Room treatment materials in Aus??

[Hakka]

I have been doing a bit of research on that materials used to acoustically treat HT rooms, most of the products that are used don't seem to be available in Australia.
Now that there's quite a few Aussies on this forum, what materials do you use and where did you get them from??

The only things I've been able to find here are products made specifically for room treatment, only problem is they cost a fortune.

Thanks.

Harry.

[Alan Brown]

You should be able to find rigid fiberglass "duct board" from heating and ventilation suppliers. It is typically 2 foot x 4 foot x 1 and/or 2 inches thick. Here in the US, we find it in 2 densities. The higher density is better.

One variety is black and treated to prevent the glass fibers from going airborn in a high velocity air duct. Another variety is untreated. The untreated is best because the pores are not blocked and absorbs sound better.

Cover this board material with acoustically transparent fabric. Here, it's called "panel fabric" because it's used for covering office cubicle partitions or panels.

[Prof.]

Hakka,

I found this article some time ago on making your own acoustic panels, using fibreglass duct board..
It's something that I'm looking at doing also for both bass traps and wall treatment..
It should be available from Air-conditioning Installers..
Hope it helps..
http://mywebpages.comcast.net/kidder/Audio/Room/PANEL/Panels.htm

[Hakka]

Thanks for the info, I rang a few local air con suppliers to see what was available. I mentioned 'acoustic panels' to one bloke and he told me exactly what I need. Going to pick them up now I'll let you know how it goes.

Harry.

[Hakka]

There were 2 densities available and two thicknesses 25mm and 50mm. I went for the high density 25mm. One side has a peforated foil covering, the other side is bare. The salesman said the perforated side is the sound absorbing side. I hope the foil doesn't reflect light back through the material.
I have a pic on my phone but for some reason I can't email it to my PC. I will attach the pic tomorrow.

While we were there he had a metal duct, approx 1.5m long, with a 25cm square opening at each end. The duct was lined on all sides with the high density 50mm duct board. He put his head in one end and I put mine in the other, when he spoke I could barely hear him, it was like the volume had been turned way down. I was very suprised at how effective this stuff is at absorbing sound.

[Prof.]

Is the material called "Duct Board" or do we know it by another name?
Also what size sheets does in come in?
I'll be very interested to hear how it works out for you..

[Hakka]

Yes, it is called duct board, the sheets size is 1200mm x 2400mm, cost $40 per sheet. It is available in 2 thicknesses (25mm, 50mm) and 2 densities. It has a foil backing on one side, the foil can be perforated or non perforated, I dont think it will matter which one you get.

I was advised to have the foil side facing out but after googling 'acoustic panels' I decided to go the other way.

I made 2 panels about 1m square, I just cut the duct board to size and wrapped it in material. I am planning to make 3 panels 1200mm x 2400mm, these will be mounted in wooden frames, I will place one on the front wall and one on each sidewall. This should cover all first reflection points for the front speakers.

[Prof.]

Thanks for that info....$40.00 for 1200x2400 a sheet sounds fairly reasonable...

He shows (on that link I posted) the foil side as the back of the panel, and I've also seen it used as bass trap in the same way, so I guess this is how it should be used..

Making acoustic side panels using a full sheet at the first reflection point seems a bit excessive...unless you have a very "live" room..

One sheet cut in half down the length, and the two pieces placed on top of each other, should make a very good bass trap, and I think this is what I will try first..when I've found a local supplier...

Did you notice any improvement with the test panels?

[Hakka]

Prof. wrote:

Making acoustic side panels using a full sheet at the first reflection point seems a bit excessive...unless you have a very "live" room.

I've done a bit of research and I found the general consensus for room treatment(absorbtion) is to treat the side walls from the ground to just above ear level and to treat the entire front wall (leave the backwall bare). The majority of my front wall is covered by the screen so I will just treat it up to the bottom edge of my screen, which is about 4 inches above my tweeters and ears.

My room is solid brick, with the sidewalls rendered, there is no flex in the walls like there is with plaster.

I think it would be a lot harder to make these with the foil side facing out, it is a lot easier to attach the material to the foil side than the uncovered side.

I *think* the system sounded better with the panels in place on the side walls but I didn't AB test it. There seems to be more detail in the high frequencies than before, also the soundstage seems bigger.

[Prof.]

Hakka wrote:

I *think* the system sounded better with the panels in place on the side walls but I didn't AB test it. There seems to be more detail in the high frequencies than before, also the soundstage seems bigger.

That sounds good (no pun intended) that you can discern some improvement with those metre square panels..
I have a good soundstage but I do get some blurring in the mid highs. Hopefully this material will improve that...

Looking forward to hearing your results when you've made your panels..