M-S micing

[j_howell]

I'd like to try this, but I'm a little confused with regards to encoding/decoding/whatever...mid + side? mid - side? wha?

I know I need at least one mic that'll do figure-8 (check-RCA ribbon), so what do I want to use for the mid part, and how do I go about it?

Aside from the whoop-ass RCA, my choice of mics is...well, pretty crap, really. I also have an MXL V63, and a couple of dynamics (EV 623 and RE-10) lying around...

[TimeStamp]

Many people swear by an omni in the mid position, but I've only ever used directional mics toward the source and I've been totally pleased. The matrix is actually a pretty simple thing to set up. Just bring up your mono mic like you would in any case, pan the ribbon to the side of its address (left/right), then bus that signal to a new channel that will be panned to the opposite side and phase flipped. Then just find a nice level for your two ribbon signals to sit against the mono (mid) mic. Sometimes it's fun to gate the side matrix, if you've got a big room and you want things to open up only when it gets loud. Shucks that your bad-ass mic is the ribbon, cause the bulk of your signal will still come from the mono mic.

[drumsound]

If you don't have a dedicated encoder you can print the 3 sources (Mid -SideL -SideR) to three tracks. Then put the mid in the center the the sides hard panned and bring them up evenly to adjust the width of the signal.

Ribbons make nice side mics BTW.

[RefD]

*rolls with spaced omnis for the room and cardioid mics for what's sitting in the middle*

however, i'd use near-coincident or maybe ORTF if i'm only using that for capturing the sounds.

mid-side is great for mono compatibility, but i certainly wouldn't consider it good stereo miking cos if the sources move around you'll never hear them moving in the field.

but i'm no fun.

[Professor]

Call me boring, but I'm still a firm believer that the two mics should be as close as possible to the same. The whole point is that the mics are supposed to pick up signals from various directions at different volume leves but at the same time. Then the two mics should be combined in the decode process so that parts of the sounds are reinforced and other parts are cancelled. And since phase relationships, timing, and frequency response are so important to how the process works, it seems like the results wouldn't work properly when the mics are as radically different as a modern LDC and a vintage ribbon.

But there's not really a reason to not at least try doing it. Just promise you'll try again later with more matched mics even if the results this time don't seem to do anything special.

I've listed the method and theory here lots of times on other posts, but I think this time I'll just defer right to the final word, from Wes Dooley & Ron Streicher. It can be a slightly dense read for some, but at least go through some of the "1: Concept & Theory" portion and most of the "2: Practical Application". And you should also get in close to really look at the detail on all those graphed combinations since that is how the signals decode at different volume levels. It's worth printing out, circling all of the "50-50" decodes, since those represent the Mid vs. Side at equal levels, and then just remember what the patterns & angles move to as the decode balance leans more towards the Mid or more towards the Side.
Oh, for those curious about the diagrams, the first set in Fig. 1 are kind of the 'short form' that give a cardioid, omni, or Fig-8 Mid mic at 70/30, 50/50, and 30/70. The next set in Fig. 2a-2i gives 5% steps from 30/70 to 70/30 with 9 different polar patterns.


-Jeremy

[A.David.MacKinnon]

The Re10 might be a good pairing with the RCA. I've been doing a session using Mid Side as the front of kit mics. I'm using an RE15 and an Apex ribbon. It sounds lovely. I'm finally getting more kit than cymbals (the drummer has a pretty light touch) and the RE 15 has enough zing to it that I'm not feeling bad about leaving my condensers in the mic locker.

Give it a shot. Those EV mics are better than people give them credit for. I'd happily trade a new 57 for an old beat up RE15 (any RE series mic really. Some PLs too.)

[msmith]

When I use MS, I have a coupla short little XLR splits(Y Cables) that I use. I usually use 414s or U87s, and I always roll matched, but thats just me. I use the Y Cable on my figure 8 mic and bring that back to 2 seperate channels on the board. Each hard panned opposite the other. I flip the phase on one and put the console in mono. Ill raise each fader and balance them until the image completely nulls. Thats the fader position, and I resist the urge to touch those two after that. Next bring up the cardioid mic dead center. Back to stereo monitor and place the mono mic where you think it should be (balance wise). Done. I think MS has a wonderful reallism. When its right, its right. For strings you can really capture the nuances of the instrument and the room working in tandem.

