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Old April 30th, 2011, 07:49 PM   #16
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Re: Stage Mic Placement for avoiding Phase issues

I'd say it's about 60' across, so in plan D the outriggers would be 15' from the center XY but 30' apart from each other, pointed out. The "25"s are percentages.
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Old April 30th, 2011, 08:01 PM   #17
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Re: Stage Mic Placement for avoiding Phase issues

Adam,

I think it would be preferable to be hanging, but as low as possible, rather than in the pit at a level with the stage floor. Of course it depends on the production, but remember that someone downstage can block the sound from someone upstage. If the mic is up above the actors' head height, that won't be a problem.

Also, there is one advantage to being a bit farther from the lip of the stage. The relative distance of downstage actors and upstage actors will be more uniform. (That explanation sounds confusing, so let me elaborate.) Let's assume your stage is 20' deep. If your mic is at the lip, and the actor comes downstage to within 3' of the lip, then he's 3' from the mic. If he goes upstage, he's 20' from the mic. That's a 20:3 distance ratio, or 6.67:1. If your mic is over the 3rd row, let's assume that is 20' from the lip. If the actor comes downstage to within 3' of the lip, that's 23' from your mic. If he goes upstage he's 40' from your mic. That's a 40:23 ratio, or 1.74:1. So there will be much less variation in level between upstage and downstage action. This is more like what the audience hears, after all.)

Of course a disadvantage of being over the 3rd row is that the crowd noise will be louder, relative to the stage action. You can somewhat remedy that by using mics with a good directional pattern. (And no matter where the mics are, you will have to manually duck the gain during applause.)

Also over the 3rd row, you will have more reverberance in the sound, so the action will sound a bit more distant. Balancing that, the downstage and upstage action will be more uniform; it won't sound as if someone is jumping out of your lap and going into the back yard. Again, proper directional mics will reduce that reverberance somewhat.

I think it would be worthwhile trying to hang a cluster of 2, 3, or more mics, on the centerline, back where you feel it's possible (over the 3rd row). I would fan them out, but keep the heads as close together as reasonable... say within 12" or so. (This will eliminate any potential phase/comb filter problems.) Depending on how far back you are, and how wide the playing area is, you might need a group of five to cover the entire stage. Probably slightly lower gain on the center mic, since it is slightly closer than the side mics. Try a test recording there and see what you have to work with. It will not sound like a Broadway cast album, but it might be a fairly realistic archival recording.

(Admittedly this is partially guesswork. My actual experience was (a) recording mostly bands or a very few musicals, with hanging or tall-stand mics, and (b) dialog reinforcement on stage shows. Your particular dilemma is in a gray area somewhere in between.)

Given that PZMs are ruled out, I definitely cast a strong vote for hanging mics, rather than low stands! Does anyone else concur?
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Old April 30th, 2011, 08:11 PM   #18
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Re: Stage Mic Placement for avoiding Phase issues

Good points all. The added reverb and audience concerns me, as it is those very things I'm trying to minimize. But we'll give it a shot and see how it sounds.

The ratios make sense and I've thought about them, but I'm not convinced of how this will pan out in practice. If there's some arbitrary point away from the mics beyond which the sound just sucks, it seems to me the hanging mics would suffer from this most if not all of the time. If 90% of our action is within the first 10' from the lip, the mics on the floor would pick up most of it and the hanging mics wouldn't. But I get the ratio thing. Frankly, at the distance of the hanging mics, our on-camera shotguns are closer.

Thanks.
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Old April 30th, 2011, 08:27 PM   #19
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Re: Stage Mic Placement for avoiding Phase issues

Hmmm.

As I said, I mostly did school band recordings, with very few musicals. With band music, you expect to hear the hall as well.

It will depend hugely on the acoustics of your auditorium... whether it's boomy or reasonably dead.

And also on the directionality of your mics.

Is all the action really that far downstage? And yet across a 60' width? Did I read that right?

Where are your cameras? Heaven forbid they should be anywhere in the center of the room, where the audience would see them. Closer than the third row?
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Old April 30th, 2011, 09:37 PM   #20
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Re: Stage Mic Placement for avoiding Phase issues

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Originally Posted by Adam Gold View Post
Seems there are a lot of opinions on this... Seems like every ten posters will give 11 different opinions.
With all due respect to the knowledgeable pros here I'd suggest you ask people who do pro audio first.

