Anyone else here interested in, or built, or even heard Folded Well Diffusers??

These are made from cherry wood, except for the ply board backer

@brunomarcs - I just also considered using popsicle sticks with the well width as the length cut, it would probably help to go from one side to the other and use them to prop it back into shape, for little investment?

@brunomarcs - I have made QRD17 also out of cherry wood. When I re-sawed the beams into the dividers I ran them on a joiner each time to get a perfectly flat surface to run along the guide, and still it wanted to bow a little. Certainly not what you’ve described though.

Have you considered making a comb that will have teeth that hold the divider fins in place at the correct pitch? I’ve seen a few diffusers using that method to get the centers perfectly aligned, maybe it could work for you?

I find building with wood to be so much fun, and almost therapeutic even.

How many did you make of these?
Where did you position them?
What were your listening impressions please?

@slaw - I suppose they will be collectively, reasonably heavy.
I made them 4ft long, and they are about a foot wide. Yeah, a dozen or two of them will get some mass, they weigh just under 23lbs each. The 5ft tall QRD 17 diffusers I made took two of us to lift, and I was admittedly the smaller fella doing the lifting.

I suspect in order to be reasonably rigid though, the structure needs to be made of a material that will not yield too much?? I’m still learning about diffusion, and getting better woodworking skills in the process.

@oldhvymec - it looked interesting enough to make this crazy builder have a go at them. I already have 6 built, then it occurred to me that I should ask in here if anyone one else found them beguiling enough to build, it appears there is.

@brunomarcs - ok, so the first diffusers I built were Denis Foley’s Acoustic Fields QRD17, I have two glued up, four cut out.

However these folded well diffusers are a slightly different animal, and I have only got a 24’ by 15’ room. Because of this I went with folded well on the rear wall.

I plan on building the carbon absorbers and stacking them, slaw was bang on when he said that they’re heavy. The absorbers are even heavier than the diffusers.

The ceiling I’m not entirely sure how to tackle yet, I need some measurements and research to get a better idea of how to proceed.

Now, with your diffusers, there is a distance from the diffusers that you need to be in order for them to perform at their best, your room limits this.
Have you heard of BAD? Binary amplitude diffusers, and you can put absorption in behind them as well. I have read that .5" holes do deal with lower frequencies much more effectively.
These BAD panels are less restrictive in the listening distances in order to be effective. Do you want more information?

@brunomarcs - yes great idea and yes.
Don't forget to use the Golden ratio for room acoustics

@brunomarcs - I haven’t actually heard the carbon technology of Acoustic Fields at all. When Dennis spoke of how he come to discover the technology by accident, it reminded me of what was told to me when I visited the Genolan Caves.

It wasn’t too much of a leap to believe what he was saying about the micro pores in the activated charcoal is powerful for low frequency attenuation/absorption.

My plan is to get the diffusion done, take some measurements and build (from his plans and his DIY activated carbon) some ACDA-12 M type modular bass absorbers.

I can’t speak to the carbon absorbers, I haven’t heard them as I stated, but his QRD from plans work very well. I have only two assembled of the four cut out, and I have the two in my room, we love how they look and work in my room.

I spent $2000 on cherry wood and some more on glue, that’s just materials for my four QRD17 diffusers if you need some sort of idea. There is of course a big difference in cost between cherry wood and MDF.

I wonder if he has a customer near you, that might let you hear his room, to get an idea? I’m in the middle of west Texas, guns and big trucks galore, but audiophiles are not common out here. So I just went for it, so far I’m happy with the results.