Need Help With DIY Diffuser Design...

[Here&ThereStudios]

Hey, as we are in pandemic-mode I'm trying to get a better sound in my rental and the walls can't take a heavier diffuser like the more common DIY diffuser you see made out of blocks.

I'm temped to make some quickie DIY diffusers but need to understand one detail before I proceed. I need to know how important all of the different surfaces are in scattering sound. I was going make a simple frame/box and cut 3 channels in the bottom and top pieces, then slide in a some thin lattice boards at different depths. I was going to stop at that. How critical are the "green" surfaces in the third example? Do you need both dimensions to get proper scattering?



Anything worth doing it worth doing right, so I don't want to overlook something critical. Any scientists out there who can school me?

[losthighway]

This is not very scientific, but I got some 1"x 1" furring strips. Cut them at arbitrary lengths with a chop saw (in between .5" and 6") and then nailed them to a piece of wood in rows with random selections of length.

Looks cool. Seems to work well. Took a shit ton of wood.

[floid]

Looks like you're contemplating something similar to a quadratic residue diffuser. Searching that may find you some useful info. It's a rabbit hole, have fun.

[digitaldrummer]

I know its not as much fun as making it, but what about something lightweight and ready-made like this?

https://www.gikacoustics.com/product/2a ... bsorber-2/

and you can mount it like a picture frame so if you move, you can take it with you. you could also try a couple and add-on if you need more the big wooden diffuser's can get pretty heavy.

otherwise, if you just need absorption, Owens Corning 703 works well (once you wrap it with cloth) - you can hang it on the walls for mid-high absorption, or stack it in the corners for bass trap ("superchunk" style).

[markjazzbassist]

tapeop had an issue where they had all the design and instructions to make your own DIY one.

https://tapeop.com/tutorials/83/diy-diffusors/

enjoy

[Here&ThereStudios]

Thanks all, I've already got some absorption panels from GIK, I just need to liven up a small room a little.

As I said at the top, the typical DIY diffuser will just be too heavy for me to mount. I'm hoping my slimmed-down design will still help some but at a lighter weight but as I'm not an acoustician I don't know if it will work. It does in my mind! Plus, I've already got a lot of the raw materials so I could put this together on the cheap. Despite the pandemic I've got a lot of pots on the stove so I don't want to waste a bunch of hours on something that will net me no noticeable effect. On that front, thanks for taking the time to read this and I hope you're taking care of your coconut and you've got people you can lean on. Good luck everyone!

[markjazzbassist]

Thanks all, I've already got some absorption panels from GIK, I just need to liven up a small room a little.

As I said at the top, the typical DIY diffuser will just be too heavy for me to mount. I'm hoping my slimmed-down design will still help some but at a lighter weight but as I'm not an acoustician I don't know if it will work. It does in my mind! Plus, I've already got a lot of the raw materials so I could put this together on the cheap. Despite the pandemic I've got a lot of pots on the stove so I don't want to waste a bunch of hours on something that will net me no noticeable effect. On that front, thanks for taking the time to read this and I hope you're taking care of your coconut and you've got people you can lean on. Good luck everyone!

if you look at the link i posted you are able to use any length, just use the proportion mentioned in the article. so you can make it 1mm, 2mm, 3mm, 4mm if you want. doesn't have to be in inches.

[MoreSpaceEcho]

I think you'd get better results making poly diffusors. Lightweight and easy to make.

Make a frame of 1"x3"s, make it 47" wide. Take a sheet of 1/8 plywood, bend it and fit it into the frame (you'll need a friend). Dampen the panels with some pink fluffy on the back. Done.

[The Scum]

For a simpler, lighter, hangable diffusor, look up the "polycylindrical" diffusor.

Piece of masonite, bent into a curve, over a more rigid back piece. With a little effort, you can make convex & concave ones to make them more irregular.

[The Scum]

To follow MSE's thought - you can get bendable/flexible plywood, where the grain is all oriented in the same direction. Much easier to bend than regular plywood, where the grain alternates, making both axes more rigid.

[MoreSpaceEcho]

Yeah, it's real easy to bend. Smaller ones you can do yourself, I have a bigger one that's 6' high, that one I needed help with. The bending's easy, it's getting it to stay in the frame that requires help.

Once they're in, they'll stay just fine. You can put in a couple finish nails just to make sure though.

[Scodiddly]

That curved surface design goes back forever - classic design. Probably where I'd start.

There's a youtube channel based out of Chicago here called "Experimental Sound Studio", and they have some big QRD panels made out of that rigid pink insulation foam. It's even their logo!

Ever since the pandemic started they've been going crazy putting up various home shows from all sorts of crazy experimental music / noise / whatever acts. Pretty cool stuff.
https://www.youtube.com/channel/UCChJYT ... NgUb_pIiqA

[digitaldrummer]

I have some of that rigid blue foam sheathing/insulation that is used in house construction and I've always wondered if it could be used instead of wood to make a very lightweight QR diffuser? The foam might be too porous, but if I could find some spray paint that wouldn't melt it, it might make the surface a little more reflective? it's cheap too...

[MoreSpaceEcho]

I'm far from an expert but AFAIK real lightweight stuff doesn't work for diffusors, you need something with some actual mass.

It's a minefield of shit but the studio acoustics forum at gearslutz actually has a lot of good info on this stuff, it's worth digging through some posts. You'll quickly recognize the half dozen people on there who are worth paying attention to.

[Scodiddly]

I'm far from an expert but AFAIK real lightweight stuff doesn't work for diffusors, you need something with some actual mass.

Certainly an interesting question. Maybe it's a diffusor at high frequencies, and an absorber at lower frequencies? An abffusor? Diffsorber?

I have some random large pieces of the 1" blue foam that were left here by previous owners, maybe I'll find time to build something.