John Sayers' Recording Studio Design Forum Archive

errrr... i was going to say something about that, but then i decided against it.

that's something that might be good OR bad, hard to say without testing IMO.

personally i would button it up more but that's just me ... i have no scientific basis for that.

I realize there are theories of pros and cons of joining all layers of a leaf. A benefit of not joining them is that you have different resonance frequencies, helping isolate mids and highs, whereas a benefit of joining them is that you have a lower overall resonance frequency, helping isolate lows.

And since lows are the hardest to control, I figure that's the name of the game and that in the event of a tie, we should "go for the lows."

At least that's how I understand it. I welcome corrections.

--Keith

I realize there are theories of pros and cons of joining all layers of a leaf.

There are no acousitlcal reasons for wanting layers in a leaf to be separate. If they act separately they are leafs in and by themselves, and can also create rattles.

Andre

My plan is to put more screws in the second layer of drywall and to go through the first layer when I do it using longer screws. Those pieces in the picture are 40" tall so I figured 4 screws would be enough for the first layer and then I'd probably use 6 or 8 for the second layer. I of course will use backing rod and acoustic sealant for each layer.

Is there something really wrong with this plan?

Frank

Thanks for fixing me, Andre. I figured there'd have to be an air gap in order for the layer to become another leaf, and I guess I'm not as clear as I thought I was regarding the concept of a leaf made up of different thickness of materials having some benefits in TL.

bondsong wrote:. . . I of course will use backing rod and acoustic sealant for each layer.

Is there something really wrong with this plan?

That depends on the answer to the question I am asking on my thread about the importance of those steps -- and I see that you are tuned in to see the answer when it comes!

--Keith

Yes I am. I don't think it will affect me doing my first layer of beef-up though, so I'll continue while I wait for the answer.

Frank

"Anyone know where to buy an inexpensive Radio Shack-type SPL meter in the Vancouver, Canada area? "

Come out to Langley, I got mine at the Radio Shack in Willowbrook mall...

So, I won't have to worry too much about fire destroying my whole studio building, since I am insulating the whole place with this stuff.

Won't keep my rack from exploding, but if it does, might keep it from burning the whole place down.

Cool added perk.

maestro_dmc wrote:So, I won't have to worry too much about fire destroying my whole studio building, since I am insulating the whole place with this stuff.

Are you referring to Thermafiber Sound Attenuation Fire Blankets (SAFB) - Nominal Density (2.5 pcf) and Roxul Acoustical Fire Batt (AFB) - ≥2" (2.5 pcf), and Roxul's videos from page 1 of this thread?

Come out to Langley, I got mine at the Radio Shack in Willowbrook mall...

Thanks Jef, I'll check it out.

Frank

Just a quick question.

The accoustic caulk I bought is Mulco Acoutik.

It says on the spec sheet that it must be covered and it cannot be painted.
My question is, on my final layer of drywall how do I cover it?...tape and mud?... some kind of trim?... find some other kind of caulk that can be painted?

Thanks,
Frank

Another question. In the picture below the areas labelled "here" are 2x10s at the top of the basement wall. below them are 2 2x4s and then the wall I've started beefing up with 5/8 in drywall.

My question is; Do I need to beef up the 2x 10 section of the wall as well or should I just make sure it's sealed? I Know I'll be covering it with insulation after the beef up is done but I'd like to know if there's any advantage to adding 5/8 in drywall to it.

Any thoughts?

Thanks Frank

you probably need to beef it up a little. it depends on how thick your outer leaf is going to be elsewhere.

if you are using 3 layers of 5/8 then that's about 2 inches of gypsum, compared to 1 1/2 inches of wood, which besides being not as thick, isn't as dense as gypsum either.

if you are using 2 layers of 5/8, that might be closer to comparable. to find out for sure, check out knightfly's post below for a guide on material density:

http://www.johnlsayers.com/phpBB2/viewt ... =6306#6306

dan

Thanks Dan, and thanks for the link.

I'm using 2 layers of 5/8. So I'll probably do 1 layer on that area. That'll make it a little denser than the other areas but that's fine. I'd rather that, than have it be the weak point.

BTW that's a good looking baby you've got there. Congratulations again.

Frank