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Adjul Gardner June 9th, 2014 01:17 PM

Most challenging recording environment
 
Hi,
I film wilderness immersion courses at the school I work/live at. I started editing videos last year of footage the program guides filmed themselves. Very monotonous, on-a-tripod-for-3-hours, stuff.

Now I'm getting to film it myself, and I'm wondering how I can better the audio. Last years stuff was psuedo-unusable.

My main concern is filming dialog, here's the situation I'm trying to work out:
-People are sitting in a circle (~12 people)
-There is oftentimes a fire in the middle (with crackling noise, and sending up smoke and heat)
-People talk softly sometimes
-Lav-mics are not not an option.
-I am a one man crew, and can't see handheld-booming as a possibility as I'll be juggling two cameras

What I've tried so far in the field:
-Using camera mic, boosting the hell out of it = lots of noise, still faint voice signal
-Putting a handheld digital recorder down on the ground in middle of the circle (next to fire) = much better audio, but fire is also still loud, not the best

Experiments I've done in my "lab":
-Getting a set of ME30w condensor mics on tripods, put on either side of the "fire" (my tablet with a fire recordeing, lol), aimed outwards = louder audio, but mics are omnidirectional, so louder fire as well

Stuff I've still got to try:
-Hanging a boom mic from a stationary boom pole on a tripod or attached to a tree, so it hangs within the circle, and out of the frame (not sure if this would work with also trying to get wide angle shot of the group)
-Getting a juicedlink for camera shotgun mic, enabling me to jack up mic levels without also increasing noise as much
-putting a Zoom H1 on the camera, hooked up to shotgun mic, to bypass cameras auto gain control and give better signal to noise ratio
-Find *directional* mics with cardioid polar pattern, to set on tripods/sticks in ground on either side of circle to feed into Zoom H1 (anybody know where to find these, I'm overwhelmed by the microphone product universe).

Everyone tells met his is impossible unless I lavalier people, or get a boom in there. I'd rather not have to worry about booming, but I can see it might be the way to go. I'm also on a tight budget. Whatever it is, I'd like to be able to do it with $300-400.

P.S. current camera is a Canon XA-10 with XLR inputs, a Rode VideoMic, with Juicedlink and Zoom H1 arriving tomorrow for testing. Prior recorder was an Olympus DS-50 (couldn't turn AGC off and no 1/4" tripod/camera mount, so I'm getting a Zoom H1)

Thanks
Adjul

Greg Miller June 9th, 2014 01:40 PM

Re: Most challenging recording environment
 
If the people are sitting in a circle around a live fire, you've got a tough job. You surely can't work a boom with a fire in the center of the circle.

Keeping voices louder than the noise (fire) is a function of having the mics closer to the people than to the fire. That means a lot of mics. If you don't want to use lavs, you might get away with mics on stands, but I would still guess that you'd need perhaps one mic for every two people (every three at the most).

Furthermore, you should record each mic on a separate audio track, so that when you do your final mix you have only one mic "open" at any given time. If you have six mics open, that will just give you six times as much noise from the fire.

The above means either recording onto a laptop with multi-track software, or else using six separate "pocket" recorders, and then trying to sync up all six tracks in post. Rather cumbersome, since the "pocket" recorders tend to have less than accurate timebase.

Even if you use a really cheap recorder, you won't make your $300 budget. A Zoom H1 costs around $100 each, so that's $600 to begin with. Add to that the cost of the mic stands, memory cards, etc.

You could buy a dozen Sansa Clips, and clip one on each person's shirt. That would cost perhaps $500 and you wouldn't need memory cards. But then you'd have twelve tracks to sync up, and I guarantee you the Clip's timebase drifts all over the place. It would be a mixdown nightmare. Furthermore, the resulting audio would not be as good as with the H1s.

Alternately, lose the fire, put everyone around a 6-foot table in a dead and quiet studio, and you might get away with one good boundary mic in the middle of the table. The key there is "no fire" and "quiet studio."

Adjul Gardner June 9th, 2014 02:36 PM

Re: Most challenging recording environment
 
Ah, the studio solution, why didn't I think of that.

