[mresseguie]

I visited an audiophile friend a few days ago. This guy is very much into tweaks of every kind. One thing I asked about was his hanging a very thin woven nylon-like material on the back wall directly behind the listening sofa. [Imagine a flag to get an idea of its thickness.] The guy insisted it was effective at absorbing some high frequency sound. I professed incredulity. He insisted he was correct. [He often insists his tweaks do this or that, and one had better be prepared for a knock down drag out argument if one wishes to disagree with him.]

Thoughts? Opinions?

[Tyson]

Well it's better than a bare wall, but just barely. 

[FullRangeMan]

I have seen many eggs boxes in a garage studio wall, it dont work either, also shaggy rug dont damp to my ears, I have used 5mm black felt to some effect.

[mresseguie]

Agreed. It is better than bare wall - especially considering walls here are six-inch thick concrete. One of these days I'll catalog all of his tweaks. There are plenty.

[jtcf]

If there's a little bit of air space behind it, then it would have a small effect on the very highest frequencies. But only with reflections, it wouldn't damp anything.

[mresseguie]

In your experience (anyone), would you say an inch of fairly lightweight foam is superior to two inches of rock wool?

[Letitroll98]

In your experience (anyone), would you say an inch of fairly lightweight foam is superior to two inches of rock wool?

No, not even close.  And I've used both.  4" of rock wool is very effective.  I have some heavy looking foam panels saved in my Amazon cart, very cheap, that have grandiose claims.  I don't think I'll ever pull the trigger, but I was curious enough to hit the save button.

[JLM]

Can't judge absorption material by description or appearance, must be measured across a wide frequency range.  Hard to find such measurements.  Doubt that thin fabric would make any perceivable difference.

[mresseguie]

No, not even close.  And I've used both.  4" of rock wool is very effective.  I have some heavy looking foam panels saved in my Amazon cart, very cheap, that have grandiose claims.  I don't think I'll ever pull the trigger, but I was curious enough to hit the save button.

The reason I asked concerning foam vs rockwool is because I told this tweaker (not to be confused with a trweker) that I finally got permission from my wife to put some absorption panels on the front and back walls. Rather than buying premade panels, I want to make my own using 4' x 2' x 2" roxul slices mounted on/in thin frames and covered in a fabric that my wife finds pleasing. The above mention guy told me that was unnecessary, and that I should just get 2'x2'x1" acoustic foam panels like he has. I insisted that I wanted better absorption, but he claimed foam is just as good. I stood my ground, so he recommended I buy premade GIK panels. Well, the GIK panels are about $50 each while 6 sheets of Roxul are essentially the same price. Hmm. Let's do the math. I buy Roxul, wood slats, glue and nails and inexpensive cloth....the total might come to $150(?) and I'll have six panels or four regular panels and four 2'x2' panels vs three GIK panels for $150. Hmm. Hmm. I've made these panels before, so I know how to do it.

My biggest question is why are the GIK panels so cheap compared to what they cost in the US?

[Letitroll98]

Wow!  $50?  That's insanely cheap.  I must guess, assume, be pretty damn sure they're either knockoff or GIK has them manufactured there.  It can't be too hard to pull a couple staples and check the construction.  And it's also pretty easy to contact them here on AC and ask.

[mresseguie]

Just now, I referred back to the website where I found the ~$50 panels, and that price is no longer offered. I wonder if it was a Black Friday Deal? Dunno. [Yes, there were Black Friday deals here, too.] The prices that are listed now are $3500 NTD ($109 USD). The website is https://dimi.tw/store/product/gikacoustics-spot-panel-rectangle-ej038

I have no reason to think it's not real. With the $109 price per panel, I'm even more convinced the DIY approach is far better. Vicoustic panels are available online, but these are foam boards.

[timind]

Building these absorption panels is a fairly straight forward task if you have the materials, space, and the least bit of skills. I used pieces of 1x4 to build the frame. For me, the most difficult part of the task is applying the fabric as neatly as the pros.

[mresseguie]

Nice to 'see' you! I was going to type that I haven't seen your posts in a long time, but noticed you have been posting. I'm an hour's drive from the best acupuncturist I have ever been 'stabbed' by. Her needles relieve my tinnitus and my hyperacussis, but I have to keep going or they slowly return.

Yeah, the fabric can be a bitch. I'll need a staple gun. I may hire a seamstress here to make me a few extra-large 'pillowcases'. Hmm. I wonder...