Is there a way to rig two matching shotgun mics to record stereo?

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bryersen

Member
I’m shooting a doc that has a wide variety of b-roll – quiet nature to driving cars to dancing with loud music. I have two Neumann kmr81’s that record the most wonderful interviews.
Is there a way to rig them to record stereo sound?
Or just record two directions for layering in post?

Thanks!
 
"stereo"is kind of wiggly. You can set up really any two mics as a stereo pair. You will get arguments over "accuracy" but...

IF you are trying to document something for ? a museum or/ then go for "accuracy". I put it in quotes because microphones do not "hear" the same way humans do so "accuracy" is kind of a silly goal. And no two humans hear the same way. The reason is that you "hear" with your brain. Your ears only capture raw data. Your brain interprets the raw data and that is what you hear. The problem with "rules" about these kinds of things is that your brain has different experiences than mine so it will process the raw data differently than mine will. What you hear is also heavily influenced by other input. Rain and frying bacon sound pretty much identical. Which you hear depends on context.

The really short version is Yes you can use your mics to record stereo. I would probably aim them narrower than I would with hypers or cardioids. That gives you a narrower field but you don't have a hole in the middle. If it's just BG's then maybe go wide and you can always pan closer.

Generally speaking in films stereo or surround is created in post not recorded in production.
 
I use 416's often for Broadcast TV in 'stereo' set up.....
If you want to do a simple XY then cross the mics at the 'capsule' NOT the tip. The capsule can be seen if you hold them up to the light.
Its about 1/3 up from the XLR base.
If you want to do it this way then you can't use blimps, they need to have no or just small foam shields on them.

For sports OB's (outdoors) I will use them as part of a multi mic stereo setup. The 'base' is a stereo XY mic like the Rode NT4 or AKG C522 then the 2x 416's in blimps are placed about 1.5 > 2m apart (the width of a very big TV screen) facing very slightly outward... In the mix those 416's are panned 70/30 and 30/70.
In that setup you have a big 'wash' of the crowd and then some 'definition' with the 416's.
 
bryersen said:
I have two Neumann kmr81’s that record the most wonderful interviews.
Is there a way to rig them to record stereo sound?
Click to expand...

Stereo isn't what shotgun mics excel at. The design of a shotgun mic (interference tube) says that off-axis sound is noise that should be cancelled. The whole idea of stereo is that the entire stereo field (almost all of which is off-axis to at least one mic in the array) is signal and should be recorded. You see the conflict here?

If you were talking about a pair of hypers, then yes, there are stereo arrays that work well with hypers. As there are with cards. And sub-cards. And omnis. And even fig-8s. Shotguns? Not so much.

That said, there's nothing to stop you from trying. You might hit on a method that works, at least as well as you need. I suspect that you might get something by using XY (find where the capsule is in the mic [typically toward the back]) and cross the capsules themselves. Another method is to AB your shotguns, make them parallel to each other and pointing straight ahead. For this to work they have to be fairly widely spaced, on the order of .6 meter and up (maybe as wide as 1.5m? IDK, beware creating the feared "hole in the middle" as it gets too wide). This spaced shotguns array is used (so I'm told) at events like football games and records crowd sounds in a recognizable stereo. I suspect that any of the other normal arrays (NOS, ORTF, AB, etc.) will give you unacceptable comb filtering artifacts from the interference tubes, but you can try them if you want.
 
Thank you three, that was very helpful.
I can now ignore the other array patterns, and focus on XY and AB, unless I shift my budget and buy a stereo mic, which I might. I get it - these mics are shotguns that might be able to do it, but better used for directional flavor in the mix.
A more specific question –
My b-roll is wide angle contemplative shots where the atmosphere of the space is crucial. Some of the shots will be long – 40-80 seconds. I want to give the sound designer and mixer what they need because I believe sound is the emotional base in films. That is why I shoot interviews with the Neumanns. I also appreciate that location sound is unique, cheap to get and can be fun to play with (if it’s clean!).
The question is – to give the sound editor and mixer what they would love to have (and make it easier and more fun to do their job!), should I get a used Rode NT4 and Tascom recorder and use the Neumanns for directional flavor? I can sell them when this trip is over.
What would you do?
I’ve thought about a Rode NT4 a number of times. This upcoming trip will be a lot of shooting this b-roll, not just interviews.
Thanks for your opinions.
 
Have a look at the Sony M/S mic's as they are ideal for camera mounting and getting an easy compact stereo set-up.

They are end fire M/S mics inside but output an AB signal with a width control, the ECM MS-957 and MS-907 are my stereo mics of choice and give a good sound for low cost.
 
IronFilm said:
Wait..... what?

