Ceiling question

We have now finished our shell, 10meters times 6 times 4 (Heights) 3 layers of glued Gysum and yes it sounds like an empty swimming pool. Would ceiling panels of woodchips and cement with a think underlay of insulation be a workable solution? http://www.traullit.se/en/product/products-2/acoustic/ How thick ceiling would you do? I want a lot of low frequency absorbtion and keep as much floor area free as possible. Then again, it´s nice to have a high celing when the room is done. Any input welcome, so many options so i thought this forum would be the place to consult before diving in! Right now our plan is to start with ceiling and floor and see what we have when all furniture and gear have been moved in. The aim is a single room for tracking and mixing. /Thanks /Toby

3 layers of glued Gysum

What do you mean by "glued"? If you mean "Green Glue", then that's fine. But id you mean typical construction glue, that is very much NOT so fine.... You should not glue the layers of drywall together.

Would ceiling panels of woodchips and cement with a think underlay of insulation be a workable solution?

Workable for what? Is that for the outer leaf, or inner leaf? But that product does not look like it is any use for either. You did not provide the details of the rest of your build, so it's really hard to answer your question!

How thick ceiling would you do?

For what purpose? If this is the inner-leaf ceiling, then it should be the same surface density as the inner-leaf walls. If the "3 layers of gypsum" is your inner-leaf wall, then that's what you need for the ceiling too: 3 layers of gypsum.

I want a lot of low frequency absorbtion and keep as much floor area free as possible.

Low frequency absorption is normally accomplished with large bass traps inside the room, but that is not related to the isolation of the room, and it looks like you are talking about isolation. Low frequency absorption is part of the acoustic treatment that goes inside the finished room: treatment is not isolation, and isolation is not treatment. They are two very different aspects of acoustics. Isolation means "stopping the sound from getting in or out". Treatment means "making the room sound good inside". Two different things. Absorbing low frequencies is treatment, not isolation.

Then again, it´s nice to have a high celing when the room is done.

A high ceiling is very good, if you have the space to do that, and as long as the final room ratio is still good. - Stuart -

Thanks Stuart! Really good points, made me realize i´ve been very unclear about things. The Isolationshell is finished, very silent this room and luckily in a calm area of this industrial plot. The Viscoelastic adhesive is Swedac DG-A 2 I want a ceiling that eats a lot of bass, My plan changes daily as i try to get my head around why basshangers work and why a lot of industrial celings are made with cem-in-woodchip type heavy ceilings with rockwool above. I also want it angled with reflection in the mid/height and right now i think about isolation/basshangers and black acoustic fabric covered with hardwood "stripes". If it can be solved with clever use of cheap material and little labour it´s a big plus:) Thanks again for great input! /Toby