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Jun 10, 2012


Terri Ellerbach

Hi, Ken!! What a genius you are! Let me know if you still could send plans for us. We are a small elementary school and have our programs in a gym....we need something!


I would love plans for my elementary school, please!

Young Lin

Hi Ken,
Please send the plan. We are a small singing group, and have no budget for expensive panels, and our performance definitely need your design. Thank you very much!

Renee Von Kiedrowski

I am the secretary of a rural parents music boosters program for our local Jr/Sr High. We would love to get the plans from you since we just can't currently finance a commercially produced unit for our kids.

Teresa Ellis

We have a small church with a choir of about 30 that we want to put a shell behind. Is it possible to use your system as a portable unit? Could you please send us your design? Thank you very much.

dan needham

Thanks for your info. Making some kind of shells has been on my mind for a bit since we have a perfect way to permanently mount them on the back wall of the choir loft in our church.
Weight and portability is not an issue, so I'm wondering what would be the best choice of material for acoustics? We could use plywood and even sandwich (double it) with space in between say 4" so it would be hollow. I would appreciate any thoughts you would have on this.
Thanks, Dan

Jane Griffen

Please send the plans. This will be a cure for our University stage that we can afford!

Jane Griffen

Please send plans as soon as possible.

Eric White

Hi Ken:

Thank you so much for your wonderful choral shell design.

We have five 4-step Wenger risers, which set up in an arc, so we needed a curved shell. So, we supported each of the “flying” sheets individually, so we could position each one separately behind the risers.

We supported the shell pieces with lighting stands (ADJ LTS-2 – http://www.adj.com/lts-2). These stands are rated to 80 lbs and extend up to 12 ft. We needed 5 of them and the total cost was ~$650 CDN ($109/each plus taxes and shipping).

The cross bars are 4 ft long and come with 4 bolts with wing nuts. We replaced the bolts with longer ones and bolted 7 ft long pieces of 1x4 to the cross members. We attached the flying shell pieces to the cross members with ¾ inch Velcro (3 18” strips per shell fragment).

The shell fragments were 4x8 pieces of coroplast. We put the Velcro strips slightly lower then midway (18” up from the bottom).

The other change we made was how we established the curve on each shell piece. We cut 1” slots @ 1ft intervals along both top and bottom edges of the shell pieces. We tied lengths of heavy fishing line (actually whipper snipper cord from a long deceased whipper snipper) into 44” lengths with knots at both ends and washers inside the knots. To create the curve you simply slip one end of the cord into a slot (with the washers at the back) then slip the other end of the cord into the matching slot on the far side of the coroplast sheet. These are easy to assemble and take apart.

It’s a bit tricky to get the length between the washers consistent. I tied a knot on the end of my roll of cord, cut the cord longer than needed and slid on both washers. Then I measured the 44” and marked the cord with a magic marker. Then I used that mark to locate the second knot. The mark needs to be just on the straight cord in front of the finished knot.

We tried several distances between cords and found that with 24” spacing the top edge of the shell had a bit of a wave between cords, but with 12” spacing the top edge of the shell was nice and straight.

Our total costs were $1300. All our costs were consistent with yours with the marked addition of the lighting stands. However we now have a sound shell with which the choir is totally pleased and which should last us for years.

Many thanks from all of us to you.

All the best
Eric White
Nelson Choral Society

Karen Wilmus

Please please send me the plans!!!

Chloe Vassmer

I would be very appreciative if you could send me the plans!

Ken Rushton

I've posted the first of three articles on how to build a choral shell: http://www.musicscienceguy.com/2015/07/choral-shells-for-the-risers.html
This article focuses on making an acoustic cover for your risers.

I hope this helps. The second article is about the visible white upper riser, and will be a challenge to write.

Michael Stroupe

I serve as stage manager for The Palmetto Mastersingers in Columbia, SC. I would love to have a look at plans for your design. Do your plans allow for support of these curved panels from the ground instead of suspended from the ceiling? We have 3 level, 32'x12' risers when fully assembled. We would also require some sort of black panels to attach to the back of our risers for the area below the curved panels. Thousands of dollars for a shell is way out of budget for a volunteer non-profit group like us. We number anywhere from 50 to 80 singers depending on the year.

Dr. JS Moir, DMA

Dear Ken: If I could have the plans, it would be a godsend for the very small HS Choir I am directing in two weeks for our Spring Concert, in a barn of church, and with an Admin that won't/can't see the necessity of actually amplifying a choir for the audience's sake, as well as for the students!

