Omni Lav Phase Issues (?)

R

ralphabeel

New member
Hello,

I'm an up and coming sound mixer/boom op who operates 3 different mics (1 boom/2 lavs) through a 4 channel recorder (SD 442) into, for the most part, a two channel recorder (h4n).

One thing that's been concerning me when I want to run all of mics: If I mix the boom to the L channel, but then send both omni lavs to the R channel, will the two omni lavs cause phasing issues if the actors are close too each other?


Ideally I'd like to get a multi-track recorder, but only want to invest the money if the recorder has time code capabilities. Therefore I am left to my Zoom H4 until I can earn some more money. While the Zoom can record 4-tracks, the 3rd input is only a 3.5mm mini jack, which I don't always trust. I also would only want to record the 3 iso's if I could also do a Stereo/Mono mix, which isn't capable on the h4.

So, for now, what would you guys suggest is the best technique? I like having the split tracks for more post flexibility, but am also very nervous that my lav track will have audible phasing issues.

Any advice would be greatly appreciated!!!


Thanks,
Ralph
 
Hi, Ralph.

Your setup is nothing uncommon, especially for small (independent) films, ENG, and EFP.

ralphabeel said:
I'm an up and coming sound mixer/boom op who operates 3 different mics (1 boom/2 lavs) through a 4 channel recorder (SD 442) into, for the most part, a two channel recorder (h4n).
Click to expand...

The SD 442 is a mixer, not a recorder.

Anyway, whenever you have two mics summed to a single record channel, there is a danger of phase cancellation if the mics are close enough to each other. To compensate, you must actively mix levels between the two in order to constantly favor the mic that is active at any given moment. It only takes a slight level adjustment to make a huge difference. This can be pretty challenging when you're booming at the same time, so... grow a third arm? Or sacrifice the boom for the lavs, or the lavs for the boom. It's not really as big of a challenge when you have a two-person sound crew (mixer and boom op), but since you're a one-man-band, it's not that easy.

Really, without a way to multi-track, there's no ideal solution with your gear. Even with the limited capabilities of the H4n, while you could rig a 4-track recording, you're still going to have monitoring challenges without a quick way to monitor individual inputs. Theoretically, you could send the lavs to the main mix and use the Tape Out of the 442 to the 1/8" input (with a padded line>mic cable), then use the Direct Out of the boom from the mixer to send to an XLR input on the recorder. But still, it's a workaround and far from ideal.
 
Thanks for the speedy reply! My mistake calling my 442 a recorder...I was just typing faster than I was thinking :). Your setup is very insightful and not something I thought to try, so thank you!! I guess the only downside is that the lav signals would be unbalanced, but it'd only be going a short distance from the Tape Out of the 442 to my H4N 3.5mm in... little room for interference and therefore not so much of an issue...right?

Ideally I'd try the two Lavs to one side / boom to the other first and only resort to your setup if I am getting phase issues. Although I can image that a post sound mixer would prefer to have each source iso'd to its own track. Luckily I'm only doing small scale projects right now so they aren't too demanding. I usually try to just boom and only resort to the lavs if I absolutely have to.


Thanks again!
 
ralphabeel said:
I usually try to just boom and only resort to the lavs if I absolutely have to.
Click to expand...

And this is the best way to go, honestly.

When you're working with a boom and two lavs:
- For narrative work, boom first and use lavs only when absolutely necessary.
- For Documentary, lav the principle (when applicable) and boom the rest (split channel recording, of course).
- For news magazine, often lavs will be more useful than a boom, but not always. This can also work the same as documentary.
- And for seated interviews in any situation, with a single subject, boom on Ch1 and lav on Ch2 is perfectly reasonable. For two subjects, two lavs.

I used to do a ton of lifestyle programming for a cable network, and one show in particular often visited people in their homes. I had a 3-channel mixer (Shure FP33), a 416 with boom and zepplin, and three Lectrosonics radio systems in my company-issued kit. We recorded straight to camera (DigiBeta), and if the interview included the host and two homeowners I would pan the host left and the homeowners right, all on wireless. I'd mix between the two homeowners to avoid phasing. That gave the audio post mixer at least some control over the mix in post. You just have to figure out which source is most important on its own, and which others can be mixed without sacrificing too much.
 
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Can't thank you enough Alex! I'm kind of learning this on my own and don't have anyone I can go to with questions, so I really appreciate the advice you've given me here (especially the promptness of it!).
 
I had same situation, but with 3 lavs. Here there were 2 kinda "leading people" and 1 "gust".... So I putted the guest one side and the 2 others the other side.
And then it was a bit mixing, looking who was going to talk. And if there was mistake: "héé, we should do that line again"...

At the end there were 4 lavs.... But it went very well actually.
 
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