May 20, 2017 at 8:46PM

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Mic+recorder for surround (post)purpose

Hi everyone,

I’m going to start with a new theatre-oriented documentary for school (and perhaps for a competition).
Up to now I’ve made video-oriented stuff, and a good stereo-audio was more than sufficient. But my last work was recently shown in a theatre as DCP and I heard the lack of a more complex audio track.
So, for my next work I’ll try to build a 5.1 audio track.
Anyway there are 2 conditions:
1. I’m a one-man crew, so I’d need to use an effective form factor audio recorder mounted on my camera;
2. The kind of sounds I need to capture are ambient sounds (then no interview set) like audio in nature documentaries.

So, please, I need your advices as experienced cinematographers.

I tried to figure out what to buy:
First of all I thought to avoid a camera-connected microphone, for the simple reason that camera’s pre-amps are not so good and add noise. So I thought to go for an external recorder, and specifically for a recorder with built-in mic (avoiding having cables that can produce noise if inadvertently touched buy the operator).

REAL SURROUND RECORDER
The first option seems to be Zoom H2n (https://www.bhphotovideo.com/c/product/811053-REG/Zoom_ZH2N_H2n_Handy_Re...): this tiny recorder gives a true surround 4-channels audio thanks to 3 front capsules and 2 rear capsules. It seems great but I have 2 doubts here: 1. the little capsules are not "deep" like a shotgun, so I’m afraid they can capture only a near sound field (and perhaps also the noise of camera or operator’s steps); 2. having the recorder mounted on the camera, the 2 rear capsules will capture the noise from the operator actions!

FAKE SURROUND FROM STEREO
Since what I wrote above, I thought another solution could be buying a stereo recorder instead, to have at least 2 varied channels from which I could build a fake surround in post. Stereo recorders with integrated mics are:
1. Sony PCM-D100 (https://www.bhphotovideo.com/c/product/1008089-REG/sony_pcm_d100_portabl...): the pros are S/N ratio up to 100dB and the variable angle of the mics’ capsules from 90° to 120°;
2. Tascam DR-100mkIII (https://www.bhphotovideo.com/c/product/1263849-REG/tascam_dr_100mkiii_li...): the pro is S/N ratio of 109dB thanks to the AKM AK4558 converters, but mics’ capsules are fixed in parallel position;
I’m wondering if these products can record a deeper sound-DoF than the Zoom H2n?
If I’d go for one of this stereo recorders, I should process the 2 channels to obtain a fake 5.1 in post.

MISSION IMPOSSIBLE: FROM SHOTGUN MONO TO FAKE SURROUND
Many videographers use shotgun mics for their cameras, so I found 2 models with integrated recorders:
1. Tascam DR-10SG (https://www.bhphotovideo.com/c/product/1257804-REG/tascam_dr_10sg_camera...);
2. Shure VP83F LensHopper (https://www.bhphotovideo.com/c/product/966010-REG/shure_vp83f_condenser_...) that declares a S/N ratio of 78dB (a bit poor in comparison with the stereo recorders above). Here the doubts are: 1. a bit noisy mics; 2. do you think is it possible to build a fake 5.1 in post starting from the shotgun mono recording? I suppose not, but I prefer to wait your advices.

Now, please, tell me which solution do you recommend for my purpose?

Thanks for your help.

4 Comments

I will share two things I've learned about surround sound. The first is that if you want a true surround field, you really need to worry about phase coherence, which means a highly centralized and regular 5-mic setup. The ZOOM is an inexpensive way to get there. Specialized pro solutions from DPA or Holophone are much, much more expensive. But they give you a good surround image, just as a proper stereo mic setup can give you a good stereo image.

The other thing I've learned is that you can create fake surround in many, many ways. The 5.1 sound field is your canvas, and you get to choose how you apply your brushstrokes to it. Generally, I've see music fed only to L-R, dialog mostly C, and effects distributed around Ls L R and Rs as appropriate. In this scenario you can use whatever mics you want to pick up whatever interesting sounds you want and then place them into your sound field. And don't forget the benefit of using a tasteful amount of reverb coming from the opposite end of the sound field.

Because surround speakers are out of view for any flat-screen projected image, you never need to worry about capturing those sounds with accompanying video. If there are birds and bugs doing things behind you, you cannot see them. You may need to capture their sound before they appear on screen, but you don't need to worry about the camera until they are in view. Therefore, I strongly recommend collecting your ambient sounds without a camera at all, and then blending them in during the post production process.

May 21, 2017 at 9:52AM

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Thank you SO much for your very useful reply and for sharing your experience.
Just I thing I don't understand very well: what do you exactly mean with "reverb coming from the opposite end of the sound field"?
Thanks again.

Adriano Castaldini

May 21, 2017 at 10:27AM

If you have source coming from L, you might hear a diffused/verby echo of that sound coming from Rs and Ls. If you have a source coming from Ls, you might hear diffused echoes coming from R + L. It takes some experimentation to get a surround system to behave both the way you want it to and the way you expect it to.

Michael Tiemann

May 22, 2017 at 6:22AM

Sorry for the very basic question, Mr. Tiemann, but which is the method to send into a track the efx-only of another track? Let's say I have L with a sound, and I want to send the reverb-only of that sound into Ls. Which is the right method? Using a Bus?
Thanks a lot for your help.

Adriano Castaldini

May 22, 2017 at 8:26PM

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