Acoustic Isolation - This has to be a brilliant idea

[ajay_m]

https://www.msn.com/en-gb/money/technol ... c2dd&ei=19

You'd think something like this would already be available, but it seems like a brilliant way of securing plasterboard if it means that the panel can vibrate without conducting sound through to the support frame.

[Drew Stephenson]

A de-coupling screw. Interesting. Would like to see some real world data on it of course.

[tea for two]

"Håkan Wernersson from the Department of Materials Science and Applied Mathematics at Malmö University, together with his team,"
Brings some reassurance as it is from a University research.

It's at beta testing stage I guess.
"Wernersson and his collaborator, Raimo Issalem, are seeking more companies willing to test the product on a larger scale. Conducting more pilot projects will allow them to verify how the screws perform in everyday use and identify potential areas for improvement."

Similar although different screws with spring have been included with cpu heatsinks I've had.
https://myheatsinks.com/products/heat-sink-attachment/

[ajay_m]

It probably is patentable given the novelty of the application. If it is possible to easily mount plasterboard in a way that allows it to vibrate independently of the subframe, that could be very very useful.

I'm not sure about weight though. The mounted panels exert a downforce on any fasteners, so if you want the panel to be able to move laterally that's easy if it's mounted in the ceiling (or floor) but walls are trickier, since the panels will push downward on the fasteners. I imagine that's a solvable problem especially if you keep each panel relatively small, but then in that case you might conceivably just have backed each one with foam or something and glued that to the outer wall. But if you can attach a panel by just a small number of mounting points and still allow it to vibrate freely, the coupling is likely to be a lot less than any other solution. And much simpler to install.

[Hugh Robjohns]

Hmmm.... what happens if the house owner fits shelves or other heavy things to the plasterboard wall? Or screws through to the studding behind?

[alexis]

Laboratory tests have shown that the invention can reduce noise by 9 decibels, effectively halving the recorded sound compared to standard screws.

?

[ajay_m]

I can sort of see a contraption that used a teflon washer as the load-bearing surface (say 5mm thick or so) using a central stainless steel 5mm shaft. That ought to bear load but also be low friction coefficient. I'm assuming that a small number of vibration coupling points will still be acoustically a lot better than a whole vibrating panel directly coupling to the exterior wall in this situation.

You'd have an external part of the contraption (probably made from plastic) that you then attach the plasterboard with, so that it ends up supported by these shafts but free to vibrate (with springs behind each teflon washer) and I could see how you could put a stop on the shaft to effectively 'clip' the external fastener onto it so you can't inadvertently pull the panel off accidentally. The load is then taken by the shaft and washer on one side, and then the washer is a push fit into a shell which is part of the front fastener assembly. So when assembled correctly the panel is free to vibrate but the gravitational load is borne by the shaft and teflon washer. I wouldn't be fitting shelves to this though!

Good question of course is whether lighter panel materials might make more sense (rather than plasterboard). I'm not sure about the physics here in terms of bass transmission in particular. If we assume you are decoupling any bass drivers from the floor (which seems wise) via some kind of compliant vibration absorbing mounts) then radiated bass energy which hits those walls causes panel vibration. If the panels are relatively lightweight but free to vibrate, does this in fact absorb significant amounts of acoustic energy, or is panel mass also important?. If so, what's the 'sweet spot' I wonder?. Never really thought about this before, but it's certainly fascinating. I know that professional studios have isolated floating floors and super-heavy doors and all that sort of thing, of course.

[James Perrett]

I haven't bothered to read the article because it sounds like someone has just invented resilient channel - which has been a soundproofing tool for many years.

9dB attenuation is virtually nothing!

[Drew Stephenson]

For serious work a resilient channel is going to do a better job, and for general work I think Hugh's queries are going to be important.

I still think it's an interesting idea, but I'm not sure it's actually very practical. Possibly some mileage in commercial buildings where there tends to be much tighter controls on what can be done with walls.

[Jorge]

To effectively isolate wall movement in the horizontal direction from the studs, the wallboard would have to be able to move freely along the axis of the screw. Since the weight of the wallboard acts in the vertical direction, there will be friction impeding the free motion of the wall/spring unit along that horizontal axis. This friction both dampens the horizontal oscillation and partially transmits it to the studs, and hanging things on the wall would change that frictional force. You are essentially setting up a simple harmonic oscillator system with an oscillating mass, a spring and a damper and you would have to "tune" the spring constant, the mass and the frictional damping forces to target the frequencies you want to attenuate most effectively.
The resilient channel has solved these issues over the years mostly by trial and error and it works reasonably well. Yes, this is thinner, and it may be worth the R&D effort to perfect it, but scientifically it seems to be in an early preliminary stage. Agreed 9 dB attenuation of transmission is not a lot, but that could theoretically be increased substantially for a given set of frequencies.

[Eddy Deegan]

Part of me thinks that the cumulative effect of using these in place of plasterboard screws throughout an entire building should have some benficial effect. Then again in reality it'll be what Hugh brought up combined with a bunch of shortcuts by builders and the elusive "hmm, doesn't seem to work as well as we'd hoped" factor.

I employed a variety of techniques in my studio build and based on informal tests with my neighbours I found Genie Clips to be the best in terms of isolation.

My studio is not soundproof in the strict sense but it's a space you can make loud noises in without annoying anyone outside it in any direction, even at night, and I'm content with that

[ajay_m]

That was fascinating. I know very little about acoustic isolation and hadn't a clue what a resilient channel is. There's a great link here https://sonopan.com/10-things-to-know-a ... t-channel/
And it seems there is a product called quiet rock which is apparently a layered board which can just be fitted instead of or even over standard drywall and is much simpler than resilient channel installation in terms of accidentally compromising isolation by incorrect installs.
Or so they say. Still I learned a lot reading this thread.

[Dynamic Mike]

When we moved last year the vestibule (roughly a 2.5m cube) was just bare brick painted white. Given it had 2 internal & 2 external walls, the external walls were prone to condensation & mouldy, not helped by the fact that there was no radiator. It looked a mess as the walls were pock marked with repairs from previous shelves/pictures & the ceiling had non-matching 'creative' Artex repairs.

So prior to fitting a radiator we had it plastered with insulated plasterboard. The new ceiling was screwed to batons, but the insulated plasterboard for the walls was attached with a thick grab adhesive of some kind bonded to the insulation layer. I guess from this that it's effectively decoupled the plasterboard from the wall as no other fixings were required. I'm not sure if this would be suitable for acoustic plasterboard though as I think that's much heavier than the standard insulated stuff.

It's currently also 100% decoupled from the floor given that I haven't got around to fitting the skirting boards yet!