Saturday, May 28, 2011

Mic Bags Revisited

So the theater's collection of mic bags were falling apart, and weren't built right in the first place, and then I go into a hectic series of rehearsals where I'm trying to get a dozen chattering tweens into microphones and out on to the stage.... and messing around with the old bags is really slowing things down.

So I made a quick trip to a local sewing store, set up a little sewing table by the sound board, and during rehearsal I ran off some newer bags. And this time I recorded some of the process.

This wasn't the perfect fabric, but it worked. It's some sort of medium-weight cotton-poly blend. It stretches a little -- mostly on the bias -- and doesn't trap quite as much water as cotton, but it could have been more waterproof. Ah, well; that's what condoms are for.

The first step was folding over the fabric, hitting it with the iron (a trick you learn early!) and pinning it so it doesn't slip while I mark out the outline of the pack with blue chalk. There's about three quarters of an inch margin here on the sides, and the top is about two inches here.

Next step is to cut out the individual little bags. Notice I've pinned each in the center.

So now I've done the same ironing trick to those top hems, taking them down to give me about an inch to close the top of the bag, and I've pinned strips of 1/2" velcro to them.

The first trial pack, I ran the velcro full-length, but because velcro doesn't stretch it proved too difficult to get the microphone into the bag. So this works better; there's about a quarter inch space on either side when the bag is finished.

Now we get to play with machines. I had some crazy computerized home sewing machine available which really, really made me miss my old Bernina Industrial. But it did the job. Here I'm stitching the entire length of the top hem about 1/8" in, and down the length of the velcro. After pulling the pin I turn back and go entirely around the velcro and lock off the stitch there. There's no need to lock the start because that will be under a seam.

Pin again and stitch down the sides. Remember I had 3/4" margin? I'm splitting it here for 3/8" between mic pack and stitches. With the slightly stretchy fabric that worked out almost perfectly. You may need to experiment with yours to find the optimum measurements.

(I did one bag, tore it apart with seam ripper and re-did it, and only then did I start assembly-lining the eventual twelve bags I built this time around.)

The Elastic I used for most of these was recycled from the old bags. I eventually used some lighter-weight 1 1/2" I bought myself, measuring the first one right on one of my actors. For the elastic I made, I turned over the top a quarter inch and stitched the velcro over that. The cute home sewing machine with all the computerized stitches didn't have a manual, and it wasn't a proper serger anyhow. Same excuse for why everything is straight stitched, without any zig-zags...I could get the machine to make an outline of a fish on the fabric, but the ordinary zig-zag was hidden somewhere deep in its tiny electronic brain.

The mic packs are Sennheisers, and fairly short, plus the bags are just a little long. This is the position I needed to stitch it in to get it to sit with the center of gravity slightly below the centerline of the belt. Oh, and after making a half-dozen I finally realized it was easier to put them on the actor if you put the female velcro out!

And now we get old-fashioned. The simplest way to attach these is by hand-stitching. The key stitches are the four do them just like a buttonhole.

If you have the skill and patience, (and happen to be sitting at a sound board over a long rehearsal) you can make these stronger and nicer looking and much easier to work with by doing a running lock-stitch down the sides. This isn't a blind stitch...we aren't trying to hide it here. No need to work from the bottom and just pick out one or two threads! Just pinch the fabric and do a fast whip through it.

Stitch down to the corner, do the same button-hole stitch there, and lock it. Sure, with a decent machine you could do all of this on the machine. But this is almost as fast (if you are used to quick-and-dirty repairs with a hand sewing needle, as I am!)

And it is done. There is just enough space in the bag to tuck some of the slack of the element in there after you've taped it to the actor. My cast for this show is 'tweens, tho, so you won't be getting any pictures of the packs in use.

In this case, we kept the longer elastic and safety-pinned to make them shorter. Since we only had to do that once it didn't cost us much in dressing time. As with all bags, they are worn OVER that clothing that will never be removed during the show, and UNDER everything else. That helps keep the bag from flopping about, and also keeps the microphone cable from getting caught on anything.

