Hiding Lav Mic
 

After five days of hiding lavs on actors, and trying various approaches to minimizing rustling, I've pretty much settled into the following as best practice:

Wrap the microphone capsule with a bandaid, rolled around the barrell so the bandaid covers all edges but does not block the sound port on the end (Side-ported tram lav mics need not apply).

Then using one or two long pieces of bandage tape (not as stiff as gaffer tape and pulls off less hair), I loosely tape the bandaid-covered capsule to float in the middle between the person's breasts. The tape suspends the capsule forming sort of an isolation mount, and the bandaid blunts any collisions of the capsule into the body while moving. The key is to get it suspended so it's just off the skin, but also away from the shirt fabric.

This method works on men and women... with women I have them run and place the capsule and wire, whereas with men I just reach under their shirt to place it. The big surprise is how much room men have there... athletic buff guys have that part chiseled out, and guys who don't work out have big man-boobs with a nice big valley between. I've heard that some people have more space to hide a mic by their shoulders, but haven't seen it in the wild.

There was a thread in the past on hiding lavaliers and I don't want to rehash all the possibilities in this thread, but any comments are welcome.

Re: Hiding Lav Mic
 

Don't forget the Broadcast Loop.

BTW - was listening to this weekend's shoot and the sound was quite good considering the surroundings and amount of ambient noise we had to deal with. Good working with you Tom.

-Garrett

Re: Hiding Lav Mic
 

???

Deborah

Re: Hiding Lav Mic
 

The "Broadcast Loop" is a strain relief loop in the cable of a lav just below the capsule. The cable comes down from the mic head an inch or so, turns and loops up through the hinge at the other end of the clip, then loops over again and is clipped between the mic clip and the inner side of the shirt on the opposite side of the fabric from the mic head. If you just let the wire dangle straight down from the mic it will transmit every tiny vibration right into the mic capsule.

Re: Hiding Lav Mic
 

How do you prevent picking up a person's heartbeat with this method? When I tried it several years ago, I got a low frequency kathump...kathump...kathump... throughout the entire shoot which can't be heard through headphones, but comes out clearly in post.

Re: Hiding Lav Mic
 

If you've got too much heartbeat, it likely means that you've rigged the mic in such a way that it's element is obstructed so badly that you're applying way too much gain.

On a properly rigged mic, the signal to noise ratio should be such that any heartbeat will be so far under the signal floor that it won't be a problem

If you're faced with this after the fact because someone didn't notice and fix the problem in the field, a simple high pass filter should clean things up (unless, of course, the person speaking is James Earl Jones and their voice is down there close to the "heartbeat" part of the audio spectrum. ; )

Hope that helps.

Re: Hiding Lav Mic
 

Here is a link to more good advice on Lav mics....
Location Sound Corp.

Re: Hiding Lav Mic
 

I actually did some experimenting a month or so ago, tugging on mics while listening for rustling. I found that the broadcast loop wasn't really helpful and may even make things worse because on clips that don't have a groove to hold that loop, the tugging just causes more vibrations as the wire slides across the clip. The rubber boot where the cable enters the mic capsule seems better at absorbing wire tug noise.

I've never heard a heartbeat. In fact I can't remember ever hearing anyone's heartbeat even without a microphone unless my ear was on their skin, certainly not when they are talking in a normal voice. I would suspect gain issues.

Re: Hiding Lav Mic
 

If the loop was rubbing where it passe through the hinge end of the clip you didn't have the cable clamped at the mic capsule end of the clip. The mic is on the front of the shirt, pointed up. The loop goes down, looping over and up through the clip by the hinge, then loops over again this time under the shirt, and is clamped to the shirt by the alligator clip. Since the wire is clamped, a tug can't cause the loop to contract.

Re: Hiding Lav Mic
 

My experience is that if it's secured then yes that eliminates the sliding noise (although doesn't eliminate tugging noise). What's the point of having that loop if it's in the middle of two secured locations (wire goes out of microphone, loops through the hinged end of the clip, and then the wire is secured at the other end of the clip). It seems to me the loop is more of an aesthetic consideration then, since the secured location absorbs any tugs before they get to the loop.

Re: Hiding Lav Mic
 

If the loop isn't there, the tug gets transmitted directly to the mic capsule instead of the shirt and clip

Re: Hiding Lav Mic
 

But if the cable is clipped to the clip, then that clipped connection will transmit a tug through the clip itself, bypassing the loop.

Re: Hiding Lav Mic
 

Look, this argument is silly.

Those of us who have been doing this a long time do what we do because at some point we discovered that something wasn't working the way we wanted it to. So we changed stuff until it met our expectations and needs.

It doesn't matter AT ALL if you use a loop, a square knot, or personally superglue the cables to the talent's tie. The point is whether or not you solve YOUR problem in a fashion that works to YOUR satisfaction.

If you don't want to learn how other folks do it after their experimentation, fine. Or do it another way. Nobody really cares.

If you think you have an even 'better' way - great. Post it for people to try for themselves.

But to tell people that what they've been doing successfully for decades is somehow "wrong" is kinda insulting. It implies that they've been too dense for their entire careers to understand that they've never solved the real world problem they started doing the thing to solve in the first place.

The other approach is to consider that if something a lot of people are doing that satisfies the problem for them - and you're not getting the same results, it MIGHT just imply that you're implementing the practice improperly.

Or it might be that your equipment is different. Or that you haven't yet encountered the same problems that they have. Or haven't pushed the gain the same way they did - or a THOUSAND other variables.

The only real problem is the feeling that you have to somehow "educate" people that they're wrong to be satisfied with their knowledge. Respectfully, that's ego talking, not the genuine desire to help them learn.

Something to be careful about, IMO.

FWIW.

