two questions about absorbing panels

Do these look okay? They are not very deep, 3 1/2" x 16" x 24" to be exact.

I will load with a rockwool after I fix up the 1/4" back panels.

Being somewhat shallow as they are, will they be very effective with heavy rock wool behind stand mounts?

Next I am planning to make at least one larger diffuser framed the same way, also loaded with RW. Something other than skyline. 24" x 48" x D? If I were to style it the same way as the three imaged, only fashion slats in an every other pattern across the front. Questions are how wide and how widely spread apart should they be to turn that absorber into a panel that does some of both for MF & HF?

Similar idea to certain dual purpose acoustic panels popular on the open market atm, the multi frequency square shapes.


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Usually need more absorption for some areas.
Other areas a combination of absorption and diffraction.

So rockwool or foam stapled to the wall would do same thing.
have absorption in a small area then be reflective in areas not covered.

for high absorption easy fill the wall area with common foam pads.
even add layers. foam is ugly but its just absorption.
1 or 3 layers foam works. Then add drapes or tapestries in front
to make it look pretty or decorative.
I forgot to mention, the multi would go elsewhere.

BTW that was also kind of my other thought, a panel VS no panel where sound is free to reflect is the same thing essentially. But that it would be less accurately controlled as a specific designated panel would.

At times I keep forgetting to stop thinking and just keep it simple.

Comparing mine to a similar panel only that one has double its rock wool thickness, 7". If the larger one is effective catching all of the the sound then In theory 3 1/2" depth should do a comparable job if speculated to be "too thin" by Joe the audiophile speculator . Because the sound will dissipate a second time on it's return path, after it reflects off the wall directly behind the rock wool.

I have to work with the room, hence depth. A few more feet in both directions would content me.

I had the foams on the wall and directly on the back of a swivel out TV. They got ruined when I removed to paint. They certainly help. There also good for "fine tuning". Some people say there junk and don't do anything. O'well maybe not, maybe they have cabbage in their ears who knows.
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Corners, middle longest wall is where bass is issue.
If a boomy room.

Or ceiling and first reflection , rear reflection on wall is if a room echoes to much.

either fill the wall with foam for absorption . or make checker board for combination.
otherwise drapes and carpet.

Ceiling is usually ignored, but same thing either fill or checker board.
more absorption fill the area, diffraction and absorption checker board.

easy remedy corners, fill with foam cover with drape to look pretty.
rear wall checker board. floor = carpet, Ceiling = carpet or checker board
longest walls absorption in middle, hang drape to look pretty.

or like many common cinder block/ concrete construction movie theatres.
Floor carpet is one color, basic loop/weave or berber office carpet. extend the color
to chair rail height on the wall. Rest of the wall covered in dark berber carpet
or classic heavy red drapes. all done
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I didn't forget dressing the ceiling or floor whenever it can use some. Using the same mirror technic as when dressing the side walls. If you can see the speaker up there, its a reflection point.

JUst take care not to over do things. I once removed a large area rug front centre that I thought was doing positive things. At a point it got too dull. Removing it for cleaning livened everything up in a big and welcome way so it went in storage.

I'm happy with the bass, and its levels I like it at. The room doesn't get boomy. My subs are sealed and PR but I had good sq with reflex boxes in the past also. Granted I still prefer sealed boxes for there tonality.

At a point if not careful it can turn into a game of chasing your own tail. I played that one already.

It still needs help no doubt. The image is badly smeared with volume and some types of music, for instance Tool and vintage Metallica.
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It is a undiscovered method to analyze room behavior with the crunch of vintage
Metallica Creeping Death. LOL !!

My front room had a weird ping pong I could hear from the surrounds on longest wall.
I just hung a blanket in the middle and did a artsy fartsy way of making it hang poofy and
cool starting at the ceiling . And the reflection I heard went away.

a usually straight drape the corners then add another poofy hanging drape in the middle.
adding led lights is more important of course for sound quality LOL.

But basic carpets and drapes work well for rooms. extreme examples use the foam
then hide with drapes.
Exactly you dont want things too dead. and excessive absorption only needed in certain areas
old rehearsal rooms were completely covered in carpet and too dead.
But otherwise a good example how much of extreme change basic material achieve
and not 5 to 10 grand worth of magic thingy's.
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I'm going to add software. Room overhaul not quite there yet.

Instead of one panel per speaker I'm doubling them up (main longest wall.

Not top shabby. Last and final step the textiles.
Then I'll get to the large one. And may do another skyline since there easy and effectiv3.


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Yep,after a fibrous read. I may go two ply and run a filter. Got to think of others health.

Always planned to cover though. Its not a full on man cave:( thinking of a large black knit. To contrast New paint and the tint of the oil. The designer in me is just screaming to get out lol.
I purchased a king sized bedding textile. Double ply with thin cotton membrane.
Think this ok okay for absorption and filtration?
As importantly keeping the rw from air birth. I mean it should be ok its not like ppl will be wrestling on them or anything👌


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It should be ok.
You use Rockwool not glasswool so fibers are coarser.
If you still have concern try this material, it's pretty effective to create an RFZ ( but not as cheap as RW) and doesn't introduce health hazard:

Why have you made the frame closed back?
A way to increase panel efficiency is to only have a frame to hold absorbing material ( keeping front and back open) and to use a bit of distance between panel and wall ( in the 10cm range): it extend efficiency in freq down a bit.
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I closed the back because space concerns. Thinking ill mount them tight to the wall. I believe your right to say open backs away from wall adds to there effectiveness.

I have plenty of rw and will be experimenting with a couple different design ideas. Including some portable open back panels on stands.
I made the same kind of panels out of 1x4’s and rockwool. I used ceiling panels for the backs instead of plywood or pegboard. I went to the fabric store and bought some cheap but not too offensive fabric to cover them with. I made a couple of them 24x48” and some others 16x24” and 12x24” I placed the large ones on the front wall, mediums on the side wall and back wall. I haven’t really used the small ones, they are absorbing sound in the closet. The absorbers did make a difference in the treble and upper midrange. I need to work on some diffusers for the midrange. The large panels cover down into the midrange if I have them set off the wall 4” or so. You can get the same effect simply by making more and placing them at various depths - a skyline absorber? I hear skyline absorbers work best with LED lighting 😉

I have had zero results with foam. It simply doesn’t work. Newer foam may be better though. I stick with the materials used in the olden days; fiberglas, rockwool, and real wool from fur bearing critters.
I think your idea with the slats in front or over the rockwool is a great idea. That should lower the absorption frequency and may keep the top end from going dull. I don’t know of any math to help figure this out, so you may be on your own to experiment. I’ve seen many commercial products with what appear as 1/4” routed holes in birch plywood. Also, the mass, stiffness, and width of the slats would change the damping characteristics too. I need to try this.
I like that idea and will try to execute it as soon as I come up with a way to upolster them leaving the frames exposed and keep the fabric tight in the process.

I might pick up a can of tack aerosol and wrap them up like a pillow case. But that would require thin foams on one or both sides in order to stick to.

In rooms that perform double duty or main use weather slats do a little or alot in terms of acoustics, slats with nice veneer will really dress them up, in a subtle or bold way depending how crazy you wish to go.

A solid ice white or a type of white wash with grain showing through. High waf factor. I agree that would look good.

I'll get the first three hung tomorrow. I'm just happy to have motivation to complete projects back.
Slow progress. But an obvious improvement. Even though bass resonance control is less than dire I decided Ill make a deep 10"x1 / 2" panel for sidewall immediately under medium sized window, or 2 with close to same dimensions for ceiling, suspended by cables / eye loops.


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