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Author Topic: m/s --room reverberation and large choir recording questions  (Read 9420 times)

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Offline 2manyrocks

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I've never recorded in m/s and am having a bit of trouble figuring out how to ask the right questions.

Is it true that a hypercard pattern can be had from pairing a figure 8 with a card?  And it's adjustable in post recording?

Also read that one of the issues with m/s is that in recording a large choir, the center can be overdone compared to the edges of the choir?  Do you overcome this with flanking microphones? 

So m/s would be really good for a smaller ensemble, but not so much for a larger one of say 200 voices?



Offline voltronic

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Re: m/s --room reverberation and large choir recording questions
« Reply #1 on: May 09, 2015, 08:19:13 PM »
Now it's my turn to tell you to contact Boojum - he has been doing the center M/S with flanking omnis more lately from what he tells me.

I'm not sure about your hypercard comment.  What I can tell you is that with M/S recording in general, yes you can adjust the "dry/wet" balance in post.  I would recommend that you do not record through a M/S matrix and instead just keep them separate to make balancing in post easier. 

EDIT: I see you are asking about the M/S mode in the 70D.  Some pres and recorders have a M/S decoding matrix built in, for example Schoeps VMS preamps.  While this can be nice, my personal preference is to record the mid and side mics as separate mono tracks (or a hard-panned stereo track) and then decode them later in the DAW, either with a M/S plugin or just making your own matrix, where you duplicate the side (fig8) track and phase-invert the duplicate.  The center (card) is center panned, but the mid (positive phase) is panned hard left while the mid (inverted phase) is panned hard right.  See tracks 4-6 in the screenshot below.

As far as the large / small choir: I've used my colleague's Schoeps M/S setup several times to record his large (250+) and small (40-50) choirs, and I don't think it the size of the group makes a difference one way or another, at least from the relatively far back distances I record.  It's more the other problem - you can get too much hall sound, but you can easily dial that back by lowering the side tracks in your DAW.  I have a few mixes of the small choir I'm mentioning with the sides equal to the center, then dropped by 3 and then 6 dB I could post to illustrate this.
« Last Edit: May 09, 2015, 08:53:02 PM by voltronic »
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Offline voltronic

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Re: m/s --room reverberation and large choir recording questions
« Reply #2 on: May 09, 2015, 09:08:45 PM »
Here's a link to the project I'm mentioning.  I did not record this personally, so I have no idea about mic placement or distance - it was just sent to me for mixing.  The cardioid and fig8 were recorded as separate mono tracks at my request.
Schoeps MK4/MK8 > CMC5 > Zoom H6.  40-50 voice HS chamber choir in a medium-sized church.  This was for a local radio Christmas carol school choir contest, and sadly they chose a far inferior choir to this one to put on the air!
https://www.dropbox.com/sh/1qdzq25muzg20j0/AADznIP4w3VNc_JdvCzPs4RBa?dl=0
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Offline 2manyrocks

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Re: m/s --room reverberation and large choir recording questions
« Reply #3 on: May 09, 2015, 10:17:58 PM »
Nifty neato.  Seems like M/S offers the choice of cutting back on the room by cutting back on the S with a tradeoff of less fullness in the sound. 

When you record the 250 voice choir, how far back are you placing the mics?  Is m/s his choice of mic configuration?

How do you like m/s for choral recording v. what you're trying with the 4 mic array?

Offline voltronic

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Re: m/s --room reverberation and large choir recording questions
« Reply #4 on: May 09, 2015, 10:44:27 PM »
Nifty neato.  Seems like M/S offers the choice of cutting back on the room by cutting back on the S with a tradeoff of less fullness in the sound. 
Yeah, that's pretty much it.  But I think if you add omni outriggers as Boojum and others have done, you may be able to dial back the side of the M/S pair and add a different kind of hall ambiance back with with flanking omnis.

