but many young mix engineers overlook it.

There are many different ways to achieve good volume balance.
For example, some engineers like to arrange volumes in order of importance.
With this method, you switch all faders down and start by raising the fader of the most important instrument. The most important instrument depends on the track, but in many cases it is the vocals. The idea here is that you bring the vocal to a good place, leaving a lot of headspace on the master bus, and slowly raise the other instruments around it in order of importance until each element is clear and defined.

Although this technique works for some people, it never worked for me

I have become a big fan of what I call the “bottom up” technique.

To get the volume balance, I will start with basic instruments such as drums and bass. I will continue my way up, balancing rhythm guitars, keyboards, synths and effects, knowing that at the end I leave room for the main elements (leads and vocals).

If you’re crazy like some engineers, you can turn all the faders on at once and slowly adjust until you find the right balance between all the elements.

The way you do this is up to you, although the ultimate goal is to make sure that each element has its own space and a clearly defined role in the mix.

EQing your mix in mono

Monophonic fun isn’t limited to volume balance! I often like to do EQ and compression while I’m at it. When listening in stereo, it can often be hard to tell if two instruments are competing with each other or not, especially when listening to low-pitched instruments such as drums and bass. Similarly, it can be difficult to determine whether midrange instruments such as guitar, keyboards or vocals are absorbing low-frequency instruments because they themselves have too many low frequencies.

With monophonic mixing, we can adjust the EQ across the entire frequency spectrum to avoid fighting for space. Many engineers use panning to compensate for EQ masking, but this is just a band-aid for problems that become apparent when listening on monophonic systems. You can even listen to dynamic problems when mixing in monaural.

For example, when listening in stereo, the background vocals may seem quite balanced. However, when mixing tomes, you will notice several dynamic inconsistencies in the background vocals, causing them to overshadow the lead. To make the dynamics more consistent, you can use compression.

When should you switch to stereo?

There’s no reason why you can’t do about 80-90% of your mix in mono. It can end up being quite useful. As I said before, my philosophy is that if you can get your mix to sound great in mono, it will sound absolutely incredible when you listen to it in stereo. That said, at some point it’s important to recognize that stereo systems are just as common as mono systems. From headphones to cars to large concert venues, having width can add a whole new level of excitement to your mix for different audiences.

So, when should I go back to stereo in the mixing process?

The most obvious answer is when you do any stereo processing, including adding stereo reverb, stereo delay, stereo amplification, etc.

You’ll want to see how your stereo processing solutions will respond to stereo systems in the real world, and it’s impossible to listen truthfully when mixing in mono.

Use Mono to check for phase disturbances

One of the most common culprits of phase problems is sounds scattered across the stereo spectrum. Mixing engineers make certain processing decisions with panning, EQ or effects that sound great in stereo, but when mixed in mono they find that they destroy certain parts of the mix.

Phase problems can not only give a weird, hollow and metallic character to the timbre of your instruments, but also make certain parts of your mix disappear completely. This often happens with paired vocals that are scattered all over the stereo field.

When you mix in mono, you get a hollow, chorus-like tone that sounds unnatural. Avoiding this is very easy by making the right EQ choice to separate the two sounds when mixing in mono.

The main point here, however, is to constantly check for mono compatibility in your mix. Whenever you take a stereo solution, press the mono switch and listen to see if anything sounds weird or unnatural.
Always double check your stereo decisions

When you’re nearing the end of your mono mix, be sure to double check all of your stereo mix solutions to see how they sound.
For example, you may have made some volume adjustments early on that now feel like they need a little adjustment when panning.

Not only are you balancing your mix by making compromises for every element in it, but you’re also making compromises in your mono and stereo mixing decisions so that the whole track sounds equally good in both cases.

Do you need to use plug-ins to extend stereo

With so much talk about mono compatibility, many engineers worry about using stereo width plug-ins, which are some of the most notorious culprits of phase problems. Few things in life sound as good as a soft Rhodes keyboard laid out on the sides of your speakers with a chorus plug-in.

But will it destroy your mix?

I can’t give you a definite answer, although I can advise you to check in mono if you decide to use this type of processing. In some cases it won’t have any negative effect, and in others it can cause a huge amount of phase problems. However, if there are phase problems, that doesn’t mean you should back out of your creative solution. You might think, “I’d rather have that gorgeous, ultra-wide Rhodes keyboard in my mix than have to worry about whether people listening to mono can hear it as clearly.”

That’s perfectly fine!

Compatibility with Mono is not a cause for fear. It’s just something to consider. However, there are some stereo extension plug-ins that are better compatible with mono than others. One of my favorites is the iZotope Imager, which is a simple tool for extending mono signals over the stereo field or narrowing down wide stereo tracks.

Final thoughts – incorporating mixing in mono into your music production process

Working on your mix in mono is a great way to make sure your stereo mix will make sense to listeners in the real world. Try mono mixing yourself and see what you think! Remember, though, that you want to mix your track the way YOU want it to sound. Even if you don’t want to do the whole mix in mono, check it often in mono to see if you hear phase issues or if your EQ balance is good.

If you’re mixing a song with tons of stereo sound that you want people to listen to on headphones, make the mix with that in mind. On the other hand, if you’re mixing a track that you plan to hear in a club, your mono mix is crucial.

Ultimately, listening to your mix in mono is a great way to get a clean sound out of your mix. Without the distraction of a stereo image, you can better balance your mix and thoroughly analyze the different frequency ranges.

Mixing in mono can save you a lot of time and headaches.