Hi Steve,
Thats almost same dimensions as my room..
8.6x5.6x3.2m .. I focussed on keeping noise out and in with solid concrete filled blockwork , doubly glazing and dense ceiling. No internal linings as these could be be unpredicatable membrane absorbers .. I get about 25db ambient except when a harely goes past or rain belts down.
Acoustic treatments are applied in median plane ( 600 to 1800mm high ) .. baffles on ceiling and corner bass traps
It is a fantastic room .. a listening lab my acoustic engineer buddy calls it !
If doing again I would pay more attention to the builders work in acoustic sealing of joints between materials ( walls and ceilings) and I would perhaps hang ceiling (
https://durrapanel.com/?gclid=CjwKC...1ENAePmiIpHC2GYPbZZvOKJ860rIvEIhoCzhkQAvD_BwE)
Off resilient hangers to minimize structure born sound from the roof
The raytrace on thr armoc site mentioned by sbnx is also a great tool
I have speakers on long wall .. I believe you get a better result with first reflections thus a ckearer phantom image with that setup
Cheers
Phil
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