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Old February 7th, 2008, 07:18 PM   #16
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"Lavs on all three won't work because you only have two tracks of audio and putting two lavs on one track is a big problem.
Could you elaborate on this a bit? Is it a problem because you can't separate the voices or is there a technical reason that it won't sound good or is it something else? Thanks.
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Old February 7th, 2008, 08:38 PM   #17
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Could you elaborate on this a bit? Is it a problem because you can't separate the voices or is there a technical reason that it won't sound good or is it something else? Thanks.
I think he meant that putting three lavs on one track (1 for L, 1 for R) is hard without a mixer.

But along this same line, I assume that 3 lavs + a mixer (E44?) would be fine? You take the 3 lav lines, combine them into one track and output them XLR inputs on the camera. I assume this is a solution to my "can't have a mic guy" problem, isn't it?

3 lavs, one mixer, into one camera, job done... ?
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Old February 7th, 2008, 09:00 PM   #18
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Originally Posted by Lloyd Claycomb View Post
I think he meant that putting three lavs on one track (1 for L, 1 for R) is hard without a mixer.

But along this same line, I assume that 3 lavs + a mixer (E44?) would be fine? You take the 3 lav lines, combine them into one track and output them XLR inputs on the camera. I assume this is a solution to my "can't have a mic guy" problem, isn't it?

3 lavs, one mixer, into one camera, job done... ?

Not quite. The problem is a given speaker is being picked up by more than one microphone at a time. When the mics are fairly close together, the two signals have a very slight time delay between them, making them slightly out of phase with respect to each other. When you mix them to the same channel, you produce a phenomenon known as 'comb filtering' as the two waveforms combine with each other to selectively reinforce some frequencies while cancelling out others, leading to a very unnatural sounding result. It's the same sort of beat note thing you get when you hit two side-by-side keys on the piano at once. The rule of thumb is that when person 1 is speaking, any mic you combine with the signal coming off of the mic closest to that person must be at least three times farther away from them. So if the closest mic is 1 foot from the speaker's mouth, any mic whose signal you want to mix with it must be at least 3 feet away from the speaker. Then even though that takes care of the comb filtering issue, you still have to deal with the echo effect as the closest mic gets the speech first and then the second gets the same sound but with an audible delay. Mixing multiple lavs can be done but it's not a trivial exercise.
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Old February 7th, 2008, 10:00 PM   #19
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Not quite. The problem is a given speaker is being picked up by more than one microphone at a time. When the mics are fairly close together, the two signals have a very slight time delay between them, making them slightly out of phase with respect to each other. When you mix them to the same channel, you produce a phenomenon known as 'comb filtering' as the two waveforms combine with each other to selectively reinforce some frequencies while cancelling out others, leading to a very unnatural sounding result. It's the same sort of beat note thing you get when you hit two side-by-side keys on the piano at once. The rule of thumb is that when person 1 is speaking, any mic you combine with the signal coming off of the mic closest to that person must be at least three times farther away from them. So if the closest mic is 1 foot from the speaker's mouth, any mic whose signal you want to mix with it must be at least 3 feet away from the speaker. Then even though that takes care of the comb filtering issue, you still have to deal with the echo effect as the closest mic gets the speech first and then the second gets the same sound but with an audible delay. Mixing multiple lavs can be done but it's not a trivial exercise.
Hmm. I see what you mean. Then what about changing the set configuration slightly. Instead of the two kids sitting so close together, perhaps their sitting around a small coffee table with a good 3-4 between each other. Or maybe not a coffee table... whatever.... just get configure the layouts so that there is 3-4 feet between everyone... maybe they're on beanbags..... I can work on making it look right later, but I need to know the logistics if it is even going to work.