[cgarges]

Ribbons make nice side mics BTW.

So do condensers. Why do people always feel the need to talk about ribbon mics as the side mics in an MS configuration? Condenser mics have much more going for them in my opinion. If you want any sort of detail in your ambience, you're going to get much more of that from most condenser mics at a distance than with ribbon mics.

Chris Garges
Charlotte, NC

[Vogon]

...i certainly wouldn't consider it good stereo miking cos if the sources move around you'll never hear them moving in the field.

Eh? It's a stereo system...

[Nick Sevilla]

*rolls with spaced omnis for the room and cardioid mics for what's sitting in the middle*

however, i'd use near-coincident or maybe ORTF if i'm only using that for capturing the sounds.

mid-side is great for mono compatibility, but i certainly wouldn't consider it good stereo miking cos if the sources move around you'll never hear them moving in the field.

but i'm no fun.

Oops... bad info. Check the lovely link to the M-S techniques, here again for ya:

http://www.wesdooley.com/pdf/technique.pdf

It's actually MORE accurate than coincident (X-Y) techniques.

Try it for yourself. You'll be pleasantly surprised.

[Jay Reynolds]

From Dooley and Streicher, Section 4 - "Summary":
"All miking involves some sets of compromises."

I dunno why. But

[LeedyGuy]

Ribbons make nice side mics BTW.

So do condensers. Why do people always feel the need to talk about ribbon mics as the side mics in an MS configuration? Condenser mics have much more going for them in my opinion. If you want any sort of detail in your ambience, you're going to get much more of that from most condenser mics at a distance than with ribbon mics.

Chris Garges
Charlotte, NC

I would love to try a condenser. I have only used my Cascade Fathead in M-S since I tried my only other multi-pattern mic and it sounded like crap: SP B-3.

-Ken

[Nick Sevilla]

Ribbons make nice side mics BTW.

So do condensers. Why do people always feel the need to talk about ribbon mics as the side mics in an MS configuration? Condenser mics have much more going for them in my opinion. If you want any sort of detail in your ambience, you're going to get much more of that from most condenser mics at a distance than with ribbon mics.

Chris Garges
Charlotte, NC

+1 on the condenser use in MS. Much more detail.

[Professor]

Here's the deal with mis-matched mics as I see it:
The decode process for Mid/Side relies on the volume difference of the signals picked up by the two mics. If the Mid mic is louder then the image will be narrower - you're using more of the 'mono' portion of the signal. If you're using more of the Side mic the image should appear wider, although if you start to go too far the sound can get a little phasey because it's two out-of-phase copies of the same mic.
Now if you take that general rule and consider spreading it across the frequency spectrum you have to look at how the individual mics respond at lows, mids and highs. Fig-8 mics stay fig-8 across the whole spectrum although they will tend to tighten a little in the highs. Cardioid mics will tend towards omni in the lows and tighten up to hypercardioid or something similar in the highs. So Mid/Side is already expected to shift around a little across the spectrum, but if it gets a little more directional & wider in the highs then that's great since that's where most of the location cues reside.

Where I have trouble with ribbons as the side, is that I have seen the frequency response charts on ribbons, and they aren't flat - about as far from it as you can get. Mostly they look like one of those ramps for working under your car. Now if the Side mic drops off in the lows, the mid will be more prominent, and the signal will become more mono - but that's cool in the low-end because the sound itself is less directional. The trouble is really in the top end when the ribbon will drop off pretty sharply. There again, the Mid will be more prominent and the image will narrow, but that's where all the directional cues are residing. So you get a kinda stereo mid-range, without a real sense of the room around the instrument. Maybe that could work out if you're recording drums in a crappy room and want the ambience to collapse to a narrower mono in the very high stuff. But the outcome is also going to be very unpredictable in general.

But these are also the rantings of a guy who records a lot of acoustic instruments and sounds for productions that are generally delivered without any kind of special effects. So if I'm recording in stereo I'm not looking for a weird and wacky effect, I'm looking for clarity, accuracy, a sense of the room & space, and some movement in the stereo field. So M/S is what I'll reach for when I want a certain type of focus and the flexibility of width control in mixdown.

-Jeremy

[wikirecording]

You might find this article on WikiRecording helpful.

http://www.wikirecording.org/Mid-Side_M ... _Technique