I'm looking to build some relatively cheap poly-cylindrical diffusers, and so far I have thought of two options:
1) I have sourced some concrete forming tubes that are already cut into half cylinders.
2) I could bend some 3mm pegboard/hardboard (or possibly plywood, not as cheap): a cheap option I thought of was to bend it by attaching wire to holes at either side and then tensioning the wire to bend the material, but in this case it would not be mounted in a frame, which I gather is desirable.
The pre-cut concrete forming tubes seems like a quick option, however, larely due to shipping costs it is 2-3x more expensive than option 2. In addition, from the FAQ it is clear that a Euler-Bernoulli buckled curve, or the ability to make curvatures of different radius, is favoured over cylinder sections. In that case, I could happily go with option 2, but, two questions:
Does the density/thickness of the material matter for this sort of design? I am not sure of the density of the cardboard material (option 1), but they are 9mm thick and each half-tube weighs ~6kg, so they are pretty bulky things in comparison to the pegboard, and secondly, will the holes in the pegboard be a problem?
This is my first post, so to introduce the space I am trying to treat, it is 5.5 x 3.75 x 2.2 m. It is currently treated with bass traps and broadband absorption (Rockwool) - this got rid of the flutter echo, but it is now sounding a little "dead", hence my interest in diffusers.