Diffusers question for pros

Hi I am about to build the diffusers for my 2 rooms (live room and drums booth). Live room is 4,5 m x 7,5 m with 2,5 m height and the booth is 2,5m x 2,5m x 2,5 m . I have on the ceilings in both rooms 7 cm rock wool ( isover ) covered with wood frames with fabric over the frames . I also have the bass traps in every corner in different dimensions and i am about to build some more bass traps. My plan is to build diffusers 60 cm x 60 cm using this formula ( see the pic.) and try to deal with freq from 500 Hz til 4Khz . My questions are : -usually this kind of diffusers are build of wood but i was thinking of building them with styropor , what do you think about it, is it a good idea or should i stay with wood ? - How many diffusors do i need for this rooms and where should i place them ? Thanks

Hi everyone, my first post here. As long as you use high-density styropor and perhaps coat it with something to give it a more reflective surface it might work although I would recommend you to use wood if its not to inconvenient for you. When it comes to placement the general rule of thumb is to diffuse if the time difference between source-listener and source-reflection-listener, is longer than the “Haas-zone”, witch is between 10-20 milliseconds depending on program material. If the distance were shorter than roughly 3 meters then you would normally absorb instead.

I would also, if I were you, consider the one-plane-QRD; http://www.mhsoft.nl/diffusor.asp#calcul …witch is a lot easier to build and quite effective but only in on plane of course.