Sound reinforcement for 400 people

Question

I'm working with a musician who conducts workshops for corporates. He's a percussionist and uses music and percussion to teach them stuff. This time around he's working with about 400 people in a huge ball room. He plans to split them up into groups of 40-50 and get each group to "perform" percussion with simple objects (or even hand claps/foot stomps). Considering there are so many people he wants each group to hear what the other groups are up to - as it's important to get everyone to perform together. So, he wants to mic up each group (unobtrusively) and use a PA system to amplify the sound. His brief was "Not too loud, just loud enough to reinforce the sound so that everyone can hear what's happening".

My initial thoughts were:

1- That's a lot of people! 2- Possible feedback issues 3- Can't use too many microphones/cables - something is bound to get knocked off/damaged/get in the way 4- Use multiple booms around the room, except being an indoor space there are bound to be complications.

Any ideas? Choices of microphones? Maybe go wireless?

I also thought of PZMs - but can't see the practicality in it.

All ideas however bizarre are welcome. :)

Thanks!

Answer 1

Oh live corporate sound, how fun you are.

Here's what I would recommend for the purposes of being reasonably cheap, and reasonably sane:

• 2 powered speakers on sticks at the front of the room with a simple mixing console. 400 people is a decently large crowd, but you're also not performing a rock concert.
• 2 wireless handheld mics (Shure or Sennheiser) on boom stands on either side of each group. As nice as it would be to have people get up and circle up, they'll probably stay seated in their section of the room. Place a mic to the side and in front of the group. They have pretty good pickup for this purpose. I'd go wireless for two reasons - no cabling to fuss with, and you have the ability to move and place them quickly. You'll want to get them out of the way when this exercise is over. Total of 8 to 10 mics depending on the group size. If you've got smaller groups, 1 per would be fine.
• Don't forget to get 1 or 2 wireles mics for the performer - he'll need 1 to mic anything he's percussing, and 1 headset mic to speak and walk around during the exercise.

Feedback shouldn't be an issue as long as the front-most mics are facing away from the speakers.

Most rental houses should be able to provide a sound tech as well, unless you're doing that part :)

I honestly wouldn't do anything more than that. Bringing in boom mics is costly and a bit of a hastle. This isn't for a professional recording, it's for a fun exercise. Save yourself a headache and just get a rental. I just priced out a wireless system that about meets these specs and it came out to over 20k, without the mixing console. Until you are doing a ton of gigs, rent!