Three people, 3-4 feet apart, all on lavs (3) going through a mixer to one XLR camera input. Will this work better?
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Old February 7th, 2008, 10:02 PM   #20
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Here's what we did in TV news when you only had one camera man and one reporter. You stick with two mics. You put the wireless lav on your reader. You use your shoe mic for nat sounds like the kids reacting. It's the standard in the news industry when working with one camera and one reporter. If you really want the natsound mic always over the kids, then you can go wireless with that too and place it on a stand or suspend it over the location where you want to gather the sounds. If you really wanted try and have all three, you could do this.

1: wireless lav mic on subject
2: wireless suspended ambient mic over kids
3: natsot shoe mic that you switch out with the other two mics as needed (but that too is a pain because you will have to keep plugging in and unplugging.)

I say stick with the two mics, and remember the shoe mic is going to pick up the natsound that is in front of the camera, which is what you want.

I did this with a Canon XL2 because I wanted to run a natsound mic and a wireless at the same time, and record in 16bit.

It worked great. Though I have to admit I was going to split the tracks later, but never got around to figuring out how to do that in Permiere Pro. Make sure your editing program allows you to work with adjusting the levels in the different tracks, simpler programs don't do this. And it would be a waste of time to go through all the trouble of collecting the sound on different tracts, but never being able to edit them individually.

Good luck.

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Old February 7th, 2008, 10:14 PM   #21
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Originally Posted by Alfred Diaz View Post
Here's what we did in TV news when you only had one camera man and one reporter. You stick with two mics. You put the wireless lav on your reader. You use your shoe mic for nat sounds like the kids reacting. It's the standard in the news industry when working with one camera and one reporter. If you really want the natsound mic always over the kids, then you can go wireless with that too and place it on a stand or suspend it over the location where you want to gather the sounds. If you really wanted try and have all three, you could do this.
When you say shoe mic, would that be a hyper cardioid? Or are they different? What's a shoe mic?
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Old February 8th, 2008, 12:09 AM   #22
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a mic on camera is NOT what you want to use for this at all. it'll pick up way too much room tone and slap. a on camera mic is good for crowd noise and other general ambience, not for getting clean dialog.

take ONE lav, place it on one of the two kids on the inside of them. if they are close to being shoulder to shoulder, the one mic will pic up both of them ok. yes the further kid will be a little lower but it will be ok. maybe it will also be the louder kid who is further away. put the other lav on the reader. done.

next option, lav the reader, cardiod on boompole for the kids if it clears the shots. as others have said, two lavs too close will phase each other for sure when mixed together.
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Old February 8th, 2008, 02:47 AM   #23
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Sorry about the confusing terminology.
By shoe mic, I mean the standard natsound mic on the camera.

Steve Oakley is right about the natsound mic picking up every bump on the camera, but as a professional you learn how to shoot and move without bumping. In five years of ENG (electronic news gathering), I would estimate that bumping effected less than 5 percent of the clips. But I don't want to get into an arguement about the effectiveness of the camera mic. The fact is, if you are shooting in more of a studio like setting (even if it's your living room), and you aren't moving the camera around, you do need to find a way to pick up everybody's sound.

But before you consider buying more sound equipment, I have to ask, why in the world are you using just one camera? As I understand it, you are going to be rolling on this storytime from start finish. How in the world are you going to get the camera from the subject to the cute faces of the children? You can't do it professionally with just one camera. You will have to stage your cutaways after the main part of the shooting. And often they won't match. I've been there, done that, won't work (that well). What I suggest, and I missed what type of camera you are using, is that you pick up a second camera to use as a basic wide shot, or a constant shot on the reader. With the second camera, you now have a chance to capture that third track of sound, maybe even a fourth.

I don't know what the finished product will look like. Maybe you could share. But it seems to me you need two cameras, and then you will have your extra sound track.

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Old February 8th, 2008, 04:25 PM   #24
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There's really no way to boom this? Close as the subjects are to each other, I think a good boom op could cover it with a hypercardiod.
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Old February 8th, 2008, 05:03 PM   #25
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There's really no way to boom this? Close as the subjects are to each other, I think a good boom op could cover it with a hypercardiod.
Trouble is, Lloyd doesn't want to use a boom operator. While a fixed boom could cover either the storyteller or the kids, just one really can't cover both at once. Now TWO hypers on booms might do it ...

