Problem recording two lavalier mics in close proximity - Help!

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Problem recording two lavalier mics in close proximity - Help!

Post by rightmindedness »

I'm having a serious audio recording problem using two Sennheiser MKE 2 lavalier mics in close proximity. Here's the situation. My wife and I are recording a live video broadcast. We sit directly next to each other facing a video camera. There's only about 6 inches between our chairs. I speak very loudly. She speaks very quietly. Both mics are going into a Mackie Onyx mixer. My mic is going into input 1 (track 1). Her mic is going into input 2 (track 2). I'm recording both tracks using Apple Logic Pro.

My voice is so loud that her microphone picks it up quite loudly. Her soft voice is picked up by my microphone but not very much. When I listen to both tracks combined, my voice sounds horrible. When I listen to my voice only on Track 1, it sounds fine. It's too difficult and time-consuming to go through our entire three-hour video broadcast afterwards and somehow cut out or mute each other's voices from our individual tracks. You can hear what each of our recordings sound like using the links below:

My mic soloed on Track 1 - http://www.thevoiceforlove.com/mics/Me%20-%20Track%201.wav
My mic on Track 1 and Track 2 - http://www.thevoiceforlove.com/mics/Me%20-%20Track%201&2.wav
Her mic soloed on Track 2 - http://www.thevoiceforlove.com/mics/Wife%20-%20Track%202.wav
Her mic on both Track 1 and Track 2 - http://www.thevoiceforlove.com/mics/Wife%20-%20Track%201&2.wav

These tracks have not been edited at all. Besides getting myself to talk more quietly, does anybody have any suggestions on what I could do to solve this problem with my voice sounding horrible? Without training myself to talk more quietly, what could I do so that each of our voices sound better, mind especially? Is there anything I can do so that neither of our voices are picked up by the other person's mic? Is there any piece of hardware I could purchase to solve this problem? I would really appreciate anyone's help. Thank you very much.
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Re: Problem recording two lavalier mics in close proximity - Help!

Post by Mike Stranks »

Bearing in mind you're on camera I think your options are limited. After a quick think I believe there are two options:

* You (personally) learn to speak more quietly and conversationally.
* You abandon the lavaliers and go for a different technique - eg one mic (and thus one channel) with the mic closer to her than you. An omni would probably be best to mitigate off-axis issues.

Of these two, the former is, I think, to be preferred. You need to aim for both voices being of the same style/"intensity" and adopting a more conversational style will make for a more effective video too.

HTH.
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Re: Problem recording two lavalier mics in close proximity - Help!

Post by Jonesd90 »

I haven't listened to the clips themselves so this might be less help but maybe you could play around with some sort of gate on her mic. It might be very awkward but perhaps worth a go.

Dave
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Re: Problem recording two lavalier mics in close proximity - Help!

Post by Hugh Robjohns »

rightmindedness wrote:It's too difficult and time-consuming to go through our entire three-hour video broadcast afterwards and somehow cut out or mute each other's voices from our individual tracks..... Besides getting myself to talk more quietly, does anybody have any suggestions on what I could do to solve this problem .... Without training myself to talk more quietly, what could I do so that each of our voices sound better, mind especially? Is there anything I can do so that neither of our voices are picked up by the other person's mic? Is there any piece of hardware I could purchase to solve this problem? I would really appreciate anyone's help.

This is a very common and inevitable problem.

The obvious answer that most people will give is that you train yourself to talk at a lower and more balanced level, and/or you ask your wife to speak up to balance closer to your level.

This won't cure the problem... in fact it will make it worse. At the moment your wife's voice sounds fine because it is really only picked up on the one mic, your's sounds horrid because it is picked up on two with a significant time difference resulting in strong colouration.

If you both talk at a similar level then both mics will hear the other source at a similar level and both voices will sound coloured!

One solution, as practiced in broadcast circles for the last fifty years, is to have someone actively and intelligently control the mix, fading one mic up and the other down (only by a few dB -- not fully on and off) to minimise the colouration.

Obviously, if you record each mic to its own channel, then you could also do this in post-production as part of the editing process (assuming you have one).... although you say this is too difficult and troublesome for you to be bothered with.

Frustratingly, quality requires at least some effort...

There are automated microphone switchers on the market (such as Shure's intellimix series and similar units from Audio Technica, amongst others) that can perform a similar job, but these are relatively expensive and take skill and care to set up so that they work as intended... and I'm not convinced this would be the best solution for you.

You could also do a similar thing in post-production using carefully set up noise gate plug-ins and side-chain linking... but again, probably not the solution that would suit you.

Fortunately, though, there is a far simpler solution that has all the immediacy and simplicity that you seek.

