Mid Side Monitoring
A Secret Weapon To Great Masters

Want to avoid nasty mixing surprises?

Want to keep your M.E. happy?

Then follow these mid side monitoring guidelines while mixing your tracks!

Why bother?

• Instant check for mono compatibility
• Quickly determine, deal with, and eliminate phase issues
• Achieve a better, solid stereo image
• Better frequency balance and distribution
• If you’re converting to an mp3, it lets you hear any artifacts being created and tip you off instantly if you need to use an alternate bit rate/conversion scheme to minimize said artifacts
• You’ll know you’ll still sound good on FM radio when your listener’s car is out of range for stereo reception
• If it kicks in mono, it’s 99.9% certain it’ll kick in stereo and that means better transferability on different playback systems!

Ultimately, with mid side monitoring as one of your tools, you’ll sound good, everywhere - OK?!

Before explaining what to listen for, we’ll re-visit the nitty gritty of Mid Side techniques to explain what we’re listening to.

What are we hearing - what’s actually happening?:

To review, we’ve covered the basic starting set-up here.

When preparing a stereo file for mid side work, first we sum the left and right channels to give us the MID signal.

For the SIDE signal we invert the polarity of one the channels, and then, sum to these two channels together. Here now, any element of the signal that appears in both the left and right channel at equal volumes vanishes.

That’s as far as we need to go for this discussion here.

How to do it?

To automate all this for you, I offer these two methods; both very simple - and 100% effective.

They are:

• TC Electronic’s Audio Interface: Twin Impact
• BrainworX free plugin

TC’s option (the one I currently use) can be accessed by toggling on the front panel or through its software mixer.

But, if your happy with the audio interface you have, BrainworX’ free plugin allows you the very same options simply by inserting it at the end of your master buss. (This also allows single left and right channel monitoring, among other things).

Now we know what we’re doing, how to do it, and why, let’s find out......

What to listen for in mid side monitoring:

1. The mid/mono signal should be the loudest in all frequency ranges compared to the side signal
2. The side signal should ideally have no content below around 100 Hz - in other words no bass
3. The side signal should have no frequency portion sound louder than anything in the mid signal - at most it can match the mid but should not exceed it

First Point:

You’d better have all the drama, punch, and power happening in the mid signal that you have in the full stereo signal.

This goes back to the why:

• The mid is all what your car listener will hear when driving out of range of the FM transmitter.
• The mid is all what students will hear when college radio stations pipe their broadcasts through the college hallways - hey there’s no stereo there, just mono!
• The mid is all what gets heard over most club systems...

You get the point - I hope!

Second Point:

This avoids playback problems on challenged systems like boom boxes - problems like unwanted vibrations and resonances.

This is also important if you plan on cutting your track to vinyl. You don’t want your listener’s needle jumping out the groove because you spread your bass too wide.

Third Point:

This is just a variation on the first two points combined but critically important!

So what if the side signal has louder portions than the mid?

If it does, you have phase issues you need to address before you go any further. Your stereo mix, in cases like this, may have a "really cool" 3D, surround-like effect going on, but few people are ever listening in the sweet spot to a song, even if they listen in stereo. And these "effects" rarely translate to headphone listening.

But this doesn't address a more serious issue.

If anything is louder in the SIDE signal, you naturally have a weakness you need to address not just for the MID signal but your entire STEREO MIX.

You should note that this applies for 99% of pop recordings. Live, Jazz, and Classical recordings often follow different criteria to achieve a proper balance. Nevertheless, the reasons for monitoring still apply.

Mid side monitoring.

It’s simple.

It’s easy.

And it’s actually free!

So why create problems for your final master?

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