LOW FREQUENCY DIP?

[THE KIDD]

Hi,

I've found a low frequency dip in my control room at 80 and 100 Hz. 6 db down at 80 and 9 db down at 100. There is also a rise of 3 db or so at 200. The room has a low and high celing, the low celing is above the monitors and the high celing is above the mix position. The dimensions are as follows:

low celing 89"
high celing 118.5"
front to rear wall 189"
room width 233"

The side walls taper in twords the front wall which has a width of 193".

The rear wall is covered with rockwool hidden behind fabric drapes, the side walls are the same except for 50% which is covered with light T&G timber sheeting, the front wall is also T&G sheeting.

Basically it is a room within a concrete room.

Any ideas on how to improve these dips would be appriciated.

I dont even know where to start looking for the source of these problems.

Thanks in advance.

[Sen]

just my beginner's 0.02...
Sounds like you might need a couple of bass traps in the back corners of the CR (you haven't got any, right?)
How far is the inner wall from the concrete wall? If you have some space in the front corners of CR maybe you could put a few hangers in there...
just plain suggestions....others will come in with more I'm sure
hope something helps

[Ethan Winer]

Kidd,

A hole at 80-100 Hz is very common and as Sen said, you need bass traps to solve this. See John's treatment advice here and on the SAE site, and also see my Acoustics article:

www.recording.org/users/acoustics

--Ethan