Audiophile drywall screws?

[cochlea]

Just saw this article on gizmodo concerning these new drywall screws that turn drywall into sound-absorbing panels. A new trend to follow?

 

[MakeMineVinyl]

The effectiveness of these would be less at lower frequencies, such as the subwoofer of your neighbor, so I wonder how applicable these actually are.

 

[cochlea]

I wonder though, if they might make a difference to your own listening experience. People spend a lot of money buying and installing sound- dampening panels. Would these make a cheaper alternative?

 

[aedagnino]

According to the graph in the link it's good from 250hz up (-9db), so I'd say it's an awesome product por potentially peanuts.

 

[tmtomh]

According to the graph in the link it's good from 250hz up (-9db), so I'd say it's an awesome product por potentially peanuts.

Yes, I'd say this could be an excellent product - and not only is it super-cheap, but it also doesn't require specialized installation or extra labor time, which is a key factor in keeping the total real-world cost minimal.

By separating the drywall from the studs, these screws basically function the same way as a hanging/spacer wall, a common sound-treatment technique in which the drywall is hung on metal brackets connected to the studs, thereby acting as spacers between drywall and studs.

These screws make less space than those brackets, and therefore provide less of a potentially sound-dampening air gap - but at the same time the surface area of each screw's connection is much, much smaller than that of the metal bracketing of a spacer wall, so the points of direct transmission from drywall to stud would presumably be minimized by using these screws.

I'm a little dubious about the springs - I have my doubts that they really damp the vibrations of the drywall, and I would guess that it's the spacer effect rather than the spring effect that does the most good. But the springs certainly can't hurt, and when it comes to sound dampening and isolation, every extra dB you can achieve with a combination of insulation, treatments, etc. is worth it.

 

[MaxRockbin]

It would have been nice if they showed a picture of the screw actually in use. Here's what a normal drywall screw looks like:

Here's what the fancy spring screw looks like. With regular drywall screws, you screw them through the drywall and into the stud. The head of the screw and the threads hold the drywall to the stud. With these things, the top of the screw with the spring has a much larger diameter than the threaded part. It looks like you would need to predrill the drywall for that diameter. The head is only slightly larger - if at all. So what's holding the drywall? It definitely doesn't appear that you could just use these as simply as ordinary drywall screws, as the article states.
If they're practical and they work, I think their biggest claimed advantage vs the resilient channel style brackets is that they don't require the drywall to be spaced much from the studs. So that makes retrofits much easier and takes away less space in the room.

 

[egellings]

You gots to be kidding!

 

[cochlea]

Just saw this on another website. It helps explain a little better how they are installed:

“The screw is inserted into a hole drilled through a drywall panel and into the underlying wooden stud. It is then turned until its threaded section is all the way into the woodj, and its head is sitting flush against the outside surface of the drywall. The spring forms of a gap of a few millimeters between the stud and the drywall's underside.”

 

[egellings]

I 'spoze.

 

[scott wurcer]

So what's holding the drywall? It definitely doesn't appear that you could just use these as simply as ordinary drywall screws, as the article states.

It looks like the outer head is threaded as well as being slightly larger. If you don't use a drywall gun it is very easy to shoot the screw right through the dry wall. I expect the installation does just that using the auto stop feature to set the second head right at the surface. I wonder what they do for the edges joints that are thinned down on standard sheets so you can make a clean joint.

 

[_thelaughingman]

That screw has so much sound isolating cred!

 

[MaxRockbin]

Egellings - you have to figure in that soundproof (resistant?) drywall is a pretty standard thing. Universal for studios, but also routinely used in apartment buildings and anywhere you don't want to hear your neighbors. The idea is pretty much always to create an acoustic break between the outside and the inside. A typical strategy is to attach the drywall by a thin metal bracket so most vibration is forced to travel over a narrow bridge. Only so much energy will traverse a little metal bracket (aka resilient channel). So - less sound. I guess speaker spikes work on a similar principal, though probably with less need or impact. Sometimes laminated drywall is used - with an elastic goo between the layers. But that's more expensive and arguably less effective.