Why then have I got tens of thousands of dollars worth of location sound gear....
Click to expand...

I think he means you are there shooting so getting some sound at the same time is "cheap". Not a good way to phrase it but kind of correct.

However it is also kind of wrong. While I do like it when an FX recordist has done some recording from the unique location of the shoot, random tracks by non FX people are often not much use. Unless you do sound post you are really unlikely to record the right things in a way that is useful to post. It's not just about "clean" it's about getting the right recordings and listening. And ambience recording needs to be about three minutes long to get useful sections that are long enough to use. That is three minutes of standing still with out changing perspective. Try it with a watch and holding gear. And while doing that pay attention to the various things that make it a waste. That chain saw in the distance probably kills it and the jet you can hardly hear is also a killer. For other things you need to know how to break down the sounds you want to record the sounds you need. It's not rocket science but it's hard to do if you haven't ever done real post sound editing (20+ tracks of FX) because it's a weird way of listening. And then you need to edit and label the sounds. In post I have no idea what they are or where you recorded them unless you have named them in a way I can understand. The alternative is I listen to all of your full length recordings and edit and label them by what they sound like to me. Given the time restrictions on post sound (usually) it is just way faster for me to pull things from my library.

My general recommendation to people is grab some sounds on location if it's easy. Especially backgrounds of unique environments. Odds are that I will use them more for reference than as actual sounds, but that is still useful. OR have a dedicated FX recordist on the shoot who knows the kinds of sounds post will want. On a low budget film the best person for that job is usually the person who will be editing the sound.
 
IronFilm said:
Wait..... what?

Why then have I got tens of thousands of dollars worth of location sound gear....
Click to expand...

Okay, I am chuckling here. Yes, that was a poor choice of words. What I meant was that while I am on location, recording a little more sound is an inexpensive addition to the day. And I enjoy the listening for it.
It's just me doing this project, so no FX or editor recording. I did production and post sound on three USC grad films, which means I've had some practice, made mistakes and fixed them in some way. It doesn't make me a professional. I do appreciate "the weird way of listening" as Noiz2 called it. I will "grab some sounds on location if it's easy. Especially backgrounds of unique environments" and my room tones and general ambiances.
What do you think of the worth of getting a stereo mic and Tascom recorder for my wide-angle contemplative b-roll? I think it's worth it (especially when I'm way out into nature, way past the freeway hum), but have never recorded stereo sound, so not yet done the wonderful "weird listening" with stereo. What is the difference in the listening?
What do you all think?
And mic opinions - Rode NT4 or Gary's "the ECM MS-957 and MS-907 are my stereo mics of choice?"
Which Tascom 4 channel? Or other choice?
Thank you!
 
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bryersen said:
What do you think of the worth of getting a stereo mic and Tascom recorder for my wide-angle contemplative b-roll? I think it's worth it (especially when I'm way out into nature, way past the freeway hum), but have never recorded stereo sound...
Click to expand...

First suggestion is to read up on it. Stereo isn't obvious to most people. Not how it works, not how to record it, not how to play it back.

The "biggie" for me is that people viewing your picture are fine with camera motion, but they aren't with stereo sound field motion. It can leave people "sea sick" and running for the exits. Yet another reason to never mount a mic on-camera, and never boom dialog in stereo.

On the practical side, if you're doing this outdoors you'll need to put it all in a wind basket, and you'll need good performance in hot/cold, dry/humid, and clear/dusty environments. The need to put it all in a wind basket pushes you toward coincident techniques, particularly mid-side (M/S, or just MS), although there are wind baskets available for near coincident (ORTF, NOS), they are considerably heavier and more unwieldy. The need for all weather performance pushes you toward RF condensers like Sennheiser or Rode.

This is why, if you look at the sites that cater to people doing recordings of nature, you'll find so many people recording with Sennheiser MKH 30/40 combinations in MS, in Rycote wind baskets (they make a basket specifically for Sennheisers in MS).

You aren't the first person to want to do this. I recommend that you learn from the people who have already climbed the learning curves. Those guys who record nature sounds for a living do it the way they do for good reasons. Just sayin'...
 
This is your own low budget project, right? And your goal is not becoming a full time FX recordist, correct?

If those are correct then I would not spring for stereo mic but instead get a Tascam DR-40. It's cheaper than a cheap decent stereo mic and sounds very good. Plus it's easy to pack and pull out whenever you find something to record. It's what I pack if I'm not hauling the full kit around.
 