Ken Rushton

PS. do the lower part first - it gives you a faster setup. Cover the riser steps as well, but do be careful never to introduce a tripping hazard.


Ken Rushton

Neil, RE: "could you tell me the thickness of the 'coroplast' you used? We here[Australia] have the option of, e.g: 5mm or 3mm"

I just measured mine, it is 4.12 mm. I would go with the heavier version, partly because it will be easier to handle. I expect the sound reflection will be slightly better with the thicker material.


Neil Marsh

I may be a bit late with this ... but could you tell me the thickness of the 'coroplast' you used? We here[Australia] have the option of, e.g: 5mm or 3mm. I think the thicker the better, both for rigidity & sound reflection ... what is your view, please?

Philip Lehman

From your posting I assume you are retired now - as am I. I have been asked to build acoustic shells for our church choir and this seems to be the most effective, lightest, storable and inexpensive method available.

Can you send more information or build instructions??

Andrew Adams

Hi Ken,

I'd really like to see your plans for this. We're a 25-30 voice choir and $6K for a shell is out of the question. We often sing at outdoor venues and a variant of this could solve lots of problems!


I am SO interested in getting all the details to build this type of shell. I teach music at a small elementary school. The building is very old, and the only "stage" is on one end of a sunken gym. Basically, there are big wooden doors that can be opened and a railing at the front of the doorway so audience could sit in chairs down on the gym floor and the kids could perform up behind the rail. Only problem is that they would be standing in a main hallway. We need a way to make a "back" to our stage to block sound and sight lines down that hall. Please help! :)

Ken Rushton

I am unable to do any major postings until Jan 6, when I retire to specialize in:
1. learning to play my jammer.
2. post fun things about Music.
I promise that I will post all that I know about the choral shell in January. I will finally have time to do so.

A tip for the meantime: I created 8" high riser step covers from coroplast. These were very successful.
The boost reflected sound and the stopping of sound sneaking around the back of the risers and making the sound muddy made it easier to hear each other and the audience seemed to like it.
Just take careful care that the feet can't catch on a protruding piece of plastic.

Janet Vrudny

I too would like to hear the information regarding your homemade choral shell. We too have a multi-purpose gymnasium that we use for concerts and we desperately need a shell. Thanks Ken for any information and help!

Ken Rushton

Hello all.
I'm unable to post a long reply to your pleas, as it's show season. I tried making a video, several months ago, showing how I bend and fly the upper shell, but I learned that (1) videos are very time consuming. and (2) that I didn't have (or make) the time needed to do it - I kept doing a bit, getting interrupted, restarting - you doubtless know the drill. Instead, here are some notes:

First, put up the black railing cover over the back of the risers. This is cheap and easy to do. I presume you currently have black curtains stuck on with velcro? If so, this is easy:

- put the 8' x 4' sheets coroplast against the railing, and trim it to the height of the railing (save the trimmings).
- Cut the sheets down from 8' long to exactly 4'
- Protect yourselves against plastic-caused "paper cuts" by wrapping black electrical tape over the top edge.
- then stick 1/2 inch squares of velcro on the back side of the plastic sheets, about one per every 8-12 inches. Don't use too much, or the coroplast will be stuck on so tightly that you will bend it when you pull it off.
- If you don't already have velcro on the back railing, buy enough velcro to cover the top bar,
clean it carefully with solvent or a good detergent, and stick the velcro on securely.
- To speed up setup, put an big "arrow" on the back-side of the sheets pointing to the top edge.
This is a big help.

Extra tip: to make the sheets easier to handle and store, suggest drilling a thumb-size (1 inch or so) hole in the top centre of the sheets, to give them a grip, and put a 1/2 inch square of velcro on all 4 corners, so that the stacked sheet layers would stick together and can be put in the truck easily.

That's it for how to set up the riser-back part of the choral shell

More to come, time permitting. Ken.


I'd love to get the details on how to make these!

Francis Marien

Hello Ken,
I have been researching exactly what you did for your music shells. Our Chorale does fund raisers for not for profit organizations in the area. Purchasing shells is cost prohibitive because we rely on only donations from business to supply music and stipends to the few musicians we have to hire for our two to three concerts per year. If you could send more detailed information on your construction technique it would be very valuable, in particular the method of securing the wire to the material without tearing or breaking it. Also we do not have the luxury of flying them and have to stand them up on the stage flooring. Any ideas for this would also be helpful. Thank you for any information you could supply,
Fran Marien

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