Strange room in a strange land...

[mingustoo]

I have just moved my humble music lodge into a new home. I am in the process of setting up and would appreciate your wisened counsel. The room takes up half of the top floor of about a fifty year old house in Taiwan. The floor is plastic 'tiles' covering cement. The sides are: cement along one side wall, a mixture of cement, thin glass and wood sliding door along the front, and cement half wall, windows, and shaped aluminun sheets along the top half of the other side wall. The side walls are approximately 30 feet long. (sorry, the tape measure has gone missing in the move-I will get specific dimensions if needed). The rear of the room lands under the apex of the roof with approx. 10 feet of concrete topped off with six feet of wood, with about a three foot gap at the very top. The roof is angled (obviously) and appears to be some sort of pressboard on the inside. It starts off about 10 feet high in the front and rises to be about 20 feet high at the rear. There are doors in both the rear corners.
It seems to be near impossible to find OC703. The only thing I can get is blank stares. There is something similar to the old fibreglass pink insulation that is pourous and seems to be made out of plastic. It is also possible to get rolls of the insulation they use in cars and under carpets.
I have done searches and followed many threads to the end, but it seems there are people out there that get a kick out of helping a semi-moron like myself maximise his minimal cash and limited knowledge. Also, since I live in Taiwan, I can't just stroll on into the local 'Lowes' (is what keeps getting mentioned) and grab mounds of OC703. they don't know what that is here. But I am willing to explore and try different things out.

Any takers?

[Ethan Winer]

You don't need 703 - there are many equivalent materials. See the second paragraph in the Rigid Fiberglass section of my Acoustics FAQ for a list of alternatives and links to various manufacturers.

--Ethan

[mingustoo]

Thanks Ethan. It's great to have actual experts around setting us straight. By the way, your Telecaster video gave me nightmares. Just kidding!

[mingustoo]

a pic showing some of the front, the right side, and a bit of roof.

[mingustoo]

Here is another terrible photo showing parts of the back, ceiling, left wall. There is another door in the rear right.

[mingustoo]

My wife loves to take the worst photos. But anyway, here is the other half of the front. A Mixture if windows, cement and light panel door.

[mingustoo]

and.... an amazingly awful picture of the rear wall. Note the doors in the rear corners. I guess they should be left open to minimize the bass?

[Ethan Winer]

Originally Posted by mingustoo

By the way, your Telecaster video gave me nightmares. Just kidding!

Heh, when I first put it online a friend of mine emailed me and said, "Too many Ethans!"



--Ethan

[mingustoo]

Oh BTW, maybe you missed it in the text. But I am in Taiwan and there is no Heating , lumber yards, or anything like that. I can get something that LOOKS like rigid fibreglass, but it is a white material that the sellers have no idea where it comes from or how it's made. Worth a go? And when I ask about Owens Corning, they just stare blankly and chew betel nut.
cheers

[Ethan Winer]

Can you get regular fluffy fiberglass? Of so, that can be packed and squeezed to be more like the rigid type. If you squeeze 12 inch fluffy fiberglass down to 3 or 4 inches thick, that will work very well.

--Ethan

[mingustoo]

Ethan , thanks for your input. You are a true 'Acoustic Commando'. But unfortunately, there is no insulating done in Taiwan. The windows don't even seal. So in the summer the locals crank up the a/c and when it's cold, they layer on the sweaters. I'm looking for alternate materials or methods. I guess opening the windows and doors in all the corners will help too.

[Ethan Winer]

Originally Posted by mingustoo

I'm looking for alternate materials or methods.

Wadded up old clothing absorbs pretty well. Not sure how you'd make that look acceptable, but in a pinch it will work. I once tested three large plastic garbage cans filled with random trash, and that actually absorbed bass pretty well. And just so you don't think I'm kidding, below is one of the photos from the test.

--Ethan

[Glenn Kuras]

Originally Posted by Ethan Winer

Wadded up old clothing absorbs pretty well. Not sure how you'd make that look acceptable, but in a pinch it will work. I once tested three large plastic garbage cans filled with random trash, and that actually absorbed bass pretty well. And just so you don't think I'm kidding, below is one of the photos from the test.

--Ethan

Is that a zig zag rapper I see?

Glenn

[Ethan Winer]

I believe it is!

[mingustoo]

Ethan, I put laundry bags full of material and blankets and such in the four front corners but im not sure they helped at all. I also had the agonizing experience of listening to a 'great' mix of mine on someone else's speakers. HORRIFYING! Couldn't sleep that night.
Anyway, I actually managed to find a company that manufactures rockwool in town here (they make or made everything here) so I'm going to go spend all my microphone money on rockwool. Bittersweet that is.
My question is about placement. Front corners are first priority? Next would be the rear wall? or the vast areas of wall on the sides?
I guess I 'learned' what I already believed the hard way- fix the room first! I can't believe how terrible my mix sounded in the other room with the other speakers.
I forgot to put on the sketchup pics that the ceiling is a pressboard under tin or aluminum. Also , it looks in the sketch as though there is a false ceiling, but that is just due to my inexperience at sketchup. The roof is actually the slanted part.
please help!
Oh, and the rollies in Ethan's garbage were probably mine!

[Ethan Winer]

Originally Posted by mingustoo

Front corners are first priority? Next would be the rear wall? or the vast areas of wall on the sides?

Front corners for bass traps, rear corners for bass traps, first reflection points on the side walls and ceiling. They're all important.

Oh, and the rollies in Ethan's garbage were probably mine!

--Ethan

[mingustoo]

Ethan, or whomever decides to chime in...
What about putting them into gobos and positioning them directly behind the monitors as I've seen some people do on this forum? Is there an advantage to that?
Also, the stuff I ordered is 100kg/m3 -the densest they had. It is 120cm*60cm*5cm and I ordered 30 pieces.
thanks again....now where were those rollies?

[mingustoo]

Im part way through making my absorbers and thought i'd check on some issues with you guys. I am making four eight foot by two foot bass traps for the corners of 100kg/cubic metre rockwool 10cm thick. I am also planning to make a bass trap 120 cm by 60 cm by 10cm for the back wall. As well, there will be 12 absorbers of 120 by 60 by 5cm of the same rockwool.
First question: With doors in the rear corners, the basstraps will have to stand out from the corners a ways. Will this hurt their effectiveness if they are a few feet away from either wall?
Question two: How critical is it to treat the upper portion of the side walls? As you can see it's a fairly large room with a slanted ceiling. I'm probably going to double my initial investment in treatment soon anyway, but for now how critical is it?
Question three: Am I way off with my plan?
thanks for any help.

[Ethan Winer]

Originally Posted by mingustoo

With doors in the rear corners, the basstraps will have to stand out from the corners a ways. Will this hurt their effectiveness if they are a few feet away from either wall?

Just put them as close to the corners as you can.

How critical is it to treat the upper portion of the side walls?

With bass trapping, the more you have the better the LF response. So I suggest putting traps in wall-ceiling corners too.

--Ethan