Room Frequency Response Advice

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Room Frequency Response Advice

Postby mostermeier » Sat May 22, 2010 8:15 pm

I am seeking advice on improving my basement studio. I have attached a scale layout with pictures. I have performed an analysis using FuzzMeasure of the acoustics in my studio and have attached below the frequency response as well as waterfall and RT30 data. For the frequency response, the big dip at 9k is a result of the fact that the mic doesn’t pick this frequency up well.

I had the closet put in for storage and to make the room less square, but I think the one sheet of drywall is not really making the room “less square” for the low end. The right wall that separates the studio from the closet is only one layer of drywall thick (the closet has no drywall on the inside; you can see this in the pictures). I was thinking that filling in between the 2x4s with Owens Corning 705 might be a good idea because a lot of low-end sound is traveling back and forth across this wall reflecting off the cements walls in the closet. Is this a good idea?

I have played a lot with acoustic panel placement (the acoustic panels are from ATS and 4” thick, except for the two on the ceiling that are 2” thick), listening position, and speaker placement, and this is the best set up I have tried. But if there are any other suggestions for improving things (i.e. how to address the dip between 400 and 500 Hz and <150 Hz), I’d be grateful to hear them. Also, I’d be interested in any comments on how well I have done for a small size room.

Thanks,
Marc
Studio Layout.jpg
Studio Layout
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Speaker analysis.jpg
Frequency Response
(541.72 KiB) Not downloaded yet

Waterfall_plots.jpg
Waterfall and RT30
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Re: Room Frequency Response Advice

Postby Scott R. Foster » Sun May 23, 2010 5:32 am

what happens to that 135 Hz dip when you slide the mic back a couple of feet?
SRF
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Re: Room Frequency Response Advice

Postby mostermeier » Sun May 23, 2010 11:55 pm

I tested the left speaker two feet back from the sitting position (which puts the mic about in the center of the room). Things change quite a bit. See attached.
TwoFeetBack.jpg
Comparing Listening and 2' Back (Left Speaker)
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Re: Room Frequency Response Advice

Postby Scott R. Foster » Mon May 24, 2010 1:19 am

starting to look like a front to back modal problem... try the same comparison with the right side.

easiest solution might be a sub you can move around to an optimal location and a dead front wall?
SRF
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Re: Room Frequency Response Advice

Postby mostermeier » Mon May 24, 2010 11:40 pm

Here are the results from the right speaker.

I was considering a sub to help with <150Hz. But I've read many places that they can cause more problems than they fix, which is why I have been hesitant.

Do you suggest making the front wall dead by adding more of the panels I already use or something more drastic?

twofeetbackright.jpg
Comparison of Listening and 2' back (Right Speaker)
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Re: Room Frequency Response Advice

Postby Scott R. Foster » Tue May 25, 2010 12:10 pm

Adding a sub does add another degree of freedom - so I'll concede it can make getting things arranged more complicated, but it strikes me that this is more because there is a larger set of possible solutions, not because the sub "causes more problems than it fixes". I have seen many circumstances where using a sub allowed a quick fix to getting the LF room responses at the LP out of a big null like the one you have at 135 Hz.

Looks to me though that if you add a few more panels to the front wall [try adding a couple of ceiling/wall and floor/wall corner panels perhaps] and with a bit of judicious scooting around of the furniture you might get out of that big hole you are in without a sub.
SRF
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Re: Room Frequency Response Advice

Postby mostermeier » Wed May 26, 2010 12:00 am

Thanks. I will give these ideas a try.

-Marc
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