The "Care and Feeding of Wireless Microphones" series:

The Basics of Mic'ing a Cast
The Basics of Mic'ing a Cast II
The Basics of Mic'ing a Cast III
The Basics of Mic'ing a Cast IV
A Few Simple Rules for Wireless
The Two Nations of Sound Reinforcement

Theatrical Sound Design series:

So What is Theatrical Sound?
The Basics of Sound Design
The Basics of Sound Design II
Six Simple Rules for Getting a Good Voice-Over

Monday, May 16, 2011

Microphone positions reviewed

Just a quick post here, based on finishing a short run with 22 channels of wireless microphones.

My favorite position sonically is still forehead -- the "Angler Fish" position as one of my young cast called it. I know some people prefer to stick the mic at one side of the forehead or the other but I just go dead center (or at an available part in the hair). Resist the temptation to stick it as low as possible. Unless the actor has very long bangs or a wig, a tape-width from the hairline is plenty. Much of the sound it picks up is off the resonant cavity of the forehead. It sounds GREAT on good female singers, can reduce nasality on other actors, and doesn't usually need the corrective EQ of the other classic positions.

So. A narrow strip of tape on the wire, right behind the mic head. Cord goes up along the center of the head and is held with two hair clips or bobby pins. Depending on the hair length in back, you might add a wider strip of tape across the nape of the neck. Then down into the neckline of the costume.

There is what is known as a "halo rig" which is a bit of elastic thread sized to the actor that secures the head of the mic. Properly done, it is nearly invisible. I've never used one myself, though, so have no advice in making one.

The fall-back position is ear. Many actors prefer it for some reason (although my clever young cast also had a name for it; the "Parasite" mic. Because they felt it made you look like you had a bug crawling on you.)

In any case, resist the temptation to angle the mic down towards the mouth. Again, you are trusting the acoustic coupling of the body cavities. Also, there is a nasty resonance in the hollow of the cheek that makes the mic sound muddy and muffled and requires a ton of EQ to ameliorate. (Try humming and press your finger to your cheek. You'll feel that low-frequency resonance in your fingertip).

Instead, feel for the "cheek bone" (zygomatic) and place the mic there, a narrow tape-width from the sideburns (or whatever hair the actor has in front of their ear). The mic cable runs parallel with the line of the cheek, aiming basically towards the tip of the actor's nose, but is back, as close to the hairline as you can tape it.

Run the cable behind the ear and tape behind the ear: low, around the earlobe. Then pull the cable the the center of the neck, ask the actor to turn their head the other way, and tape at some arbitrary point about half-way between hairline and collar. Much depends here on how the actors wears their hair, and what the costume looks like.

In all cases, cables run OVER the furthest UNDER garment; under as much as possible so the cable doesn't get snagged, but NOT against skin (because skin conducts, and will drain RF energy.)

In some cases the voice is so weak you will have to run an ear mic low, bringing it close to the outside corner of the mouth, and tape on the cheek. Don't do this unless you have to.

There are a couple of series of microphones designed for this position, with an integral wire boom. The Countryman E6 (which I was using this show) has a couple of issues to note. First is that the wire boom is sensitive to handling noise. It is best to tape the mic to the actor's face close to their ear, but leave the rest of the boom with a slight air gap, so it is suspended in front of the actor instead of being in contact with their fact. Also, the connector at the rear of the ear clip makes securing the mic there problematic.

Countryman apparently will custom-make a set without the connector. Baring that, avoid putting tape across the connector itself, as it tends to rotate and introduce crackling sounds. The best option is taping the wire below the connector.

Do NOT let the boom drift until the mic is under the actor's nose! You will hear nothing but Darth Vader noises the entire show. Also do not allow it to go in front of the actor's mouth; bend the boom in whatever peculiar ways you have to to prevent this. Countryman does make a shorter boom for younger actors, fortunately.

The "Madonna mic" (personally, I'd prefer to reserve this term for a boom mic with a large foam pop filter on it) is a very different sound. It is more than anything like a telephone voice; very thin, lots of lip and breath noise. Reach for this position for two main reasons; because you want a specific sort of sound, and because your actor is so quiet you can't get enough gain before feedback without it.