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Re: Can you monitor mid/side in the field without an M/S matrix?

Subject: Re: Can you monitor mid/side in the field without an M/S matrix?
From: "Flawn Williams" flawn1951
Date: Tue Jan 28, 2014 5:37 am ((PST))
Emanuele=97

There are a lot of resources on the Web that describe Mid/Side decoding. On=
e useful one (apart from its careless but hardly unique misuse of the term =
=91phase=92 where =91polarity=92 is the correct concept) is at:

http://www.bhphotovideo.com/indepth/audio/tips-solutions/recording-mid-side=
-microphone-configuration

Scroll down to the =91decoding=92 section to see the details.

If you want a graphical reference, go to Google Images and search =93MS dec=
ode=94 or MS Matrix=94.


Basically here=92s what you do to decode M/S to L/R:

--Bring in your mid and side signals onto separate mono tracks.

--Pan the Mid track to the center.

--Pan the Side track all the way to the left.

--Duplicate the Side track, invert the polarity (or =93flip the phase=94) o=
n that track, and pan that track all the way to the right.

--If possible, link the volume faders for the two Side tracks so they are a=
lways equal in setting.

All three tracks should be routed to the same stereo output or bus. What wi=
ll emerge on that bus is decoded left/right stereo.

You can raise or lower the Mid track for more or less center intensity, and=
 raise or lower the Side tracks in tandem for wider or narrower image.


Now, the less intuitive trick:

If you set up an identical configuration of three tracks, but route Left/Ri=
ght audio into it instead of Mid/Side audio, what will emerge from the trac=
ks is a Mid signal on the left output and a Side signal on the right output=
.

So if the signal you recorded from your MS mic was already decoded in the m=
ic or in the recorder, or if you have any other normal stereo signal that y=
ou want to rebalance the middle vs. the sides:

You can send that left/right stereo signal into a set of three faders set u=
p as above, to derive Mid and Side signals, and route those to a stereo bus=
. You probably will leave all three of these volume faders set at unity gai=
n.

Then route that stereo bus into another set of three faders set up as above=
 to re-decode the Mid and Side signals into left and right. You can manipul=
ate the faders on this second group to adjust center intensity and image wi=
dth.

=97Flawn





On Jan 28, 2014, at 4:42 AM,  wrote:

> 1a. Re: Can you monitor mid/side in the field without an M/S matrix?
>    Posted by: "Emanuele"  lamacchiacosta
>    Date: Mon Jan 27, 2014 2:05 am ((PST))
>
> Hi Flawn,
>
> that sound interesting.
> Could you please explain more or do a step by step guide for it so we
> can try at home what you are pointing out?
>
> Thanks.
>
> Emanuele
>
> On 26/01/2014 14:17, Flawn Williams wrote:
>>
>> Widening the image is a little trickier and involves using a =91stereo w=
idth=92 plug-in, or knowing how to set up faders on an audio app=92s mixer =
to route the signals through MS processing TWICE: once to convert your deco=
ded stereo file back to Mid and Side signals for rebalancing, then again to=
 re-decode to left and right signals. (BTW this method can be used to narro=
w or widen ANY stereo recording, not just ones that use Mid and Side mikes.=
)
>>
>> =97Flawn







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