 

[Cbdb2]

According to the graph in the link it's good from 250hz up (-9db), so I'd say it's an awesome product por potentially peanuts.

But almost all the leakage, what you hear on the other side of the wall, is below 250 hz. And the low stuff needs mass to stop it.

Drywall on springs will vibrate more, which will decrease the sound transition but it might cause audible resonances from the drywall in the listening room.

With hundreds of drywall screws in a room the cost can't be too high.

A party wall is still the best solution, after brick/concrete.

 

[MaxRockbin]

[

Just saw this on another website. It helps explain a little better how they are installed:
The spring forms of a gap of a few millimeters between the stud and the drywall's underside.”

If you need that gap - it would rule out retrofitting - at least without stripping off the existing drywall. You couldn't just remove the old screws and put in new ones.

 

[egellings]

It seems to me (I'm no expert here) that mounting drywall so it is decoupled from the house framework means that it is freer to vibrate at low frequencies and then, due to the low damping, re-radiate it, causing LF peaks or dips in the room. Does that make any sense?

 

[Cbdb2]

Egellings - you have to figure in that soundproof (resistant?) drywall is a pretty standard thing. Universal for studios, but also routinely used in apartment buildings and anywhere you don't want to hear your neighbors. The idea is pretty much always to create an acoustic break between the outside and the inside. A typical strategy is to attach the drywall by a thin metal bracket so most vibration is forced to travel over a narrow bridge. Only so much energy will traverse a little metal bracket (aka resilient channel). So - less sound. I guess speaker spikes work on a similar principal, though probably with less need or impact. Sometimes laminated drywall is used - with an elastic goo between the layers. But that's more expensive and arguably less effective.

Yes drywall is standard but theres a few things to remember. The heavier the better. Don't use the light stuff, use at least 5/8" And a different thihkness on the other side like 1/2" (this gives the 2 walls different resonant freqs.). Use the heaviest insulation you can find (the acoustic rockwool is 4 times heavier than fiberglass) between the walls. Use the hangers or those new screws. And if your really worried, 2 sets of studs (a party wall) with a gap cut in the floor between them.(sound will travel thru the floor and cieling). And if you've gone to these lengths youve wasted your time unless you deal with the doors and windows. Which are more complicated and expensive than the walls. And
don't forget your air ducts!

 

[MaxRockbin]

And if you've gone to these lengths youve wasted your time unless you deal with the doors and windows

Just an aside about windows: Most people don't know this but when you order windows - like, say, double pane windows to replace those old classy looking single pane, you can spec thicker glass - usually for not much more money. Also you can spec that the inside and the outside have different glass thickness. That helps reduce noise transmission too. Laminated glass is awesome. I was surprised how much difference it makes and thumbs up for anyone with noisy neighbors (or if you don't want to be one). Resonances, damping, air volumes... Windows and speaker boxes have the same issues.

 

[BlackTalon]

I can't wait to see the double-blind testing setup to check the effectiveness of these screws

 

[scott wurcer]

Which are more complicated and expensive than the walls.

Around here these days increasing the thickness of the walls 3" for a 10'x20' room will lose you $15,000 in value.

 

[Cbdb2]

Just an aside about windows: Most people don't know this but when you order windows - like, say, double pane windows to replace those old classy looking single pane, you can spec thicker glass - usually for not much more money. Also you can spec that the inside and the outside have different glass thickness. That helps reduce noise transmission too. Laminated glass is awesome. I was surprised how much difference it makes and thumbs up for anyone with noisy neighbors (or if you don't want to be one). Resonances, damping, air volumes... Windows and speaker boxes have the same issues.

3 examples of studio windows at the bottom of this page.

https://www.acousticalsurfaces.com/acoustic_windows/acoustical_windows.htm