Experiment question about sound treatment project

@goose Agreed, but he seems to have access to materials. I am not going to do things that way but it's interesting to see the concept he's deploying.

Hmm, I would imagine that the frame material in rixthetricks system would cost as much as several finished panels from acoustimac which I have used in my room.

@rix Nice photos and system. Interesting solution. Question: does the frame vibrate and does the fact that the rug doesn't go all the way behind each speaker matter?

@hilde45 I purchased a large thick woolen rug from an estate sale.
As I work in the Texan oilfields I often build racks using double uni-strut.
This along with spring nuts and some L and T shaped plates bolted up nicely to make a frame which I draped the heavy rug over.

On the frame there is a five inch gap between the front layer, and the rear layer, and then a three inch gap from the rear layer to the wall.
Sound has to pass through two layers before it bounces off the wall and back through the two layers to get back to me.

I am building four QRD17 quadratic diffusers, two will go on the inside of the frame held about three inches above the floor (under them will be cabling etc tucked away, with generous arcs to allow air between them and suspension system to elevate cabling). And another two QRD17 outside to play with positioning.

Wool, believe it or not, with air gaps and layering is surprisingly good. The distance away from the wall made a difference. To give some idea of scale, there's 8.5 feet between tweeters on my stand mount speakers (last photo).

https://systems.audiogon.com/systems/8721

Comment from earlier, edited.

Thanks Tvad. That might be a happy middle ground.

MC -- very much in line with your thinking. Small steps, paying attention, learning, doing, making -- that adds up to genuine knowledge. I am not against the idea of eventually paying for something pre-made or even expensive. But I'd like to conclude with some justification that these things are worth it, and if I don't learn to get there (listening the whole while) I'll just be throwing money and praying for a sonic payoff.

Turnbowm -- good ideas! Why not try lots of things, all the while listening, changing, noting the difference! Thanks!

"To avoid the trouble of making the panels and finding out they don't help, could I simply hang pieces of the inner absorbent material to test out possible pact?"

Sounds like a good plan. I did the same thing except I didn't have any panels so I used folded beach towels to determine what was needed and then ordered the panels.  

By the way, as far as frames go- and skill- not even necessary. Mine are nothing more than OC703 cut and wrapped in fabric. The fabric is simply wrapped around and held together on the back with pins. Same way women pinned fabric before sewing, back in the days when even women knew how to make stuff. Mine are stapled to the wall. Easy, fast, and cheap. KISS!

The best way to learn is by doing. Frankly it is the only way. Because even when you buy something, and even if you pay a consultant to design and build, still you really only learn once its done and you have something to listen to. Everything up until then is talk. Blather.

It costs like ten bucks to buy one panel of OC703 from a hardware store. Cut in half with any reasonably sharp utensil you now have two acoustic panels each one light as a feather and yet totally effective for testing purposes.

Be interesting some time to take a poll find out who has actually done and knows and who is all talk. But that would sting more than a few. Heck they are triggered at the mere thought of it. What you do though, take your small 2x1.5ft panel, hold it up to the wall. Don’t even stick it on the wall just hold it there at arms length. Talk. Listen. Hear the profound difference with and without the panel. And I do mean profound.

That one little sheet, those two little panels, more than enough to treat something like say first reflection. So try them there next and see what you hear. Total cost time and labor and cash: $10/1hr. Total DIY construction skills required: cut one straight line with a knife. 

This is not even to say cover that panel and call it good. Its called an experiment. A try and see. If it works great, great. Cut it down. See how small a panel you can get away with. Even if you do decide to order expensive GIK at least you now know how small it can be, and have a benchmark against which to compare performance.

Again, be real interesting to take a poll, find out who knows, and who only talks like they know. On that score, in case you don’t know, all you have to do is click on a posters name to get a link to their system page. A lot of them are blank. We even had one guy here never did have a system. All hat. No cattle. Gone now. Good riddance. One down....

Thanks, dsper! My plan is to do a lot of sound measuring FIRST and perhaps try to have a conversation with GIK or others to see what my level of need is. If I need a lot of help, I may bite the bullet and buy. If I just need a little help, DIY may be the way to go.

I have the same level of skills that you do. The key, for me, is to be in the right "zen" frame of mind, because I am a word person not a physical making person, and I can get easily aggravated if I try to do a DIY project quickly.

I've used blankets, pillows and raw absorbing material to test.

DIY is a lot less expensive, but purchasing completed panels will look more finished depending on your skill level.

Do some homework before you move ahead. Learn about sound absorbing properties of various materials so you avoid buying junk. This applies to purchased and DIY.

I have a man cave and did DIY. Looks good but would not meet WAF in our living/family rooms.  

Both Roxal and Owens Corning make the absorbing material.

Joann Fabrics for the covering material.

Home Depot will cut your wood frame pieces for free once you have your measurements.

FWIW; my skills are the ability to measure, drill holes, drive screws, use glue, and pound nails. I can hang wall paper, curtain rods, and pictures, replace plumbing fixtures, and have taken apart a clothes dryer and dishwasher to make repairs.

It took me about one and half to two hours to build one complete 2ft by 4ft panel.  

https://fullenglish.co/blog/2016/8/13/sound-absorber

Thanks for listening!

Dsper

Thanks, Mesch. ATS is much more affordable. I'll check them out, and the Roxul parts, too. Amazon has this but the shipping price is crazy. I need to find someone else, locally.

Thanks ebm. Helpful suggestions.

I purchased Roxul Rockboard  60 2", 2'x4' sheets, and made my own panels. Likely can find that locally. 

Might want to check out ATS Acoustics. they sell factory made panels and supplies for DIY. You can send them pictures and have them put on to fabric for decorative panels. Vey helpful people. Have a nice website.

@ebm Are you saying it's not worth doing the experiment above? That I should just go straight to buying expensive panels? Can you say more why?

Thanks, MC. I don't think I had a link to that older webpage and I appreciate getting your reading list. Some reading to do!

I also appreciate seeing the ceiling and corner treatments. I don't have a dedicated listening room, so I probably won't go to the lengths you did until I do. Still, they're good reminders that reflections can and do come from anywhere.

Your plan is exactly what I did and still recommend. Owens Corning 703 acoustic panel is practically an industry standard, and widely available in 2'x3' sheets 1" to 3" or thicker. The thicker you go the lower the frequency, with 1" being fine for midrange-treble we usually want to get the most. It cuts easily and its so light weight you can pin or tape temporarily to test. The corner tunes in my room are OC703 covered with fabric. https://systems.audiogon.com/systems/8367 Test panels in raw form from 2004. https://theanalogdept.com/c_miller.htm

Good suggestions! I'm looking forward to just digging into the project. 

Oh, not just that, but blankets and pillows also work the same way.

What I do believe is that you need a certain minimum critical mass.  You can't take 2 panels and hope to hear much. If you experiment, start out with 6 or more blankets/panels. :)

And don't forget the floor behind/between speakers.

Best,
Erik