Binaural/Stereo recording outdoors

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pat1

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I want to record outdoor sound/ambience, I came across the 'Mitra 3d pro' mic on Vincent Larofet's page- https://vimeo.com/27071919
I am not audio expert, but after a bit of research it seems that you could recreate this setup with correct placement of two mono mics, as seems to be the case here:
http://www.trackseventeen.com/mic_rigs.html
I'm not putting the mitra mic down, as it seems to be a quick solution for someone who knows little about sound like me,

Can anyone suggest a setup for this kind of mic array, or is it even necessary? - are there stereo mics that are good enough to create this kind of 'immersive' sound?

I was looking at the Rode NT4, would this be a good one to go for?


thanks for your help.
 
The thing about binaural recording is that it's pretty much only good for playback through headphones. The effect is lost on playback through speaker systems.

There are plenty of stereo recording arrays, both arranged using multiple mics and available in single housings, that are much better for sound beds for film and television. AB, XY, MS. Decca Tree is great, but it a bit clunky for sound bed recording (it's really great for chamber music, orchestras, and the like).

Most hand-held recorders have either AB or XY stereo arrays built-in. You can get MS (mid-side) mics like the Shure VP-88, or XY mics like the RØDE Stereo VideoMic and Stereo VideoMic Pro, or the RØDE NT-4, or the Audio Technica BP4025. You can also create your own XY using two cardioids, or your own MS using a cardioid and a Figure-8. MS requires a decoding matrix to extract the stereo image. Google them and you'll find all sorts of options.
 
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Just for clarification....when you see "3D" audio, it just means stereo, or sometimes "quad", which a few handheld recorders can do. For nature recordings, I prefer M/S recordings. It sounds the most natural to me. It is technically three channels if audio. I prefer to use a Schoeps M/S setup. The Shure VP88 is an ok mic, but has high self noise, so quiet nature stuff won't work on it. If you want a single M/S microphone, the Sanken CSS-5 is one of the best solutions that I have used.
 
Cheers for the replies - I read a bit about the setups you mentioned, but could you just clarify the difference in characteristics between XY and MS setups.
Is one associated with film production (MS?) more than the other?
Davefisk - Shoeps M/S setup sounds expensive, is this a kit / mic set?
Sanken CSS-5 is also probably a bit out of my price range.

I'm probably looking at something below $700, so some of the mics that Alex suggested would perhaps fit my budget, rode n-t4 etc , and also would you suggest using a recorder like the Zoom h4n/Tascam...?


thanks



 
Read the yellow sticky about audio recorders. That should at least give you an idea of what's what.

As for patterns and mics:

AB is a spaced pair, at least 3 feet apart. You can control the spread of the stereo image by adjusting the distance between mics. AB can use cardioid or omnidirectional patters. The mics typically aimed stright forward. The left mic (listener's perspective) is panned left and the right mic panned right.

XY takes two cardioid mic elements and criss-crosses them, with the elements basically right on top of each other. The stereo spread can be adjusted by adjusting the angles of the mics, but since they're aimed across each other the left mic is actually panned right and the right mic panned left. I prefer XY to AB for most applications.

MS (mid-side) aims a cardioid element straight forward, and places a bi-directionsl (aka Figure 8) element perpendicular to the cardioid. You have to matrix the signal out by sending the Figure 8 to two channels, panned left and right, and phase inverting the right channel. The cardioid remains panned to the center. A self-contained MS mic will likely have an internal matrix allowing for direct output of the decoded stereo image. Some field mixers also have two channels that can be linked to decode the MS matrix. The spread of the stereo image is controlled by adjusting the ration of mid to side signals in the mix.

There are other stereo setups (ORTF, NOS), but XY or MS are your best bets, and there are people who prefer both.
 
Well, for stereo sound effects recording, a lot of people go with M/S, some people go with XY. There is no industry standard. Schoeps is a microphone manufacturer that makes high end microphones, and getting an M/S setup from them is very expensive, but it's top of the line. You'd also need to get a good zeppelin package for it, and that's another chunk of change. That's all above your budget.

For stereo background recordings and nature stuff, I like to use a high end recorder...something like a Sound Devices. If you are going to use a Zoom recorder or Tascam recorder then I'd put a good mic pre in front of it and come line level into the recorder. The most critical thing when it comes to nature recordings is having really quiet microphones and really quiet mic pres.
 
The place to start is where you want to end. Sounds kind of zen...

But how you record depends on what you want the recordings for, so it's the first thing you need to know.

M/S used to be very popular with some film folks and disliked by a lot of others. It was a pain to decode and the sole advantages were you could collapse it down to mono with out artifacts and you could vary the perceived spread in post. The down side was you need special mics or a cumbersome combo and you needed a decoder box to get stereo out. When all transfers and processing was real time this was a big disadvantage.

Today it pretty much doesn't matter. You can get M/S mics in a bunch of price ranges. In fact almost all "cheap" stereo mics are M/S and decoded in the mic to stereo. You can process M/S to stereo very quickly so the only real drag is you can't listen in stereo with out some kind of converter.

But you can take X/Y and convert it to M/S and back so all the pluses of M/S are also available with X/Y. I was trained in film in places that didn't like M/S so that is my preference but it really doesn't make any difference.

As to the demo it's ??? not good. First off the "typical shotgun" mic is pointed up in the air. What is he trying to record, birds? And the sound you hear is not mono, or is panned so??? That part is just bogus marketing crap.

The mic itself sounds REALLY bright and brittle. I'm guessing a very small diaphragm omni electret pair.

And they are 180 degrees apart. So you will probably have some mono collapse issues. And it just didn't sound good.

All the demos they did were just stereo.

As others have mentioned there are a bunch of different ways to record stereo. The ones where you try to mimic a human head are great IF you are only going to listen on headphones and not going to do a lot of post work to them.

It really makes no sense for film sound FX collecting.
 
Thanks for that, it did seem like a bit of a marketing gimmick... So I suppose what I am after is just a decent stereo mic like the rode nt4, a recorder and a pre amp...

thanks for the help
 
what about ORTF for film? i kinda like it a little bit more than X/Y, for me it sounds a little bit more natural...actually as i never done any audio for film, how ambience beds are constructed for film? is it mono files panned or just stereo files are used(if we talking about final mix as stereo not surround)?

p.s. sorry for my not so good english :)
 
Coincidentally, there was a discussion of the Mitra gadget over on the DVinfo forum. I was underwhelmed by the demo video. Both the performance of the Mitra microphone and the method of demonstration. Comparing a binaural mic to a shotgun just seems silly. He could at least have compared the Mitra mic to the built-in stereo mics on the camcorder. At least make some attempt to convince me why I should consider buying/renting such a gadget.

I have several stereo microphones (in order of my preference) Sony ECM-MS5, Rode NT4, and Shure VP88. I have never felt the need for a binaural microphone, given the limited usefulness of the recordings in the Real World.
 
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