Invest in a tall, heavy stand with a long boom arm. Set it up to the side of the chairs just out of shot (possibly moving it closer to the camera to assist in keeping it out of view. Place the boom arm above the top of the shot so that it can support a microphone (a wide or standard cardioid, ideally) just above the top edge of the camera frame.

Point the mic down towards the floor. You might find, as was suggested above, that offsetting the mic from the centre so that it is closer to your wife might help to provide better level balance between the two voices. And a carpet on the floor will minimise strong HF reflections off the floor, further improving the quality.

Record the interview as before. No need to mix or rebalance anything. Job done. The judicious application of a compressor might help if your voice is still wildly louder than your wife's, but I doubt it would be necessary if you bias the mic to your wife's side adequately.

Depending on the mic's polar pattern, as you bias it towards your wife's side you might find that rotating it slightly so that both voices are equally off-axis helps to balance the sound quality. (In other words, point it back towards your shoes, rather than straight down!)

With this miking arrangement, trying to train yourself to talk quieter, and/or your wife to talk louder, would help significantly with the level balance -- but without increased colouration.

This kind of technique is used widely in TV location interviews and works very well indeed -- although you might also find hanging some duvets or other absorpent materials help if the room is a little lively. You also need to take some care over the boom position to avoid lighting shadows across the in-vision people.

Hope that helps.

hugh
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Re: Problem recording two lavalier mics in close proximity - Help!

Post by rightmindedness »

Thank you to everyone for replying. I appreciate it. I think I'm taking away two things. First, I really do need to talk more normally and not be yelling so loudly when I speak. Secondly, I think I'm realizing the difference between an omnidirectional mic and a shotgun mic.

You see, my original solution was to use shotgun microphones. I already had a Rode ntg-3 shotgun mic that sound great for one person recording, so I bought another one and did exactly as he suggested, I put both just out of frame above my wife and I. But I still have the same problem. Trying to solve the problem, I ended up buying the lavaliers thinking that they would do the trick. But they didn't. I did try to hang just one Rode ntg-3 right between both of us, but it didn't sound good. Now that I realize it, I guess it didn't sound good because it wasn't omnidirectional.

So, if I were to purchase a really great omnidirectional mic and hang it just right a little bit closer to my wife and me, it sounds like problem could be solved. Is that what I'm hearing? Also, I do have sound absorbing blankets all over my walls and I do have carpeting, so the room is in pretty good shape. If I were to get an omnidirectional mic, what would be a high-end solution for me to purchase?

Thank you very much everyone!
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Re: Problem recording two lavalier mics in close proximity - Help!

Post by Hugh Robjohns »

rightmindedness wrote:First, I really do need to talk more normally and not be yelling so loudly when I speak.

Probably a good idea ;)

my original solution was to use shotgun microphones....But I still have the same problem.

You would. The issue is about picking up the same sound on two mics with a small distance between them (resulting in a time delay between the two signals). The polar pattern of the mic would only help if it was (a) really pointy and (b)angled really carefully to minimise picking up the unwanted source and achieve a lot of recjtion (ie more than 12-15dB).

It can be done, but not if one person's voice is substantially louder than anothers.

Trying to solve the problem, I ended up buying the lavaliers thinking that they would do the trick. But they didn't.

No, they wouldn't. Although lavalier mics can be placed much closer to the sources than shotguns, you would still have suffered a lot of unbalanced spill from the louder voice to the more distant mic, and that's the problem.

I did try to hang just one Rode ntg-3 right between both of us, but it didn't sound good.

No, it wouldn't, because it is a bit too pointy for that application, and its off-axis pickup is inherently very coloured. Both voices would have been too far off axis and it would have sounded rather poor.

That's why I suggested a wide cardioid or a cardioid. An omni would work too (eg, haning one of your lavalier mics), but a cardioid would help to reduce the amount of room sound compared to an omni.

if I were to purchase a really great omnidirectional mic and hang it just right a little bit closer to my wife and me, it sounds like problem could be solved.

Save your money -- try one of the lavalier mics first. It might be a little noisy, and it might sound a little roomy... but it might be entirely adequate for your purposes too, so try it first.

If it is too noisy or too roomy sounding or you, then a decent cardioid would be the way to go, rather than an expensive omni. The Rode NT5 is a decent quality mic that would work well for not too much outlay.

hugh
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Re: Problem recording two lavalier mics in close proximity - Help!

Post by rightmindedness »

thank you, Hugh! I really appreciate all of your input. Very helpful. I wish I would have asked these questions before buying the two lavaliers. Oh well. Live and learn! Thank you.
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