Alternatives to PA speakers might increase intelligibility

brubart

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Joined
Jul 31, 2009
Location
Weaverville, NC
It's often difficult to understand children talking in a stage play because of muddy room acoustics and poorly designed PA systems that feed back easily. Wireless headworn mics can help, but not every school can afford them or control them effectively. So floor mics are used instead.

How about this: Place a floor mic on the stage. Feed the mic signal to a speech recognition device, and display the actors' lines on a video screen. It would distract from the stage action, but at least you could understand the lines and follow the plot (kind of like closed captioning).

Another option: broadcast the mic signal (or the sound-mixer signal) to an assisted-listening system of headphones. But you'd need hundreds of headphones.

Maybe broadcast the voice-recognition display to the smart phones of audience members. Or live-stream the audio to the smart phones (ideally with very low latency), so the audience can listen on earphones if they prefer. Then they can hear the actors clearly.

The best solution might be to re-do the loudspeaker placement and directional pattern to prevent feedback and increase intelligibility. Place the loudspeakers close the audience, far behind the mics. Use loudspeakers that focus sound on the audience, rather than spilling the sound onto reverberant room surfaces.
 

jkowtko

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Jan 9, 2007
Location
Redwood City, CA
I had the mispleasure of watching all of our kids' elementary school stage plays ... cringing the entire time at how poorly the sound system was set up and being used. But I wan't in the PTA and did not have the opportunity to offer my services beforehand.

As a simple first step, I would suggest the following:
* set up a line of pencil condensor mics across the front of the stage on low mic stands, about 6 feet apart.
* get the teachers to block the play so that the kids are always standing towards the front of the stage, and facing the audience as much as possible.
* if you have ceiling mounted speakers, add some more speakers at audience level on the sides of the stage, and maybe a fill or two in front of the stage.
* if you have a deep audience seating area (i.e. > 50 feet), consider adding a second pair of speakers on the sides of the audience halfway back.

Much of sound reinforcement is just that, reinforcing the original sound. Often you only need to provide a small amount of amplification to make a small voice much more audible. Having the extra speaker power will allow you to keep mic gains and volumes at moderate levels. To some extent this is what is done in professional theater. If you've seen those racks of Meyer speakers surrounding the stage, they use ridiculous amounts of speaker power but keep the volumes at fairly moderate levels for vocals. Yet you can hear the vocals clearly.
 

chausman

Chase
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Spokane, WA
if you have a deep audience seating area (i.e. > 50 feet), consider adding a second pair of speakers on the sides of the audience halfway back.
You just have to be careful, because you can end up with bad phasing.
 

jkowtko

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Joined
Jan 9, 2007
Location
Redwood City, CA
You just have to be careful, because you can end up with bad phasing.
True ... as an option to this, maybe just put more speakers in the front of the stage to make the sound field as solid as possible. Phase issues won't be great, but your goal here is to make the kids heard by their parents, there is no goal for sound quality ;)
 

rwhealey

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Joined
Sep 7, 2008
Location
Denver
The best solution might be to re-do the loudspeaker placement and directional pattern to prevent feedback and increase intelligibility. Place the loudspeakers close the audience, far behind the mics. Use loudspeakers that focus sound on the audience, rather than spilling the sound onto reverberant room surfaces.
Hmm... Follow good design practices, get good results?

The problem with the wifi/personal audio distribution is twofold - first, getting the latency and delay right for every audience member is impossible. The audience members in the back will hear the assisted listening/wifi sound before the direct sound arrives. This is less of a problem with assisted listening since you are assuming the person using it can't hear the direct sound. The second problem is that sound is no longer coming from the stage. It's inside your head. A goal of good sound system design (and IMO the one most often not met) is to give directional cues to the audience.

You just have to be careful, because you can end up with bad phasing.
Not if the delay is set correctly. You shouldn't notice properly set delay speakers.
 

chausman

Chase
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Location
Spokane, WA
Not if the delay is set correctly. You shouldn't notice properly set delay speakers.
True. My point was simply that it's more complicated than just adding speakers.