I use a DR-40 to quickly record music gigs. The internal mics are decent and have a 90 & 120 degree width option. The XLR and 1/4" TRS/TS combo inputs are mic/line via a hardware switch, line being +4dB nominal to interface with pro consoles. There's also an adjustable delay on the external input to help time-align the int./ext.mics.. (approx 1.1 foot = 1 ms). It can also run on a standard phone charger/battery with a standard USB (A) using the included cable or three internal AA batteries. The USB also serves as an computer interface to the recorder's SD card. What's not to like?
 
JPNola said:
Because a top of the line Sound package is still far less expensive than a top of the line Camera package. :laugh:
Click to expand...

Not a relevant comparison. Most people on this forum don't run around with an ARRI and anamorphic set of primes etc etc

And even those who do, it will usually be rented in, not owned personally (unlike most sound gear, when we own all or at least most of it ourselves).

It is the norm for me to show up to shoots bringing more sound gear that I personally own than is the case with the camera department.
 
Thank you, Bruce, Noiz2, and Rick R. After your last comments, I went looking around at prices, DIY stereo set-ups/testing and some general learning. I also thought through my presumptions.
Yes, this is my own lower budget project.
My budget for improving my sound equipment is $650.
I had presumed that getting better production sound for my b-roll meant getting stereo sound. Now, I am thinking is to spend the money on a very good recorder and use it with my two Neumann shotgun mics. This would improve every sound I record. Yes, I would experiment with recording stereo with the two Neumanns (thank you all for your ideas, OzGizmo too, and I will enjoy the experimenting), but regardless I would get much better-quality sound than trying to buy both a stereo mic and recorder. Always, I would record mono ambiance and unique location sounds and sometimes also experiment with setting up the two mics in AB or XY stereo. I think that will bring the best quality to post.
The decision came down to this -- when listening to the recorded clips offered online, every time the noise floor was low, I was emotionally pulled into the sound.

Two remaining things for your opinions –
I’m looking at the Sound Devices MixPre-3 recorder for the quality of the preamps. It also is small and has a basic mode before I learn the advanced mode. It doesn’t have timecode generation, but that will get me to take better notes! Opinions?
One presumption to check out with you all – I presume that the quality of the preamp in a $650 recorder will be better than my camera – Canon C100 MkII. Should I use the MixPre-3 while filming interviews as well?
Any other advice?
Thank you!
 
bryersen said:
I had presumed that getting better production sound for my b-roll meant getting stereo sound. Now, I am thinking is to spend the money on a very good recorder and use it with my two Neumann shotgun mics. This would improve every sound I record.
Click to expand...

You are correct that it is incorrect to assume "better sound = recording in stereo".

I'm a professional sound recordist yet it is rarer than hens teeth I'd ever be recording with a stereo mic for production.


bryersen said:
Two remaining things for your opinions –
I’m looking at the Sound Devices MixPre-3 recorder for the quality of the preamps. It also is small and has a basic mode before I learn the advanced mode. It doesn’t have timecode generation, but that will get me to take better notes! Opinions?
Click to expand...

My top suggestion is the Zoom F4, it is only US$450 and is more capable than the MixPre3, and the F4 has itself excellent quality pre amps for its price.

http://ironfilm.co.nz/which-sound-r...various-indie-priced-sound-recorders-in-2017/
 
Thank you Ironfilm. And I read your blogpost - straight forward and lays it out as a friend would. Thanks.
Anyone else want to chime in?
 
I use the mixpre 3 when I don't have the room to haul around the 688. It is pretty good for doc shoots. The limiters automatically make it better than the C100 mic preamps. I have no real complaints, but I wouldn't want to use it on the majority of my shoots. I wish it allowed the creation of sound reports. I used a Zoom F4 once and it was fine and had a few more features for general audio capture than the Mixpre 3.

I have gotten in the habit of using a MixPre D to feed my camera for interviews. Nice big LED's, knobs, and limiters that are not attached to the camera.
 
cpreston said:
I have gotten in the habit of using a MixPre D to feed my camera for interviews. Nice big LED's, knobs, and limiters that are not attached to the camera.
Click to expand...

I do this myself. Not to a C100, but the idea is the same. And MixPre-Ds are one of the great bargains used, well below your budget. They give you most of what the MixPre-3s do, except for recording, and they are more flexible than the 3s when feeding to camera (because of course, that's what they are designed for). The MixPre-Ds have better micpres than any camera I've run across, much better metering, and outstanding limiters. If not the biggest bargain in all of sound, it's certainly in the top 5.

All of that, and you avoid most of the possible sync issues in post too. What's not to like? And no, you can't have mine. ;-)
 
Thanks CPreston and Bruce, but now am not clear. Won't the MixPre-3 and the Zoom F4 feed to the camera?
I also looked at the MixPre-D and see the value, but I'm looking for a mixer/recorder. I want to be able to wander after shooting b-roll and capture sound free from the camera.
 
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