An inexpensive, simple, but effective choral shell

How to build a simple yet very effective choral shell for $400.

The community based show-chorus I sing with, the Maple Leaf Singers, wanted to do something to improve the sound of our performance for our big fund-raising show - we sing over 15 times per year, but just a pair of shows bring in our critical revenue.

Massey Theatre, the place hosting the big shows, is a big box of a place, with a huge backstage and theatrical fly system. Our singing vanishes into the void, and we tend to yell because the sound balance is off - we can't hear each other. Yelling is not good and lowers our pitch, yet the audience despite our being miked to the limits of feedback, still can't hear us well.

The current option of choice - miking every performer - is not an option for a 60-member group. Nor is changing the venue. In desperation we decided to try sound reflectors, and to my modest surprise (I'm always surprised when something I build succeeds) - it worked better than we had hoped.

Consulting the local experts

First here's what researching with the local theatre people - the ones we consider to be keeners at their craft.They told us that a shell would do nothing for the audience, but would help us hear each other. This alerted us as to what to expect default, so that we weren't disappointed and could design around the default limits.

What our goals were

We wanted to, in decreasing importance: 

1. Have the audience hear us - well duh! but today's audience wants volume

2. Hear each other - often taken for granted

3 Hear our monitors- without feedback

4 Hear the audience - this last is what makes it fun!

Studying the shapes of the commercial units, it turns out that a traditional choral shell - costing thousands of dollars and weighing many pounds, does not reflect the sound evenly - by design it scatters it within the choir, so that it primarily supports objective #2.

With modern materials, it seemed might be possible to satisfy more of the objectives, by focusing the sound at the audience, and by "piping" it from one side of the chorus to the other. 

So what we built

Our choral shell system has two components, one not very visible, the other very much so. Both are made of the material Coroplast, the lightweight material using to make signs.

1. The invisible - but important! - black railing cover of coroplast

We now use this for all performances, as it is easy to set up and gives us consistent sound

 

 

 

2. The visible white shell, flown by the theatre system

This is only for use at the big theatre, directing some sound to the audience and some audience sound to us.

Note that it also acted as a "sonic pipe", transfering sound from riser-left to riser-right and vice-versa.  

 

 

 

What it looks like: one segment, front and back:  

 I used 3 thin wires to bend the panel.

 

 

 

What it looked like in practice, with the segments all linked together with Velcro, flown and lit:

 

 

 

 

 

 

The wonderful Massey staff were keen to try it, and suggest improvements.

Results

The choral shell was very effective in a number of ways, and seemed to have no downside:

• The intra-choral sound was excellent: we could hear each other, didn’t yell, stayed on pitch, and could dis-regard monitors that were too loud or too quiet
  
  
• The shell apparently focused the audience attention on the choir, making us look closer and more intimate
  
  
• We could hear the audience a bit better; they sounded closer
  
  
• We had remarks like “Wow, you guys really had a lot of very difficult harmonies this year!” 
  
  
• I think he choir most benefited – no-one’s voice was hoarse after 3 days of singing - the first time ever.
• Our pitch was good: I know that the piano/track never sounded sharp and our chorister with perfect pitch reports it was good
  
  
• The effect was like singing in the our normal rehearsal hall, perhaps with an even better unit sound - I could hear the ladies on either side and felt a solid crisp group sound. |
• and the cost was low - $400 for 10 sheets of Coroplast, lots of Velcro, and some wood.

SO if you are interested, let me know, and I'll post details of how to make your own.

Ken Rushton.

 * The Massey Staff also borrowed a new high-grade overhead microphone that helped.

Comments

[Fred Saurmann]

I'm curious as to how this project was completed, I'm technical director of a church with a choir number anywhere from about 30-50 some members. We seem to have the same dilemmas that you've experienced. I would love to get some more information on how you completed this project. Thanks for your insight!

[Rick Ward]

Ken,
We are a symphonic chorus with 50 - 90 voices and accompaniement ranging from piano, bass and drums to a 40 piece orchestra. We also perform in several venues, including high ceilinged cathedrals. I have been charged by the board of directors with getting information about choral shells.
Your system looks fascinating. Any detailed information you can send me would be greatly appreciated.

[Ingrid Ojala]

I'd love more details for our choir of around 40!
thanks!

[jeff Lyon]

How inventive!

I'd love to have the details on this shell. It looks like it would be perfect for our church's multi-purpose room when we have our Christmas and Easter programs.

Any information would be greatly appreciated.

[Joanna Davis]

Hello, Ken

Could you please send me the details? I am a Sweet Adeline from Northern California and am in charge of our regional competition in April. We had been using a choral shell belonging to the Calif. Music Educators (CMEA) for our 13+ choruses of about 500 singer - but the shell is no longer available and I can't find another shell in all of California ... and the cost of purchasing a shell is quite prohibitive.

I would be grateful to see your solution.

Thanks.

[jeff Lyon]

What a great idea! I'd love to have more details. Could you send them to me? THANKS!

[Zeke Johnstone]

Hi Ken,

That is some amazing work you guys did on your shell!

I am helping with an event where there will be 500 teenagers singing. The venue is in a fair ground pavilion and the sound is terrible. Can you send me the details for building this choral shell. Thank you so much.

[Mike Maughan]

Hello Ken, thanks for posting this and generously offering to share the details! We have a choir of 60 as well and are always looking for ways to enhance our and the audience's experience. By all means, please let us have more details we can decide whether to mount a project to build one. We are the High Spirits Choral Society in Vancouver BC, musical director Ieva Wool. My name is Mike Maughan, Board President of HSCS. Thanks again!