Quote
When you record the 250 voice choir, how far back are you placing the mics?  Is m/s his choice of mic configuration?
Well I only get to record that choir once a year, and the Schoeps M/S pair belongs to the choir's director.  Yes, that's his choice as they're the best mics he has.  They're placed in the only location I'm allowed by the video crew, which is halfway back in a large auditorium, fairly close to dead center.  It actually is probably the best place to record in there being that there are some groups on stage and others on the pit, so for an overall balance of the concert it works well.  Here's a sample of that big choir from last year's concert, recorded in that location with just the CM3s in NOS.  They really crank up the volume after 3:30.  The audience noise is because this is accompanying a senior slideshow.  Unfortunately I don't have a copy of the M/S recording to compare.
https://www.dropbox.com/s/mbhh379fabxh37f/Bridge%20Over%20Troubled%20Water.mp3?dl=0

Quote
How do you like m/s for choral recording v. what you're trying with the 4 mic array?
It's hard to tell - the two setups sound completely different.  Since I only get my hands on that M/S rig once or twice a year it's difficult to make a direct comparison, and sometimes I don't even get to hear those files as those mics go to his recorder instead of mine.  I like that the 4-mic array allows some balancing of the sound in post like M/S does, although less drastically changing the sound.  In a very reverberant space like in the M/S samples I posted, you can sometimes make it sound anywhere from a cardboard box to an airplane hangar.
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Offline 2manyrocks

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Re: m/s --room reverberation and large choir recording questions
« Reply #5 on: May 10, 2015, 01:58:27 PM »
A competent video crew could shoot around a mic stand. 

Where is the video crew pulling their audio feed?
« Last Edit: May 10, 2015, 02:06:43 PM by 2manyrocks »

Offline voltronic

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Re: m/s --room reverberation and large choir recording questions
« Reply #6 on: May 10, 2015, 02:43:40 PM »
A competent video crew could shoot around a mic stand. 

Where is the video crew pulling their audio feed?
First, it's a school and we have a student TV studio.  They use multiple cameras but are fixed on tripods.  If my stand were down in the pit, it would be in the way of the conductor for smaller ensembles that perform there and would be right in the shot for any of their 4 cameras.

Their audio is from an AT X/Y in the middle of the large choir just in front of the conductor, and sometimes they just set up one SM58 or similar on a stand next to one of the cameras.  Their videos sound awful, and there are professionals running this.  The director likes to only deal with mono.  I have offered many times to give them a stereo feed off of my FP24 or recorder.  Sometimes I dropbox the TV people my unedited recording for them to replace their audio with, but they have used it exactly once.  I may not be a professional recording engineer, but even when I was just recording with CA-14s into my M10 my audio was light years better than theirs.  It's very frustrating.
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Offline 2manyrocks

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Re: m/s --room reverberation and large choir recording questions
« Reply #7 on: May 10, 2015, 02:57:58 PM »
How is the video ultimately used? 

I assume then you have a director primarily concerned with how his video looks? 

We have a theater director focused on appearances.  His set changes make every play run twice as long as the script. 

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Re: m/s --room reverberation and large choir recording questions
« Reply #8 on: May 11, 2015, 07:56:03 AM »
With standard (two-microphone) M/S, you can adjust the amount of reverberation in the eventual L/R stereo mix. But you can only adjust it relative to the amount of reverberation that the "M" (forward-facing) microphone is picking up--which in turn depends on its location, its pattern, and the room. If the "M" microphone is placed too far back for its pattern and the room characteristics, then even if you leave the "S" signal out of the mix completely (giving you a mono recording), you will still have too much reverberation in the recording.

M/S can't compensate for overly distant (or for that matter overly close) placement, for the choice of an overly broad (or for that matter overly narrow) pattern for the "M" microphone, or for overly reverberant (or for that matter overly dry) room acoustics. When you go back to the reason it was invented in the early 1950s, when stereo LPs and FM broadcasts were first being planned, it is basically a method for making a normal mono recording (the thing that 99% of all listeners would hear back then) that also yields a stereo version. The stereo version would offer a greater net amount of reverberation--but that would be balanced by the listener's ability to localize sound sources in the horizontal plane, such that the overall clarity of the mono and stereo recordings would be subjectively more or less equivalent if you made good miking and matrixing decisions.

