Seeing the National tour of PIPPIN, I noticed that the cast was using facial mics as opposed to the set-up one usually sees in broadway/NT productions with Mics in the wig, on the forehead, or near the ear. Does anyone know why they would be using facial mics for this production?
Could also have to do with any costume/hair changes making hairline impractical? I can't recall the show in detail enough to think what might cause it, though.
They are actually called miniature microphone headbands. As far as what is "usually" used in shows, certain styles of microphone are more common, but each is suited to the demands of the show and its style. A show aiming for more realism will opt for small mic heads, well hidden within the hairline where possible. In that case, you then deal with issues of placement based on hair styles, whether or not hats or worn - in some cases building a second mic into the actual hat because a hat will change the sound quality, if the actor is bald, etc etc. in those cass, you generally want the mic placed as center to the head as possible, because moving it to the side affects how it picks up sound. It is all very specific. The mic is then attached with a combination of headbands and clips, depending on the circumstance, and the wig placed over the cable or the hair styled around it. With a miniature microphone headband, you are better able to achieve a uniform mic placement for all actors and, in the case of a show like Pippin, provide a more sturdy support to keep the mic in place during physically demanding sections of the show. It also allows you to get the mic closer to the performer's mouth, meaning the mic doesn't have to be worked as hard to pick up the vocals and you can get a more pure capture of the actors's voice. It will always boil down to a balance of what visually will work for a production and what will provide the best sound.
It has 100 percent to do with sound control and isolating actors voices. The face mics are generally more effective at isolation than those in the wig line.
broadwayguy2 covered it pretty well (as he usually does), but in the case of Pippin it's less of an issue of "sound isolation." Hairline mic placement *would* work quite well in the NY production for example, as it's not an over-amplified show. However, with the amount of helmets/crowns/headpieces being used, it would be nearly impossible to use a hairline microphone on Pippin, Charlemagne, Lewis, and all of then ensemble members without also mic-ing each helmet/headpiece (which is prohibitively expensive and dumb). With all of those people then needing to be on "boom mics," the other principals require the same mic placement in order for the production to sound cohesive. Add into that the amount of sweat that's produced on the stage, and how little Pippin comes offstage where his mics could be dried off, the boom/headset mics (which are slightly less susceptible to sweat-outs) are the clear choice for a production like Pippin.
In the case of RENT or Rock of Ages, it's all about getting the show as loud as possible before feedback.
Edit: also in the case of "Pippin," the show is about actors putting on a show (in which microphones are used), so there's no real need to try to hide the mics.
That's weird. I never noticed any of the facial mics in Pippin aside from the leading player, who I just assumed wore one because she was supposed to be an actress, and thought it actually kind of worked well with her costume. That reason does make a lot of sense, though.