Thanks Ty,

I'm unclear about something. When you say that you can't manipulate the stereo breadth as you can with M/S, are you speaking of the difference between two mics in a coincedent array versus audio from a single M-S microphone?

Michael Hamilton

Nate,
When the M-S mic does the matrixing and gives me LR stereo output does
the mid become one channel and side become the other? If so will I be able to change the side from - to + per Steve House in my nle even though the side comes into it as one channel?

Michael Hamilton

Hi Mike,

Yes. In M/S you have the mono Mid mic you can always go to. That a bit different than monoing an XY because neither mic in XY is pointed directly at the source, (if there is a single source.)

M/S, when dematrixed through three channels on a console as elegantly described earlier in this thread by Steve House, lets you go from mono to very wide (and usually noisier), depending on the shot itself. That's done in post after they decide which shot they may be going with. You get a wide shot, you might want a wider sound field. If you're on a closeup, the typical way to do ambi is to make it a more narrow stereo spectrum.

Of course, over in France, I have learned they sometimes do dialog in M/S, which means relying on the Mid for the meat and adding the Side for the potatoes (pomme de terre?). I'm not sure what that sounds like in scenes where there a lot of boom movement. It might get pretty wacky. OTOH, maybe the boom technique changes to put the mic sort of in the middle of the action and expectng the Side to cover anyone not directly under the mic. If you weren't in MS and expecting to use the Side channels, you'd be missing some dialog (or it would be off axis) from anyone you weren't pointing the Mid mic at.

Z'at make sense?

Regards,

Ty Ford

right. ty's talking about 2 mics in an m/s array, as opposed to mics like i mentioned (which are really 2 mics in one handle.)

the sony i talked about does what steve described. the "left" and "right" it gives you are the mid + side, and the mid + phase-reversed (-) side. it's got an "angle" switch (wider or narrower) which basically chooses the faux-stereo spread before you start recording. if you wanted to further manipulate the spread after recording, it would be a pain.

let's see...if you summed the left and right channels, the + and - side would cancel itself out, leaving you with just the mid. put that aside for a second and duplicate it. go back and take the copy of the left channel (you copied it before summing it with the right.) now take one of your mid tracks (l+r summed,) and phase-reverse it. i'm pretty certain you can do that in soundtrack pro.
okay, now add the -mid to the original "left." this will cancel the mid, leaving you with just the side.

so you've basically un-matrixed the faux left and right to get back to the actual m and s signals that the mic elements picked up. (or a weird-sounding mush of phase cancellation and digital artifacts.) i have no idea if this would actually work, but it seems like it makes sense on paper.

just thinking about that makes my head hurt. the better m/s mics (or using a pair...) will give you the actual m and s outputs, leaving you to deal with the matrxing yourself, like barry said.

My head hurts now two. I need time to digest this but am really greatfull for everyones contributions.

Thanks
Michael Hamilton

M/S micing can be achieved by using separate Mid and Side mics or with some mics aready configured for M/S that have both capsules in one body.

Neumann RSM 191 (gorgeous sounding but pricey)
The Sennheiser 418s
Sanken CSS-5
AT 835ST (I think).....come to mind.


If you have a mixer like the Sound Devices 442, you can record in M/S but monitor in regular stereo because it has a built in matrix for the headphones. It also has another matrix so you can convert M/S mics to s regular stereo output.

Regards,
Ty Ford

so can we say that: without a mixer we can not use MS mics ? because it has two 3pin xlr output. when I want to plug to camera xlr inputs I need to switch any of two, not both at tha same time, or cameras (such as XL2) does sound mix among the two inputs ?

am I right ?

regards
alkim.

Well you can record MS directly to the camera, one mic per channnel, but then you'll have to dematrix them in post.

And monitoring will be weird unless your mixer will dematrix the M/S.

Regards,

Ty Ford

Not necessarily. When you say "M/S mics" are you talking about single-unit stereo mics that use the M/S principle but do the matrixing inside the mic's own electronics or are you talking about two separate microphones, one cardiod and one figure-8 mounted together on one stand? If it's the former the two cables coming out of the microphone have already had the M/S signal mixed inside the mic to create the left and right channels and you just plug 'em in to the L/R inputs on your camera or recorder like any other microphone pair and fageddaboutit. If it's the latter you will need to do the matrixing yourself to combine the M/S signals in order to derive the left and right stereo channels. This can be done while recording the original using a mixer before sending it to the recorder or camera if you have a mixer with the necessary circuitry or you can record them as two source master tracks which will then need to be mixed in post before they become proper sounding left and right stereo channels. If you're doing it in post you do it in your NLE using the method I mentioned earlier in the thread, you can send the signal out of the interface through a hardware matrixing circuit if you're using an audio workstation and interface that allows for looping a signal out through external device sends, or you can use any of a number of software plugins available for audio and video workstations that do M/S decoding in software if you use an NLE that supports plugins.

I talk about one cardoit and ona figure-8 together, and two 3 pin XLR output, pne is for cardoit and other is for figure-8. so will I plug these two outputs to two inputs? such as XL2 has two inputs. camera record seperate channels, and then I dematrix in post ? but without a micer How I monitor on XL2 camera. is there any option switching any source for monitoring ?

another question:
many MS mics has two 3pin or one XLR-5M outputs, such as AT815ST, Neumann RSM 191 etc. each of these outputs represent one element ? if so, if I plug only cardoit element to the camera, MS mic behaves like mono shutgun ?

thanks,
alkim.

[QUOTE=Alkim Un]I talk about one cardoit and ona figure-8 together, and two 3 pin XLR output, pne is for cardoit and other is for figure-8. so will I plug these two outputs to two inputs? such as XL2 has two inputs. camera record seperate channels, and then I dematrix in post ? but without a micer How I monitor on XL2 camera. is there any option switching any source for monitoring ?

**You monitor though the headphone jack as always, but it will sound weird. Rely mostly on the M channel and keep good levels.

another question:
many MS mics has two 3pin or one XLR-5M outputs, such as AT815ST, Neumann RSM 191 etc. each of these outputs represent one element ? if so, if I plug only cardoit element to the camera, MS mic behaves like mono shutgun ?

**Pretty much. The AT 835ST is shorter and better than the AT815ST and both have a switch that lets you choose mono shotgun or XY stereo or MS.

Please visit the online archives on my website for my review of the mic.

Ty Ford

I finally got a MKH 418S MS and found that I could monitor the M channel on my XL2 by pulling the headphone jack half way out of the plug.
I bring the DV signal into FCP just like any other, and wind up with a left and right stereo channel, M on one channel and S on the other. Then I duplicate the S channel, and place the dup on a third track in the timeline.
I pan the S channels in opposite directions, and make sure the M channel is centered. It sounds great, but I'm not sure if I'm doing it right. It seems as if there should be more stereo spread but I guess thats what a single M/S mic gives you.
When I bring down the two side channels I get a very strong and clean middle channel. I can stand about six feet away from the mic in a noisy environment, talking at a normal level and it sounds almost as good as a lavalier.
There is a draw-back though. Does anybody know of a 7-3pin XLR converter that I can use to hook up to a plug-on transmitter?
As far as I know, If you just want to go hand-held with a reporter there is know way make this mic wireless.

Michael

Sounds like you left out one step in your NLE. After you have duplicated the S track, invert the phase on the duplicate. The exact mix is L=M+(+S) and R=M+(-S) (Assuming that when you recorded, the "front" of the figure-8 side mic was pointed stage left.)

persactiplopoly!

Ty Ford