Being forced to place your microphones a considerable distance from a wide stage has its good and bad sides. The good side is that the distance tends to reduce any excess emphasis or focus on the performers at the front and center of the stage, which you might have with closer miking. The bad side is the loss of immediacy and clarity, and the inclusion of room sound that may not be pleasant in character. To some extent you can compensate by using an "M" microphone with greater directivity (e.g. for Schoeps, an MK 41 instead of an MK 4); the difference between a cardioid and a supercardioid is only moderate rather than night-and-day, but it can definitely be worthwhile.
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Offline 2manyrocks

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Re: m/s --room reverberation and large choir recording questions
« Reply #9 on: May 11, 2015, 10:09:53 AM »
Thank you for your helpful explanation. 

Two general followup questions.  Do you find m/s a suitable configuration for recording large choirs when you are free to place your mic stand anywhere or do you prefer another configuration?

Are there other mic configurations that could be more suitable for recording large choirs when one is forced to place the main mic stand at a distance?  A pair of mk41 in ortf for example?

Offline Gutbucket

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Re: m/s --room reverberation and large choir recording questions
« Reply #10 on: May 11, 2015, 10:45:44 AM »
Is it true that a hypercard pattern can be had from pairing a figure 8 with a card?  And it's adjustable in post recording?

Yes.  But it will only produce a crossed hypercardioid pattern at one point along the mix ratio continuum, resulting in one particular virtual microphone angle.  Both the virtual microphone patterns and angle between them change together as you vary the M/S mix ratio. With a mix ratio of 100% Mid, 0% Side, the virtual microphone output is two forward facing cardioids with no angle between them.  With a mix ratio of 0% Mid, 100% Side, the virtual mic output is two sideways pointing figure-8s.   So if your mix ratio is mostly Mid, you get a virtual microphone pattern closer to cardioid shaped without much angle between them.  If mostly side, the virtual mic patterns are closer to 8-shaped, with a large angle between them.  At mix ratios somewhere between those, you get virtual crossed hypercardioids at one particular angle and crossed supercardioids at a narrower angle.

Quote
Also read that one of the issues with m/s is that in recording a large choir, the center can be overdone compared to the edges of the choir?  Do you overcome this with flanking microphones? 

So m/s would be really good for a smaller ensemble, but not so much for a larger one of say 200 voices?

The first question is easier to answer since it's simply a technical one.  This part is more one of personal preference.  Here's my feelings on it, but they are only my own preference- 

When I listen to a large choir, the auditory impression I get is of a large, massed, big, spacious and enveloping sound, many voices blending together.  I usually want the recording to convey a similar auditory impression, so I'm likely to use a microphone technique which is good at conveying those aspects, and I'm likely use spaced mic techniques.

I don't care much for the monophonic reverberation component of most coincident techniques, which just doesn't sound very natural or good to me in a subjective sense, so I consider M/S as more of a useful modification of other techniques rather than a primary stereo configuration.  With a few exceptions, I'm less a fan of coincident techniques used on their own than spaced techniques used on their own.  So I start from spaced techniques and use coincident ones to improve on that when appropriate, and I may end up with a M/S pair in the center between a spaced pair.  Conceptually I'm starting with a wide spaced pair as the staring point, often adding a center microphone to solidify the center and provide presence rather than conceptually starting from a center coincident pair and adding flanking microphones.  Then rather than just the single center mic, I might also add a coincident sideways facing figure-8 to form a M/S pair as a way to adjust with the breadth of that center presence contribution.  That way, when listening back, I can adjust both the balance between the spaced mic pair and the center mic, and also the width and imaging of the center for best effect and a seamless blend across the playback stage.