Remote Possibilities in Acoustic Music & Location Recording - Gearslutz.com
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Old May 1st, 2011, 12:19 AM   #21
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Re: Stage Mic Placement for avoiding Phase issues

Kirk, thanks for the link. As I mentioned, I've spent several days (actually months) on the web reading up on this, including the forum you directed me to. That's where I got my observation about the diversity of opinion on all matters audio.

Greg, we usually have two cams behind the back row, about 50 feet from the stage, on either side of the booth, which is centered behind the back row. We also have two cams on the sides, on a platform behind the fifth row on the side seating areas. There's a small half wall behind each platform which hides our cams pretty well. The theatre was designed by some big-shot acoustical designer who I think did the main Symphony Concert Hall here in Seattle. The walls are covered with all these pyramid-shaped acoustic reflecting panels and it sounds great live. It's just when we try to make the sound stick to the videotape that we have issues.

Here's the floorplan. The proscenium itself is actually the very bottom of the picture with the main part of the stage not shown.
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Old May 1st, 2011, 08:07 AM   #22
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Re: Stage Mic Placement for avoiding Phase issues

Depending on which hat I wear for these kind of productions, I shift my stance somewhat. As a sound recordist, I want the absolute best sound - and I want microphones close in for clarity. If I'm the lighting designer, the damn microphones the sound designer wants to dot around get in the way, and the sound people always want a silent stage, something my moving lights are pretty poor at doing! If I'm the production manager, I've got all these people wanting priority, yet I've also got a duty to the audience who have paid to see the show, and obstacles are going to generate complaints. I've got people complaining because somebody keeps waving a Jimmy Jib in front of them and wants either unobstructed vision or a refund. The sound people want no noise, the lighting people want to make some, and the video people object to the light levels, the obstructions from mics pointing up from the float trough, and dangling down from the bars intruding into their shots.

At some point, a decision gets made and some things are compromised. A big stage and good sound from microphones on the periphery is always going to be a compromise. We all have our own solutions, usually built up by doing it wrong at some point. This is why I tend to NOT design around flown mics - I really hate the hard reflections from the floor - it always impacts (to my ears) on speech. I could live with a few shotguns for certain locations - perhaps for soloists - if the devils could learn to stand on a mark.

There's a big range of different techniques to be considered - and selecting the right one is tricky. One good for music is rubbish for speech. One good for a small stage falls apart on a wider one, where time delays due to distance become significant. Audiences can mess up a great set-up when they arrive, as their component was missing in the rehearsals.

My usual technique is simply to work out where the people are, and the see how close you can get the mics. Distance is the enemy to clarity.
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Old May 1st, 2011, 09:13 AM   #23
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Re: Stage Mic Placement for avoiding Phase issues

Adam,

I am a bit puzzled by one thing. When we first talked about hanging mics, you said the closest you could get them was house center, over the third or fourth row of seating. You also said your cams are at the extreme sides, behind the fifth row.

But just now you said

Quote:
Originally Posted by Adam Gold View Post
Frankly, at the distance of the hanging mics, our on-camera shotguns are closer.
I don't understand how fifth row at the side walls is closer than third row center. IMHO that just does not compute.

At any rate, I'm really running out of ideas. As I think you realize, you have ruled out a lot of options. I hope you will pick one approach, and make a test recording. Then either refine or discard that approach. (Or, if you have infinite resources and patience, try two approaches at once, and compare the results.)
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Old May 1st, 2011, 11:56 AM   #24
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Re: Stage Mic Placement for avoiding Phase issues

Yeah, I haven't actually measured all the distances with a tape, and looking at the chart it's hard to envision, and perhaps my statement was a bit of hyperbole. But if you envision performers at the corners of the apron in front of the proscenium, you can see where you might have that situation. And the hanging mics would be so high up that there'd be additional distance there. Cams 2 and 3 on the graphics are accurately represented, although as you can see the position of #3 is somewhat fluid, depending upon whether we have a wheelchair in the house -- we often have to pack up and move five minutes before the show.

Really appreciate all the ideas from everyone. It's just going to be a bit of trial and error, I guess.
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Old May 1st, 2011, 12:34 PM   #25
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Re: Stage Mic Placement for avoiding Phase issues

Adam, I'll throw in just one more thought. It concerns what I will call "perspective."

With four cameras, I suspect that your final video includes a fair number of MCU or CU shots. With the camera perspective this close, if you want the audio perspective to match, you need close micing. But close micing is a challenge because some of the action takes place upstage, yet you've ruled out wireless and PZMs.

If you were just shooting wide or medium wide from out in the house, then I think an archival audio recording from "third row" perspective would match up pretty well. But "third row" audio does not match the perspective of CU camera shots. Therein lies the rub.