Re: Hiding Lav Mic
 

Yes, true. But a tug on the clip produces far less noise than a tug on the mic capsule itself.

Re: Hiding Lav Mic
 

Picture guys!

highly appreciated

Re: Hiding Lav Mic
 

Tom, thanks for these great tips. I use lavs for weddings and event videography and up to this point have not had to hide them. However we are starting to do some projects that will require we do so your thread is exactly what I have been looking for.

Re: Hiding Lav Mic
 

Here's a web picture of the loop... since the cable is secured on the right in the clip or jaw, the loop on the left can't absorb tugs.

http://www.dvinfo.net/forum/attachme...ic-fitting.jpg

Re: Hiding Lav Mic
 

It's not supposed to. Because the cable is secured to the clip (on the right side of your picture) vibrations traveling up the cable are damped at the clip and don't continue into the mic capsule. If the cable came straight off the capsule without being constrained, vibrations traveling up the cable would be transmitted directly to the capsule and to the mic's diaphragm

Re: Hiding Lav Mic
 

I think the problem is that we're actually discussing two separate things here.

Vibration damping
and
Strain relief.

Each is a separate issue.

Good mic technique like this addresses BOTH but if you're rigging a wired mic for a walking talent where someone might step on the cable, then a little loop like this isn't going to be much good. Conversely, if the issue is someone simply twisting their upper body for a moment, it's PERFECTLY useful.

And if the talent is in a fixed position chair, there's no vibration present anywhere along the the wire, then the loop isn't really required for vibration damping.

BUT...

The real issue is that these things pop up when you least expect them, so it's just smart and safe to learn to rig things properly as a matter of constant practice - even when there's no obvious need to do so. That way, if the problem conditions DO show up, you already have a practice in place that solves it before you ever notice it's even there!

THAT is the sweet spot.

Re: Hiding Lav Mic
 

Bill as usual you bring a useful new angle to the discussion: Strain relief. I think that the loops in the picture I posted or the strain relief loops tied with thread below the shirt might very well be useful for strain relief. If there's a strain from someone twisting their torso the pictured "broadcast loop" might very well save the clip from getting pulled (as the wire pulls out of the jaws of the clip), saving a sound guy from needing to straighten the microphone clip so it looks good on camera. Or if the microphone is hidden, strain relief loop(s) could keep it from getting pulled out of its ideal suspended-not-touching-anything position.

What I discovered in my tests however, is that while those loops are relieving strain, they are simultaneously transmitting vibration as the cable is being let out and rubbing against the clip or looped cable. So one has to make a judgement call about whether strain relief or vibration damping is more important in a particular application. Since I've had much more vibration/rustling issues than issues with mics needing to be repositioned, I prioritize vibration damping over strain relief.

Personally my approach is to avoid the loops and instead rely on slack in the cable under the shirt.

YMMV and I'm not trying to say that professionals who have been doing this longer than me are wrong for using strain relief loops if that works for them.

Re: Hiding Lav Mic
 

There is the RODE PinMic. It is designed in a way there is no visible wire at all.

RODE PinMic Miniature Omnidirectional Microphone | L.A. Color Online

Re: Hiding Lav Mic
 

I tried out the Pin Mic. While I'm sure it has it's uses, I found it wasn't the general-purpose solution to hiding the mic that I would have hoped for, and I sold it. It looks like a bug or stain on camera. And because it's attached through the clothing it's impossible to isolate the vibration/tugging of clothing noise as a person moves, like I suggest in the original post. On the bright side it's almost as quick to set up as a lav clip and I liked the sound so much (for the price) that I replaced it with a Rode Lavalier with the same sound. Horses for courses :-)

Re: Hiding Lav Mic
 

I am using it at weddings to mic the groom for the vows. It works very well for me. Not that it matters to see a clip mic but the PinMic is just awesome in hiding it from general's sight.

I don't see any vibration issue. The problem I have is once the mic cap popped out and I lost it. Good that I can get a replacement right away from Rode.

Re: Hiding Lav Mic
 

Okay, this may be old news to folks here, but after battling the challenges of lavs for several years, I came up with a technique we use whenever possible. I'm certain it's not original with me.

We have a specific situation -- most of the people we shoot video of are wearing ball caps. They also are active, so when they turn their heads, they go off-axis, and the sound varies.

A couple of years ago I started putting the lav mic onto the bill of the baseball cap. Works best if the bill of the cap is dark -- you never see the clip. You could use the "vampire" clip, so nothing shows on the top of the bill. Run the wire under the hat, over the hear, down the neck, into the shirt, and to the transmitter. I have found a couple of times that the cable was a bit short, but the Tram mics we use have long enough cables.

With the mic under the bill of the cap, it really helps with wind noise, and (of course) the mic maintains the same spacial relationship with the talent's mouth, so audio is consistent.

Just another tool to have in your tool box.

Re: Hiding Lav Mic
 

This is common in the UK - hiding the mic. under the peak of the cap. Very often the transmitter will be inside the cap itself.

Re: Hiding Lav Mic
 

To stretch a point, in a sense, it uses the bill of the cap as a mini-pressure-zone surface.

Re: Hiding Lav Mic
 

Note to self: tell directors to cast more characters with hats. Especially top hats. That is brilliant... the shadows under the brim probably hide it well.

If only we could just gaffer tape a microphone on someone's face. Actually I've been meaning to figure out a better way of getting an iphone headphone-cord microphone to stay near my mouth, and I just now put a roll of gaffer tape in my car for next time. Just as the feds are trying to ban all cell calls.

On another subject, I'd be curious to see links to any good tutorials on hiding a lav in talent's hair. It seems like since the 1980's most people don't have enough hair to hide the microphone anywhere but in the back of their heads, which I'm guessing would give worse sound than a mic under clothes on the chest.