So when I use M/S, it's usually to have the option of adding some width to a mono channel later.  I might want to add a bit of width to a mono spot mic, or to the center microphone contribution of a 3-mic stereo array.  But that's just what works for me.
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Offline Gutbucket

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Re: m/s --room reverberation and large choir recording questions
« Reply #11 on: May 11, 2015, 06:08:40 PM »
I'd like expand a bit more on what I posted above, to address a basic issue of the 'adjustable' aspect of the M/S stereo microphone technique, which I find is not generally well understood.

One of the frequently cited advantages of M/S is that the pickup pattern and angle between the virtual microphone pair are adjustable after the recording has been made.  That's true, but as explained above the relationship between pickup-pattern and angle is always locked, and you cannot change one of those things without also changing the other at the same time.  The real problem with that is not so much that the relationship is locked, even though it would be nice to be able to adjust angle and pattern separately.  The bigger problem is that the locked relationship between the two is the inverse of what we'd really like it to be.   At least if stereo is the primary intention of the recording rather than mono.

[self quote from my previous post above]
With a mix ratio of 100% Mid, 0% Side, the virtual microphone output is two forward facing cardioids with no angle between them.  With a mix ratio of 0% Mid, 100% Side, the virtual mic output is two sideways pointing figure-8s.   So if your mix ratio is mostly Mid, you get a virtual microphone pattern closer to cardioid shaped without much angle between them.  If mostly side, the virtual mic patterns are closer to 8-shaped, with a large angle between them.  At mix ratios somewhere between those, you get virtual crossed hypercardioids at one particular angle and crossed supercardioids at a narrower angle.

In terms of stereo, it would be much better if it worked the opposite way, so that the pickup patterns became more figure-8 like as the angle between virtual microphones became smaller, and more cardioid-like as the angle between microphones became greater.   That's the basic relationship between angle and pattern which we play off of each other in selecting appropriate stereo pair configurations, ignoring the additional aspect of spacing between the microphones of course since M/S is always coincident.

Because that relationship is locked in the inverse of what we'd like, M/S usually only really works well at one setting within in a rather narrow range of it's mix-ratio 'range of adjustment' for a stereo output.  The often touted advantage of being able to flexibility adjust angle and pattern after the recording has been made isn't really as great as we'd like it to be when the application is a main stereo pair.  If it works well near that one optimum mix-ratio great, but it's not because of any 'M/S adjustablility', it's because that one specific angle/pattern combination is appropriate for the recording situation.

That's not a problem when using M/S as a way of adding a bit of optional stereo width to a mono channel, where the goal isn't achieving a great stereo image on it's own, but rather smoothly and predictably adding stereo width and dimension to a mono channel without corrupting the mono channel or introducing phase complications.
« Last Edit: May 11, 2015, 06:15:04 PM by Gutbucket »
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Offline hi and lo

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Re: m/s --room reverberation and large choir recording questions
« Reply #12 on: May 11, 2015, 06:58:32 PM »
Thank you for your helpful explanation. 

Two general followup questions.  Do you find m/s a suitable configuration for recording large choirs when you are free to place your mic stand anywhere or do you prefer another configuration?

Are there other mic configurations that could be more suitable for recording large choirs when one is forced to place the main mic stand at a distance?  A pair of mk41 in ortf for example?

I can only speak from my limited experience seeing others experiment and listening to the results, but in my opinion M/S is junk for what we do and I would never bother with this silly configuration. It's a compromise in every sense of the word.

M/S was developed, in-part, for mono-capability and I challenge anyone to convince me why this would ever benefit the average concert recordist. I never listen to my recordings via mono playback and can't think of a reason why I ever would.

Moreover, I'm not a fan of coincident recording in general, i.e. X-Y. Maybe it's just me, but the timing delays of near-coincident techniques are very important to my ears and when those are gone, the recording suffers dramatically.

Offline voltronic

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Re: m/s --room reverberation and large choir recording questions
« Reply #13 on: May 11, 2015, 07:11:53 PM »
Discussions like this are why I come here. :)  I enjoy listening to the recordings of my friend's MK4/MK8 setup, but I think DSatz and Gutbucket may have explained why I've felt that, especially at a significant distance, I am preferring the sound of spaced omnis or near-spaced directional mics.  I hadn't considered that M/S was developed as a "mono with benefits" technique.  In a nice acoustic like the sample I posted, I think the M/S setup sounds good but it's more difficult to get a "realistic" sound, at least for me.  Next Thursday I will record that large choir again, and I hope to have the feed from the M/S to compare to my omni / card tracks.