I still like the idea of a lav on the storyteller and a boomed hyper on the kids, aimed at the quieter speaking of the two.
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Old February 8th, 2008, 05:03 PM   #26
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But before you consider buying more sound equipment, I have to ask, why in the world are you using just one camera? As I understand it, you are going to be rolling on this storytime from start finish. How in the world are you going to get the camera from the subject to the cute faces of the children? You can't do it professionally with just one camera. You will have to stage your cutaways after the main part of the shooting. And often they won't match. I've been there, done that, won't work (that well). What I suggest, and I missed what type of camera you are using, is that you pick up a second camera to use as a basic wide shot, or a constant shot on the reader. With the second camera, you now have a chance to capture that third track of sound, maybe even a fourth.
Alfred
I'm actually using two cameras. I have one decent one and one so-so one. Cannon A1 and HV20. The A1 I have two tracks for audio via XLR, but I don't know how to get two on the HV20 since it's 1/8" line in. I wasn't really planning on using the HV20 to record the sound since it didn't have any XLRs in. I never really thought about it, but I suppose it could be done, right? 2 lines feeding into the A1 and one line into the HV20 and then I wouldn't need a mixer I guess, right?
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Old February 8th, 2008, 05:08 PM   #27
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Trouble is, Lloyd doesn't want to use a boom operator. While a fixed boom could cover either the storyteller or the kids, just one really can't cover both at once. Now TWO hypers on booms might do it ...

I still like the idea of a lav on the storyteller and a boomed hyper on the kids, aimed at the quieter speaking of the two.
I will post a picture of the proposed seating arrangements. I am with Steve that I think this is probably the best bet. Lav the adult who sits in the middle, and have the kids on two boom/hypers.
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Old February 8th, 2008, 05:15 PM   #28
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Originally Posted by Lloyd Claycomb View Post
I'm actually using two cameras. I have one decent one and one so-so one. Cannon A1 and HV20. The A1 I have two tracks for audio via XLR, but I don't know how to get two on the HV20 since it's 1/8" line in. I wasn't really planning on using the HV20 to record the sound since it didn't have any XLRs in. I never really thought about it, but I suppose it could be done, right? 2 lines feeding into the A1 and one line into the HV20 and then I wouldn't need a mixer I guess, right?
I think the HC20's external mic jack is accepts a stereo mic signal. If your mics have internal battery power, a Beachtek adapter or something like this Studio One unit http://trewaudio.com/store/product.p...&cat=31&page=1 would allow you to feed two XLR mics to your HV20 or you could probably just use a Y-cable such as this one http://trewaudio.com/store/product.p...&cat=31&page=1 ...
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Old February 8th, 2008, 05:17 PM   #29
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I will post a picture of the proposed seating arrangements. I am with Steve that I think this is probably the best bet. Lav the adult who sits in the middle, and have the kids on two boom/hypers.
Adult in the middle on a sofa?. I was thinking of the kids side by side facing the storyteller, shoot in reverses so you have the adult in MCU cutting with reaction shots of the kids. Your line of action is drawn from the storytellers eyes to the kids eyes. Are you going to shoot in one take or try for multiple takes?
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Old February 8th, 2008, 05:20 PM   #30
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I think the HC20's external mic jack is accepts a stereo mic signal. If your mics have internal battery power, a Beachtek adapter or something like this Studio One unit http://trewaudio.com/store/product.p...&cat=31&page=1 would allow you to feed two XLR mics to your HV20 or you could probably just use a Y-cable such as this one http://trewaudio.com/store/product.p...&cat=31&page=1 ...
Very nice! Thanks for those links. That seems ideal. Running two cameras would get me 4 audio tracks, of which I only need 3. So I see this working great.

Steve, for this situation, if I were to go with your suggestions, what hypers would you recommend me buying? I think the best setup till now has been what you suggested--adult one lav, each kid with separate boomed hyper.
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