[Shockabuku]

Hi @. I'm planning the build of my dedicated hc room, on the upper floor of a detached barn. The floor is suspended timber, and the main joists have bowed quite dramatically over the centuries due to heavy agricultural use. To level it out, I'm proposing to build a floating floor over the top. My research has uncovered a product called a stud/beam isolator, as per this link, which looks like it might be beneficial in my scenario. Just wondering if anyone has any experience of these isolators, and whether a whole load of these (I would need a lot!) would be money well spent..? Cheers. Mark.

[dj-dulux]

Hi Shockabuku, I would be very reluctant to fit items like this unless you are likely to have a serious noise issue (serious means that a noise abatement order may be served). And then only with some expert help, they are very difficult to fit correctly and will add significant cost as the builder won’t like them, you may also get issues from building regs (need to check).

In principle they look simple, in practice other flanking paths are likely to degrade there performance to a point which will make you wonder why you bothered! I would focus on putting in a good solid floor with rockwool insulation between, double plaster the ceiling below for extra isolation.

Stick to simple methods if you can……

Dupe…

[Shockabuku]

Hey, thanks again Dupe. There shouldn't be any major noise issues, I was just thinking about isolation from the existing floor, but keeping it simple definitely appeals to me! Cheers.

[Shockabuku]

Had another thought (look out!). I'm toying with the idea of building a stage for the speakers & screen, which would usually, in the case of a ground floor cinema room, be filled with sand, lots of sand. I don't think this would be a clever idea for a suspended wood floor like this, so I'm wondering whether the stud isolators might be the solution in this case...or, should I ditch the idea of a stage as it really does need the mass of all that sand to make it acoustically acceptable..?

[dj-dulux]

Shockabuku, sounds like your project is growing and you have a pretty clear idea what you want, this is very good!

Filling the speaker support system can be filled with sand or concrete and there are good reasons for this. Basically the purpose is to prevent the support system from radiating unwanted noise; this is the same principle of filling speaker stands with sand. If you don’t and the stand has an radiating area you will colour the sound with additional noise radiated from the stand (hope this reads OK and makes sense?). This covers the frequencies above around 200Hz, the other reason is to produce an acoustic mirror to produce a true boundary to increase the efficiency of subwoofers. Its unlikely that you will be able to achieve a true mirror, but making walls as solid as practical will help.

So really, as always it’s a compromise.

Instead of stopping the speaker support system radiating another option is to reduce the radiating area of the support system and isolate the speakers from it. This is much more practical in a domestic environment and allows for a bass trap made from foam to be fitted in the same support system. See the pics below. This is just 2"*2" timber and the speakers sit on 4mm ribbed rubber sheet, the timber around the speaker is also well rounded to prevent edge diffraction effects.

Coming to the stage, build it solidly, 25mm top and well glued and screwed. Fill the cavity with rockwool, this will prevent any problems. If the stage is several tiers high you could leave the front of the steps open (lots of 100mm holes drilled) to act as a further absorber within the room.

Dupe…

[Shockabuku]

Thanks again, Dupe, useful information. I'll just call you my own personal home cinema consultant if I may . I'm not 100% sure I have the drop available for a stage (considering the position of the beam on which I intend to hang the screen, and that I'll already be raising the whole floor), but I hope I can manage something. Actually the biggest issue in the design right now is that I need to maintain access to what will be my home office, behind the screen area, which pretty much rules out a fixed screen. Still, not a bad "problem" to have really .