DSatz: Totally on the opposite end of your suggestion of using an MK 41 in place of an MK 4, do you have experience with using an MK 2H in that application?  I have heard of using omnis as the mid mic in certain situations (which makes some things you've spoken of worse but others better), and the 2H seems like it could be a good compromise for more distant placement.
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Offline voltronic

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Re: m/s --room reverberation and large choir recording questions
« Reply #14 on: May 11, 2015, 07:26:38 PM »
Thank you for your helpful explanation. 

Two general followup questions.  Do you find m/s a suitable configuration for recording large choirs when you are free to place your mic stand anywhere or do you prefer another configuration?

Are there other mic configurations that could be more suitable for recording large choirs when one is forced to place the main mic stand at a distance?  A pair of mk41 in ortf for example?

I can only speak from my limited experience seeing others experiment and listening to the results, but in my opinion M/S is junk for what we do and I would never bother with this silly configuration. It's a compromise in every sense of the word.

M/S was developed, in-part, for mono-capability and I challenge anyone to convince me why this would ever benefit the average concert recordist. I never listen to my recordings via mono playback and can't think of a reason why I ever would.

Moreover, I'm not a fan of coincident recording in general, i.e. X-Y. Maybe it's just me, but the timing delays of near-coincident techniques are very important to my ears and when those are gone, the recording suffers dramatically.
When you say "what we do", remember that some of us here are Team Classical and in that context have enjoyed the benefits of M/S.  For amplified music, especially with crowd noise, M/S is probably very counterproductive.  I agree with your first sentence, except I would replace "M/S" with "X/Y".  I think M/S has the potential to sound good in far more situations than X/Y, which in my experience rarely sounds good even with good acoustics, quiet hall, etc.  I think manufacturers are to blame for promoting X/Y to the point where so many people think that's just "what you do" to record in stereo.  I'm not talking about cheap built-in mics, but more things like the Rode NT4.  I wish they had emulated the Schoeps 64G instead - the cost wouldn't have been that different.  While ORTF is not the right choice all the time either, I think percentage wise you're going to succeed more often than fail with it versus X/Y.
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Offline Gutbucket

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Re: m/s --room reverberation and large choir recording questions
« Reply #15 on: May 11, 2015, 07:40:11 PM »
Blumlein crossed figure-8s is an exception in my opinion, and a very good one.  It can sound fantastic, the problem is that it's rarely appropriate for most recording situations.  But when it is appropriate, M/S is a great way to do it.  Even if recorded as an X/Y pair instead of an M/S pair, it can be M/S adjusted afterwards without the 'inverse relationship' problem.  It is the one exception to that rule- the pickup patterns of the two virtual microphones do not change but remain figure-8s at all mix ratios, with only the angle between them changing.

I don't consider M/S to be much different from X/Y in terms of the resulting recording.  X/Y recordings can be 'ratio adjusted' after the recording has been made just like a M/S recording.  The most only significant difference, assuming all else is equal, is that with M/S the mid mic is pointed directly on-axis with the source, which can be helpful, and pair matching isn't important for stereo image stability as any mis-match artifacts will manifest symmetrically between the center and sides of the resulting stereo image rather than on one side verses the other.

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Offline voltronic

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Re: m/s --room reverberation and large choir recording questions
« Reply #16 on: May 11, 2015, 07:51:45 PM »
X/Y recordings can be 'ratio adjusted' after the recording has been made just like a M/S recording.
How do you go about doing this without affecting the L-R balance?  The only way I could think of would be a mid-side stereo width processor plugin.
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Re: m/s --room reverberation and large choir recording questions
« Reply #17 on: May 11, 2015, 08:41:14 PM »
That's it.

