Mid/Side processing enables you to decode a stereo signal into two parts. The Mid channel contains the information that appears in both the left and right channels, and the Side channel contains all the information that is different between the left and right channels. Although there are several plugins that can do the decoding for you, like the free Brainworks bx solo plugin and the free Voxengo MSED plugin, and Mathew Lane’s DrMS, creating a Mid Side matrix yourself is an excellent way to learn more about using the concept of Mid Side Processing in Logic Pro. All you need is some routing skills, and the Gain plugin.

Manually Creating a Mid Side Matrix

1. Split a stereo file into a left and a right part (read this post on doing this in Logic, there’s a caveat). Put them on mono tracks 1 & 2. Pan at center.
2. Duplicate the left and right parts. Put them on mono tracks 3 & 4. Pan at center.
3. With the mono Gain plugin, invert phase on track 4.
4. For track 1&2, set Bus 1 as Output.
5. For track 3&4, set Bus 2 as Output.
6. Put an Aux Send to Bus 3 on Bus 1.
7. Put an Aux Send to Bus 4 on Bus 2.
8. Verify your Buses are mono.
9. Pan Bus 1 & 2 hard left, 3 & 4 hard right.
10. With the mono Gain plugin, invert phase on bus 4.

Making groups for tracks 1 & 2 and 3 & 4 comes in handy. You should now have something like this:

A Mid/Side Matrix, created manually in Logic Pro.

There you have it. You can control the Mid level with ‘mid’ group 1 (track 1 & 2). Control the Side level with ‘side’ group 2 (track 3 & 4).

Related posts:

Logic Pro’s Direction Mixer: The Mid/Side Trap Mid Side Processing: Solo The Sides – Part 3 Mid Side Processing: Solo The Sides – Part 1 Mid Side Processing: Solo The Sides – Part 2 Article: Recording and Mixing Mid/Side Tracks