MS (or Mid Side) is a technique that is quite complex and unorthodox compared to regular stereo miking techniques, although it offers some cool advantages and unique sound. MS works by splitting the signal into a middle channel and a pair of sides channels, left and right. The middle channel remains panned in the centre, and the side channels are spread hard left and right.
Recording with the MS technique requires a cardioid and a figure 8 patterned microphone placed as per the image below. The cardioid mic is directly facing the sound source, whilst the fig 8 microphone is turned 90 degrees to one side of the sound source, this means it is focusing more on ambience and reverberant sounds on the sides. As this mic is only carrying one signal, there is a method to split the two sides into an individual channel. This is done by duplicating the recording of the fig 8 mic and flipping that duplicate out of phase with the other.
In the laws of audio, the two recording should technically now be out of phase and cancel eachother out. Panning them each hard to left and right will then split the two and they will not add together. This should represent each side of the figure 8 microphones signal. With these sides still technically out of phase, we dial in the middle channel and it brings the sides back in phase. If that didn’t make sense here is the technical formula…
Mid + (+Side) = left channel
Mid + (-Side) = right channel
The mastering technique follows the same principle as the recording one, however it begins obviously with a stereo mixdown. From there you send the mix to a series of stereo auxiliary channels. Firstly, a send to an individual Mids channel, of which the output should be sent to a Master auxiliary. Secondly, on another bus path, send the mix to another pair of stereo auxiliary tracks, these will be the Side Left and Side Right (one of these must be phase inverted), they must also be panned hard left and hard right. These two side channels should then have their outputs sent to another stereo auxiliary, this will be the Sides channel, which will then be sent to the Master Auxiliary, which now contains the signal from the Mid and Sides. The purpose of the sides channel of the have transparent control over both the Left and Right.
Whilst this is very complex and convoluted it has a number of advantages for both recording and mastering…
- You do not need an exact pair of microphones as per the usual stereo miking pattern. (Benefit for recording)
- It gives you the ability to manipulate the middle and the sides separately.
- By changing the levels between the Mid and sides, you have direct control over the apparent stereo width. The more level of the sides you have in the mix, the great the width of the stereo field.
- It is able to some easily into mono.
Here is an example of a song with both a standard stereo mix with basic limiting, and a mastered version of the same mix with the MS technique. The song was project done with a friend of mine, Dom, it is a very basic little song and has a very ambient sound.
The main differences I noticed was the width, straight away the MS mastered version sounded wider and the vocals felt a lot more free in the centre. With the sides I added in some high end with an EQ and brought out more chimey brightness in the electric guitars. I will be using this technique in recording and mastering phases of my major project this trimester. Stay tuned for my next blog which will have the details and brief for the project. It will be an Indie Rock EP with a band called The Grüvs!!! In further blogs I will be investigating loudness standards for radio, Itunes and Spotify etc. Aiming to have my final project up to an industry level of quality.
Mid-Side (MS) Mic Recording Basics – Blog – Universal Audio. (2016). Uaudio.com. Retrieved 23 October 2016, from http://www.uaudio.com/blog/mid-side-mic-recording/
How to Record a Stereo Sound with MS Recording Technique. (2016). YouTube. Retrieved 23 October 2016, from https://www.youtube.com/watch?v=WutTY25fj-g
Pro Tools 10 Mastering Tutorial – MS Encoding. (2016). YouTube. Retrieved 23 October 2016, from https://www.youtube.com/watch?v=GbiTmD9BW6M