You first convert X/Y to M/S, then adjust the M/S mix ratio as you like, then convert from M/S back to X/Y again.  It's the same sum/difference matrix math going both ways.

Rather than panning from left to right it essentially allows for 'panning' between the center and the sides instead.

That's what a mid-side stereo width plug in is doing 'under the hood'.  You can do other things besides adjusting the mid/side level balance if you like, such as EQing the center differently than the sides, applying different dynamics adjustments or whatever.  You may have noticed that many plugins offer a M/S mode in addition to an L/R mode.  They just do the XY>M/S matrix conversion prior to doing whatever the plugin does, then do the M/S>X/Y conversion back again afterwards.
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Offline voltronic

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Re: m/s --room reverberation and large choir recording questions
« Reply #18 on: May 11, 2015, 09:01:19 PM »
OK, well in that case I have some experience doing that.  I've played with this in Izotope Ozone before which has that choice of modes - it is really handy to be able to EQ the mid and sides separately as you say. 

Perhaps it's odd that I've never used mid-side processing on an actual mid-side recording - I prefer to make my own matrix, maybe because visually it helps me keep track of what I'm doing.

I'm surprised to hear you say that you find M/S and X/Y recordings to sound similar.  I feel like they have the opposite issues to deal with: M/S can have tons of room ambiance at the expense of focus and clarity, and X/Y can have great localization but very poor ambiance and sense of space.  I'm generalizing of course, and my experience is usually recording at a fairly significant distance.  Closer to the source, I could see how the results could be much more similar, especially after some processing.
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Re: m/s --room reverberation and large choir recording questions
« Reply #19 on: May 16, 2015, 10:35:58 PM »
I haven't figured out how to directly quote Gutbucket's post in the omni mic bar thread, but I've copied it for discussion here:   

If you have the capability to record more than 2 channels and another microphone, give it a try with a single directional mic in the center facing forward.  A cardioid or supercard with a rolled off bottom end works well for that. You could simply clamp it to the supporting stand directly under the omni bar and best if your clamp allows you to place that mic about 8" to 20" forward of the omnis.

The setup pulls heat from music with ruthless efficiency like a good-cop/bad-cop interrogation team shaking down a perp.  The omnis contribute the spaced omni goodness- openess, naturalness, deep dimensional bottom-end and evelopement.  The directional mic brings out the clarity, details, and presence from the direct sound and solidifys the imaging.  Since it is pointing directly ahead it maximally excludes ambience and leaves that to the omnis, and instead focuses on the sound arriving from dead ahead.  It's a complementary match like sweet & sour, chocolate & peanutbutter, rock & roll.

Pull up the the omnis and pan them hard left/right, adjust balance (and EQ if you do that), then pan the directional mic to center and bring it up until it blends best and brings out the "oh yeah!" in you.  Also try going louder than you think the center directional should be and bring it down to what sounds good.  Play with it a bit and be amazed.

Avoid the strong temptation to add a typical near-spaced stereo pair in the center unless that's just for comparison.  If you feel you simply must use four mics instead of three, run the two in the center as X/Y  or M/S.. or point the fourth one directly away from the stage opposite to the center one and gain creative control over front/back depth, audience reaction and ambience.

Achieve mastery over the outdoor ampitheater, Ian, like a taper god.

Or just enjoy running two split omnis. ;)


I think this is pertinent to the discussion of m/s here and to Voltronic's four mic array thread as well. 

Ditch the m/s idea and go with omnis with a center directional mic? 

Offline capnhook

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Re: m/s --room reverberation and large choir recording questions
« Reply #20 on: May 16, 2015, 11:01:10 PM »
......go with omnis with a center directional mic?

Here's one that way, mixed live to two tracks:

https://archive.org/details/nrps2007-09-22.nak303.flac16

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Re: m/s --room reverberation and large choir recording questions
« Reply #21 on: May 18, 2015, 10:51:39 AM »
Ditch the m/s idea and go with omnis with a center directional mic?

