Help understanding this mid-side block diagram

[cinealta]

So, M/S recording allows you to vary the width of the stereo image *after the fact*, unlike X-Y recording. Also, an M/S recording will always sound good in mono.

M/S recording involves two mics. The Mid (M) and the Side (S). Both mics capsules must be close together (same plane, eg one above and below eachother).

The Mid mic faces straight ahead (typically in cardioid pattern). The Side mic faces left-right (in Figure 8 pattern). The front of the Side mic typically faces Left and the rear faces Right (by traditional convention).

The Mid mic will pick up sounds from both sides (Left & Right). Interestingly, the sounds from the Left will be exactly 180 degrees out of phase with the sounds on the Right.

You bring both signals into your DAW. To separate the L&R signals from the one Side mic, you split the signal into two signals in your DAW, reverse the phase of one of them and pan them hard Left & Right.

Now you can adjust how wide of a stereo image you want by increasing/decreasing the two Side signals.

Pretty cool.

[loujudson]

Originally Posted by hauntedclutter

I've been studying this m-s block diagram for a few hours now and feel pretty stupid because I don't understand it. Is the signal flow from top to bottom like a channel strip? If anyone could walk me through this I'd really appreciate the help. I know I'm just thinking of it completely wrong. Why are there only two channels and why is the level control in the middle? I would LOVE to see the light.

Here is a link to the diagram:
mid-side block diagram

If you buy the book and read it cover to cover the light may shine on you. It is ear training, not schematic reading. The signal flow is top to bottom, and very simple actually. Why and what to listen for are not so simple.

[rocksure]

Originally Posted by hauntedclutter

I've been studying this m-s block diagram for a few hours now and feel pretty stupid because I don't understand it. Is the signal flow from top to bottom like a channel strip? If anyone could walk me through this I'd really appreciate the help. I know I'm just thinking of it completely wrong. Why are there only two channels and why is the level control in the middle? I would LOVE to see the light.

Here is a link to the diagram:
mid-side block diagram

This tutorial I wrote has quite a bit on mid-side recording in it. Perhaps you might find it of some help?

Stereo-micing-techniques part 2

[loujudson]

People are responding with MS recording information - but the diagram in question is about mid-side processing, as used in mastering. There is a difference, and might be confusin the OP.

What are you trying to grok in the diagram, wnd why?
L

[hauntedclutter]

Originally Posted by loujudson

People are responding with MS recording information - but the diagram in question is about mid-side processing, as used in mastering. There is a difference, and might be confusin the OP.

What are you trying to grok in the diagram, wnd why?
L

Thanks loujudson,

I do own the book. This is the only section of the book (3 pages) that mentions M-S. It is a chapter about understanding the "spatial" elements of mixing and how M-S processing can help you hear and bring out elements of a recording that were originally masked.

I understand how to set up manual M-S processing in a DAW and how it works, but I am having difficulty relating it to the block diagram.

Since the schematic is top to bottom, what is happening after the level fader?
Is this the process of converting back to stereo?
I was just hoping someone could walk me through it a little. It just really frustrates me that I understand the text in the book and can set up a matrix myself, but I'm too dumb to "see" the process working in this diagram. Thanks again.