April 4, 2019
Hi, I have made several spectral measurements in my mixing room and I have noticed the same problem. I Have a dip from 600hz to 2khz ranging from -1db to -4db. Should I make my diffusers in that range so I can reinforce those attenuated frequency’s by diffusing them? Let’s say i’m going to make a QRD diffuser that diffuses 700hz and cuts off at 2000hz. does it seem right ?
thank you for your videos !
Diffusion will not assist you with peaks and troughs in frequency response. It will actually make them worse. You must use broadband absorption to treat the issues.
Are you sure about this? It seems to me that nadeau777 was on the right path with his suggestion.
As far as i know, the very main purpose of phase grating is to keep the energy within the room without disturbing the frequency response, by spreading the energy out in time.
S, Diffusers can not add anything to the room response other than higher Rt-60 times.
I will have to respectfully disagree with you there Dennis. Specular reflection from one plane will cause peaks and dips in the frequency response, because all the energy will arrive with a specific time delay in respect to the source. Depending on this time delay, some frequencies will cause destructive and some will cause constructive interference, causing peaks and dips.
A properly designed and built QRD will spread that same energy out in time, this will create a more even interference-pattern. There will no longer be certain frequencies where all the reflected energy has a perfect 180deg phase shift caused by a single time delay.