Another way of thinking about it is that spaced omnis with a center directional is only one figure-8 away from being MS + spaced omnis.  For me the two spaced omnis are my starting point, and adding a directional mic in the center improves upon that significantly.  Those three channels are the core of my setup and anything else in addition to that core-3 is gravy.  From there it depends on how many channels I have available to me and what else I would like to do. 

If I'm recording 4 channels, the three most attractive good options for that 4th channel are: a mono SBD feed, a figure-8 coincident with the center directional (forming a M/S pair) or a rearward facing cardioid.

I typically choose a rearward facing cardioid for more control over direct/reverberant balance, front/back dimension, audience reaction and room ambiance.  I'm happy with the imaging I get from balancing the contribution of the omnis and the center directional, so control over those things is more useful to me than turning the center mic into a M/S pair for sharper forward imaging.  And if I'm getting a SBD feed, that's usually going to another recorder.

After that, I'd consider adding a fig-8 to the forward facing directional for some M/S width adjustment if recording more than 4 channels.  I'm looking forward to playing around with the pending Naiant figure-8 as lightweight and inexpensive way of doing that.

I'm surprised to hear you say that you find M/S and X/Y recordings to sound similar.  I feel like they have the opposite issues to deal with: M/S can have tons of room ambiance at the expense of focus and clarity, and X/Y can have great localization but very poor ambiance and sense of space.  I'm generalizing of course, and my experience is usually recording at a fairly significant distance.  Closer to the source, I could see how the results could be much more similar, especially after some processing.

It's all in the M/S ratio.  M/S with no side but all mid is 100% forward-facing Mid microphone, presumably a directional mic.  If that Mid is a super or hyper (or a shotgun) it's going to have the most focus and clarity of anything you could do from that particular location.  By contrast if you take an X/Y pair, and either point the mics directly to the sides 180-degrees apart, or convert a more typically angled X/Y recording to M/S and adjust the ratio to 100% Side, you're going to hear a lot of ambient room information without forward focus, the equivalent of a single sideways facing figure-8.
« Last Edit: May 18, 2015, 10:54:53 AM by Gutbucket »
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Offline 2manyrocks

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Re: m/s --room reverberation and large choir recording questions
« Reply #22 on: May 18, 2015, 12:59:35 PM »
I very much appreciate your taking time to help me understand this.  This is very helpful. 

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Re: m/s --room reverberation and large choir recording questions
« Reply #23 on: May 18, 2015, 02:56:45 PM »
Happy to help.

Others are working from sort of the opposite conceptual starting point than I am.  They're beginning with a coincident or a near-spaced stereo pair, and building upon that by adding the spaced omnis.  Some of the solutions end up being the same working either way, for example a M/S pair between spaced omnis.  But they get to that solution in a different way, and with a different emphasis.   

That way prioritizes the stereo pair in the center over the wide-spaced pair as the foundation of the recording, then builds upon that.  That's a logical extension of standard taper stereo microphone setups, and I think partly explains why a near-spaced pair with spaced omnis added to it is such a common four mic main setup around here.  My approach prioritizes the spaced omnis as the foundation and builds upon that, so it opens up various less specific options for what is added in the center.
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Better recording made easy - >>Improved PAS table<< | Made excellent- >>click here to download the Oddball Microphone Technique illustrated PDF booklet<< (note: This is a 1st draft, now several years old and in need of revision!  Stay tuned)

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Re: m/s --room reverberation and large choir recording questions
« Reply #24 on: May 18, 2015, 03:10:53 PM »
That's looking at the different approaches in terms of how they are applied.  In terms of the different underlying philosophies, starting with the center pair and adding omnis prioritizes stereo imaging over other aspects.  By contrast, my approach prioritizes control over the direct/ambient balance over imaging.  Neither approach excludes control over the other stuff, it's just where the emphasis is placed and the additional flexibility is leveraged.   To me the direct/ambient balance is a more critically important thing I'm happy to gain a bit more control over.
musical volition > vibrations > voltages > numeric values > voltages > vibrations> virtual teleportation time-machine experience
Better recording made easy - >>Improved PAS table<< | Made excellent- >>click here to download the Oddball Microphone Technique illustrated PDF booklet<< (note: This is a 1st draft, now several years old and in need of revision!  Stay tuned)

Offline phil_er_up

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Re: m/s --room reverberation and large choir recording questions
« Reply #25 on: May 18, 2015, 03:25:06 PM »
......go with omnis with a center directional mic?

