Room measurement! what now?

[Tesla Coil]

Hello,

I have been adding bass trap after bass trap and still have a huge bump at 40 Hz...... 18 traps into this whole thing (mostly GIK.... and a few 705 home made traps) and I am wondering if there is anything else i can do???


is it that 40 hertz is 28 ft long and nothing is going to stop it???


By the way all corners are trapped... front and back walls too.


cheers

[DanDan]

The lowest axial mode is often impossible. You will just have to live with it and work around it. Get to know where it lives. Avoid listening in its peak areas. Note that such a mode creates an entire wall of high pressure, not just in the corners.
DD

[apeak]

I wonder if this will work for you - 'Bag End E-Trap Electronic Bass Trap'? They claim that it can target up to two problem frequecies. It lists at around $1200. Might take a little experimenting with the tuning and placement though.

[Tesla Coil]

Thats what i thought.... thanks for the Bag end suggestion.

I guess i did not expect to get much better, as the room was not designed to be a studio.


Thanks again guys!

[mikahanau]

Hi
When your reverbation time is even (no ringing at 40hz), and you have just the peak at 40 hz, you can usw PEQ to reduce this peak.
I did the same in my Studio, and it sounded great.
The frequency response of your room looks great. good work.

cheers
Mika

[Pier]

Originally Posted by Tesla Coil

Hello,

I have been adding bass trap after bass trap and still have a huge bump at 40 Hz...... 18 traps into this whole thing (mostly GIK.... and a few 705 home made traps) and I am wondering if there is anything else i can do???


is it that 40 hertz is 28 ft long and nothing is going to stop it???


By the way all corners are trapped... front and back walls too.


cheers

What software did you use on the mac to measure your room?

[ciro]

Originally Posted by mikahanau

Hi
When your reverbation time is even (no ringing at 40hz), and you have just the peak at 40 db, you can usw PEQ to reduce this peak.
I did the same in my Studio, and it sounded great.
The frequency response of your room looks great

Ciro

[Glenn Kuras]

Originally Posted by mikahanau

Hi
When your reverbation time is even (no ringing at 40hz), and you have just the peak at 40 hz, you can usw PEQ to reduce this peak.
I did the same in my Studio, and it sounded great.
The frequency response of your room looks great. good work.

cheers
Mika

I think you could do that if all things are equal. I would though recommend shooting the room with the following program to see what is going on with the decay times (ringing).
Room EQ Wizard - REW Home Page

Tesla Coil,
It is hard to say if there is other things that can be done without more info on your room. Since you bought from us I would HIGHLY recommend emailing me and let us dig into your set up to see what can be done. It might be as easy as moving your mix spot a bit, moving around the panels to better deal with certain modes or adding a bit more absorption (lets use that as the last thing ).

BTW thanks for your purchase.

[pianogineer]

Originally Posted by Tesla Coil

Hello,

I have been adding bass trap after bass trap and still have a huge bump at 40 Hz...... 18 traps into this whole thing (mostly GIK.... and a few 705 home made traps) and I am wondering if there is anything else i can do???


is it that 40 hertz is 28 ft long and nothing is going to stop it???


By the way all corners are trapped... front and back walls too.


cheers

Hey Tesla -- what mic did you use to make your measurement? I'm thinking of doing one but trying to figure out if it's necessary to buy one of the reference mics that REW suggests, or if I can do it with a 'standard' mic (only thing I really have handy is a SM58).

[ciro]

You have 18 traps in the room - if you fill the space behind of some corner traps (supposing you have 4" rockwool, let´s say) with "fluffy" fiberglass/rockwool, it should improve the absorption in the sub lows.

Ciro

[Tesla Coil]

Wow, this is the most response i have ever received on a gearsluts thread!

the acoustics forum is were all of the nice gearslutters hang out!

First, Glenn, you rock. Ill contact you eventually to see if there is anything else we can do.

Second, (Pier) i used Room eq wizard to measure the room.

While i did not post the picture of the decay times i will say that 40Hz is only 10dB down after 160ms... where as everything from 200Hz up is about 40dB down.


Third, (pianogineer) the microphone i used was made by Genelec and has an associated text file that can be imported to room eq wizard to insure a completely flat measurement. it is critical that you know that both your microphone and sound card are completely flat... an sm58 is not even remotely flat.

Thanks again!

[Glenn Kuras]

First, Glenn, you rock. Ill contact you eventually to see if there is anything else we can do.

Good deal. If and when you do contact us please refer to this thread.