Sansa clips sounds more doable than a bunch of lavs, $-wise and also not needing wires everywhere. Still probably too obtrusive, and downloading and organizing and syncing that would be hell.

I'm starting to think I need to just go with the clearest quality mic I can get and put it in either 1 spot, or split the channels into two mics and get some condensor mic-pair like this:

Behringer C-4 Stereo Matched Pair Single Diaphragm Condenser C-4

And put them on either side of the fire within the group. I'm not going to get the mic closer to the people than the fire, I'm not willing to put that many mics into action and keep track of all that technology. I just want to do the best I can with either 1 or 2 mics.

Would putting a mic overhead of the people/fire make it any better than on the ground? Why do people prefer to boom overhead?

So is AGC even an issue here? I guess I might want a recorder with AGC, because people can talk really soft and then suddenly it can get really loud and boisterous. Or at least like what the juicedlink has where you can record a backup track at -20db or whatever.

Greg Miller June 9th, 2014 02:55 PM

Re: Most challenging recording environment
 
How can you possibly hang a mic "within the circle" where it will not be subjected to the heat and smoke of the fire? If your goal is to destroy an expensive mic, I think you should try this.

There is no way you can "jack up" the voices, without also raising the noise of the fire by the same amount. Gain is gain, it equally affects everything that the mic picks up.

"The clearest quality mic" you can get will simply give you "the clearest quality" recording of the fire, as well as the voices. Your problem is not clarity, as you've described it the problem is noise from the fire. No mic can magically grab the voices and ignore the fire. Sound waves are sound waves. If noise from the fire is a problem, you need to get the mic(s) closer to the voices and farther from the fire. That should be obvious.

If you put a cardioid mic close enough to the people to pick up their voice louder than the fire, then the cardioid pattern will probably not be wide enough to pick up more than a few people really well. The fire in the middle of the circle prevents you from pulling the mic back where it could pick up five or six people. But if it was that far back, the voices would not be very clear, the mic would be too far away.

AGC will not solve the problem of the fire (and other background noise) being too loud relative to the voices. It may help with voices getting really loud, but if the AGC constantly changes the gain, you will clearly hear the sound level "pumping" up and down.

Adjul Gardner June 9th, 2014 03:22 PM

Re: Most challenging recording environment
 
Bluetooth microphones that go into people's ears...lol..?

Bryan Cantwell June 9th, 2014 04:30 PM

Re: Most challenging recording environment
 
1 Attachment(s)
Here's one possible solution (with handy illustration) for ya...

Get a Tascam DR-40 and TWO of each of the following:

Audio Technica AT875
Audio Technica AT8314 50' XLR cable
Audio Technica 8471 Isolation Clamp
Auray MS-5230 Mic Stand

Slap it all together, and shoot across your group from opposite sides, offset as seen in the attached professionally illustrated illustration. It's a bit over your budget, but it's one of the few setups that will work with your rather restrictive restrictions.

Adjul Gardner June 9th, 2014 05:36 PM

Re: Most challenging recording environment
 
Is that any better than some Zoom H1s/Tascams sitting spaced-out within the circle? Is the point that the downward-pointed boom mics would isolate the sound locally

I was thinking a set of two Zoom H1 on opposite sides wouldn't be too bad to download/maintain/and sync.

Thanks for taking the time to draw that, nice colors :)

My professional documentary friend who did footage at our school last year in these conditions told his stand-in shooters to either have people pass around a lav mic when they spoke, or to get inside the circle and get right up in people's faces with the cam/shotgun (although there goes my ability to know I'll always have my wide camera shot to use, if I'm right in the middle of it).

I was in the program he was taking, and the lav-mic passing wasn't great. Killed the spontaneity of what was happening a lot of the time. And people didn't do it 40% of the time and just talked.

Jay Massengill June 9th, 2014 07:11 PM

Re: Most challenging recording environment
 
If you have two two-channel sources of full 48V phantom power, such as two XA10 cameras or an XA10 and some combo of JuicedLink XLR preamp/H1-type recorder or mini-cam, or a full XLR audio recorder; then I would try to use four cardioid mics placed on low stands (12 to 18 inches high) inside the ring of people. The null of the cardioid mics would point toward the fire and each mic would cover three people. With the mics being as far from the fire as possible without being too close to the center person of each three-person set.