Here's one that way, mixed live to two tracks:

https://archive.org/details/nrps2007-09-22.nak303.flac16

Thanks to all for this discussion.

===========================================

Checked the NRPS 9-22-07 recording and it states:

"NAK CM-300 x3 (CP-3, CP-1, CP-3) -> mic/line mod MX-100 -> oade line-mod SBM-1 -> Sony TCD-D8 -> DAT"


What was the spacing of the mics and were they all A-B?

===========================================

Thanks.
« Last Edit: May 18, 2015, 03:27:38 PM by phil_er_up »
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Re: m/s --room reverberation and large choir recording questions
« Reply #26 on: June 14, 2015, 09:14:14 AM »
I was just looking back at this thread and realized that something important was left out of the discussion: If your main activity as a musician is to sing in choruses or to conduct a chorus, you probably want a recording that spotlights the chorus, makes them the heroes of the evening, and spreads them all the way across the stereo image so that each member of the chorus can hear just where he or she was. Even though the orchestra is in front of the chorus, and sometimes plays louder than they sing, you want the chorus to have the sole focus whenever their precious mouths are open. You want to hear words; you want to hear what kind of spirit the singers are projecting; you practically want to hear what colors they were wearing. The rest is accompaniment (from that perspective).

The "problem" with a simple, two-microphone, coincident (including M/S) or near-coincident recording is that it will rather realistically portray the balance of the musical event according to the microphones' location. But such realism isn't everyone's goal. For that reason the idiom has evolved in which the chorus is miked by several hanging spot mikes--typically at least three, and maybe four or five. By the time you mix enough randomly-phased sound into a recording, the listeners's brains will no longer expect phase perceptions to make any sense; instead, the senses are beaten down to where they respond to amplitude (prominence in the mix) alone.

The result may well be a technical horror if you're a purist, but it will get you asked back to record the next concert. So think carefully about whether you want that or not ...

--best regards
« Last Edit: June 14, 2015, 09:16:21 AM by DSatz »
music > microphones > a recorder of some sort

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Re: m/s --room reverberation and large choir recording questions
« Reply #27 on: June 14, 2015, 01:30:03 PM »

By the time you mix enough randomly-phased sound into a recording, the listeners's brains will no longer expect phase perceptions to make any sense; instead, the senses are beaten down to where they respond to amplitude (prominence in the mix) alone.

The result may well be a technical horror if you're a purist, but it will get you asked back to record the next concert. So think carefully about whether you want that or not ...


 :thinking:

I want that.

Now I know why that works for me.....thanks DSatz
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and being beautiful and making the world a beautiful place through your actions.
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"It'll never be over, 'till we learn."
 
"My dream is to get a bus and get the band and just go coast to coast. Just about everything else except music, is anti-musical.  That's it.  Music's the thing." - Jeb Puryear

Offline 2manyrocks

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Re: m/s --room reverberation and large choir recording questions
« Reply #28 on: June 14, 2015, 06:03:23 PM »
The architecture of some newer, larger churches seems to dictate the use of multiple mics for sound reinforcement.  The reason I say this is because they incorporate these fixed choir lofts at the back of the platform that seem linear and leave no space for instruments except the space on the platform in front of the choir.  By the time it all gets processed through the mixing board, I'm not sure what we have.  The acoustics of some of these boxy church sanctuaries appear dependent on PA systems. 

Am I being too cynical, but why spend much on a recorder and mics when a soundboard patch is about what we're going to get?

The local 20-30 member choir in the 1880's sanctuary---is a different story.

 

 

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