This may seem (or may be) OT, but based on the audio sample you submitted, and what you've said over many posts, I think "perspective" is part of the difficulty.

Again, good luck!
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Old May 1st, 2011, 06:14 PM   #26
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Re: Stage Mic Placement for avoiding Phase issues

Greg, you're exactly right -- 90% of our finished video is footage from 2 and 3 -- and this is what makes this whole situation all the more frustrating. I'd love to use head mics but they're been ruled out way above my pay grade, and while I have nothing in theory against PZMs, you've seen from the samples I sent you that they just don't work well, especially upstage. Would better boundaries, like the ones Paul recommended, work noticeably better? Perhaps, but I doubt it. You just can't get that intimate sound from ten feet away. I've learned the cheapest crappy mic in the world at 12" will sound better than a million dollar Sanken at 15 feet.

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Old May 2nd, 2011, 09:16 AM   #27
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Re: Stage Mic Placement for avoiding Phase issues

Adam,

First of all, that's a nice (if rather wide) small auditorium. Only about 340 seats. The students should be able to fill that easily without any amplification. If they cannot project out into that size house, they should not have lead roles. In terms of reinforcement, there should be no need for body mics. Therefore, the only real reason for body mics would be for recording, so I'm starting to understand the teacher/director's objection. It's not a Broadway show in a 2,500 seat house.

The third row appears to be only about 10' from the lip, about 20' from the proscenium. If you hang your mics that close, and get them down as low as possible, I would think that you could easily pick up any stage action.

Out of curiosity, where is the pit area you talked about? The first row appears to be only about 3' from the stage. I don't see any place for an orchestra between the stage and the audience seats.

Actually, I don't think a "Broadway cast album" recording, with body mics, is realistic for high school students in this venue. That will capture something that nobody actually saw, it won't capture the students' actual performance. Given that you seem to have no concerns about expense and time, you should be able to get a good archival audio recording of the performance. If it then bothers you that the real audio doesn't match your XCU shots of the performers, perhaps the issue is that the camera shots are unrealistically close to match the audio in this situation.
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Old May 2nd, 2011, 01:45 PM   #28
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Re: Stage Mic Placement for avoiding Phase issues

Excellent questions all. As I mentioned, most of the students (especially in the Upper School) have no problem at all being heard in the back row when you're there live. It's a priority of the faculty to teach them to do so and does in fact explain their reluctance to add mics of any kind.

The arrangement of the auditorium varies by show. For the last show we did (the one I sent you the sample from) the four panels surrounding the word "STAGE" on the diagram -- front and center in that apron -- were removed and that was the pit. Often, the band/orchestra accompanying the musicals sits in the area that appears to be an aisle between cam 2 and the side wall, and may spill into those seats, which would be reserved for that purpose. (If that description isn't clear I can post another graphic).

The whole "perspective" issue is a "nice to have" but not a "need to have." All I've ever really been concerned about is getting the sounds of the performers, clearly and not like they're inside a tin can, to be heard over the instruments. And secondarily, to remove the room echo and boominess and of course minimize audience noise. I actually have no problem when our shots are in CU but you still get the whole-house sound, because the nature of the sound should not, in my mind, change with every cut and having a very close audio presence would sound weird in a wide shot. (Which is why I always UNcheck "Audio Follows Video" when doing the multi-cam edit. Which in retrospect doesn't matter because I never use the raw audio from the cams anyhow -- although they can be part of the mixdown.) As with images, I want the cleanest source material possible and I can always degrade it in post -- but as we've learned you really can't make it "better."

I do, in fact, have grave concerns about both cost and time, but I am willing to do what it takes without wasting either.

Really appreciate all the time, effort and thought you've put into this. It's way above and beyond. Not sure I would have the patience to stick with this for someone as cranky and opinionated as I am. Thanks again.

Edit: Here's a plan showing where an orchestra or band might be when doing Musicals. If the band extends into the seating area they might remove the seats or they might just build a platform extending the first band area over them. Obviously for full concerts they are all on the stage.
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Old May 2nd, 2011, 04:08 PM   #29
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Re: Stage Mic Placement for avoiding Phase issues

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Without any doubt whatsoever, the most effective microphone is a PCC, it used to be a Crown PC166. The same designer has produced an excellent replacement - and a data sheet is here: http://www.bartlettmics.com/TM-125C_datasheet-color.pdf
Are there samples of a small play or performance that was recorded entirely with the Bartlett TM-125? I'm curious to hear what it sounds like. I saw the sample of the truck running over the mic, and thought the sound of the mic was great close-up.
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