I would suggest AT2021 mics at $79 each. They have good sensivity and a good signal to noise ratio and are very inexpensive for how clean their noise floor is, but they do require full 48V phantom power.

It will still be a difficult situation in total, but at least you could get clean audio based on my past use of these mics. The built-in mics of most mini recorders are not directional enough to reduce the sound of the fire, plus being in a stereo configuration keeps the mics from being optimally positioned for your situation.

Plus the AT2021 mics are black. If you use all black cable connectors and very short stands placed strategically, when exposing for the faces or for the fire, the mics would probably be impossible to see at all if shooting at dusk or later.

Adjul Gardner June 9th, 2014 07:34 PM

Re: Most challenging recording environment
 
Thanks Jay, that seems like the best solution yet. Except-- our meetings run long and it sounds like that would suck serious power, whether from a field recorder or a camera. I wonder if there's something like the NTG-2 that runs on it's own power and also has XLR, if XLR is even necessary

Jonathan Levin June 10th, 2014 10:29 AM

Re: Most challenging recording environment
 
What about 2 mics that people pass around. 1 mic for six people, and another for the other six.

At least you could edit out the parts where there is the "passing". Or b-roll.

Not glamorous, just a thought.

Jonathan

Adjul Gardner June 10th, 2014 04:10 PM

Re: Most challenging recording environment
 
I won't go for passing the mic, it affects the environment and I want to capture spontaneous discussion. I've been in one of the programs where we were asked to pass a lav in our hands and it didn't really work.

Got the juicedlink today and H1, which I tested in different combinations.

Compared the H1 to the Olympus recorder I have, which has automatic AGC that I can't turn off. HUGE difference in recording quality. Did some sitting in a circle tests and realized that the AGC on the olympus was trying to make up for lack of signal in most of our recordings, unless the people speaking were directly in front of the recorder.

The juicedlink seems neat, but alls I found out really was I had my VideoMic input turned up too high and hence all the noise. I turned it down to ~50 and it was much better. The juicedlink had slightly less noise, but not work $200. I'll be trying the VideoMic with the VXLR I got plugged directly into the camera, and see how that works to change input level on the fly and watch the levels.

As for sitting-in-a-circle audio, here's what I think I'll do: get 3 Zooms total, and toss them spaced out in the circle to catch segements of 3-4 people, then keep the files organized and maybe even synced (or not, I can always put them on a timeline, PluralEyes them, then pick and choose which source I want). Getting them closer to the source (like everyone keeps telling me) as well as ditching the auto-gain should make the difference I need.

Adjul Gardner June 15th, 2014 12:16 PM

Re: Most challenging recording environment
 
I used Bryan's multi-mic solution with the 3 Zoom H1s I purchased. With big cheap (25$) windmuffs on them, I split our circle of sitting people into 3 sections, with a Zoom facing out from about 2 feet away into each section. Fire was in the middle, and the Zooms act directionally, so pickup was great, have 3 tracks to pick from or sync (not sure how that would work with phasing, but I only ever need one at a time).

Only issue was a couple of the Zooms being a little too close to the fire. Will keep them further out next time.

Tom Weistar June 24th, 2014 04:45 PM

Re: Most challenging recording environment
 
Looks like you came up with a solution with the H1s. That is what I was going to suggest. A couple points to consider; mount them horizontal knowing that the distinct left/right channels will have will have a better mic placement for certain people in the circle. Then in post check which channel has the stronger signal for a given speaker and delete the other channel.

A step up might be to use a left right splitter with a lav mic on each channel placed closer to the speaker/s. Then do the same separation of tracks in post.

Given this in in a wilderness setting I think you made the right choice, keep it light and keep it simple.

I get good results with these inexpensive lav mics and the H1 Omnidirectional Mono Microphone

Left right spliter Amazon.com: HOSA Stereo 3.5 mm Phone Male - Two Mono 1-Tip and 1-Ring 3.5MM Female - 6-Inch (Discontinued by Manufacturer): Electronics

I lead wilderness journeys with youth and we often do "audio journals", send the kids off with the recorder to record their experience. It is a little awkward at first, but when they get used to it amazing things come out of them!

Hope this helps.


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