[John Marsden]

Daft question
If I point two small ½ inch condenser mics away from each other  (Rode M5’s)
and then point a third microphone forwards at 90 degree to them (Rode NT2-A)
Can I use this as a sort MS arrangement? I know it’s not really what you should do. But just thinking of a back up plan if one of my two NT2’s should fail (ie get stolen!)

Ie do the two M5’s almost equal a figure of 8 arrangement  And given that can I just pan them right and left and use them to add wide stereo sound.

And then I got to thinking can I make the front mic xy and place a pair of mics pointing off to the right and left to create the wider ambient field.

Aim to use for classical trio or piano ensemble stuff in a hall.

Thanks to anyone with a suggestion
John

[Dinogi]

To be a proper MS you would need to flip the polarity of one of the side microphones. Otherwise it won't cancel when collapsed to mono.

[John Marsden]

I should try to align the mic diaphragms in the same plane so they will have no delay issue.
Would the fact they are pointing 180 from each other then mean they are already out of phase?
I shall try both and see which gives the best mono response.
Thanks for the advice

[Dinogi]

Actually, no. The outputs of your side mics would be still in phase and would be additive when they should cancel. That's basically the point of the MS technique. More than other techniques, MS seems to be an auditory illusion and not a verbatim reproduction of what happens in front of the mic's.

[Fletcher]

M/S... you're taking a figure 8 mic, splitting the signal [as there is only one output], taking that signal and flipping one side 180˚ out of polarity with the other side so -- when of equal level and put in mono, the two sides of [the identical signal] will cancel... the forward facing cardioid microphone being unaffected by the polarity reversal.

Even if RØDE built 100% "perfectly matched" microphones -- due to placement [spacing between the two capsules] they would never cancel 100%... they might get "close enough for jazz", but they will never 100% cancel.

This is not to say you shouldn't try the technique [who knows, it could be awesome for your application(s)], but it will NEVER be true "M/S".

Peace

[Alisatralp]

I have a simple sketch of the setup Id like to try. I was gonna try an MXL 990 for vocals, and a couple of SM57s for side instrument mics. Shuold we make a date for your practice space?

[sdelsolray]

To be a proper MS you would need to flip the polarity of one of the side microphones. Otherwise it won't cancel when collapsed to mono.

Not exactly, if you want to approach/emulate M/S.  Both side cardioid mics must first be mixed together.  That mixed track is copied/dupicated.  The mixed tracks are panned hard left and right.  One of the mixed tracks would have the polarity reversed.

An issue not yet discussed which makes using two cardioid mics (instead of the Figure 8 mic) more different for M/S is that the null at 90 degrees on a figure 8 pattern is many dB less than the null of the cardioid mics at 90 degrees.  If a pair of cardioid mics are used, the null sides have higher amplitude which is what the mid mic is supposed to capture and the result is less distinct separation.