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Treated my room, what else?
Old 13th July 2016
  #1
Gear Maniac
 

Treated my room, what else?

Hi guys
Couple months ago I posted this post:
Treated my bass response now the room is to dead

Since then I added more bass traps and manage to improve my overall room EQ curve. Attached mdat file

I managed to reduce the bump at 120hz mainly with setting my monitors behind my desk instead on my desk. I'm now sitting at the center of of a perfect 1 meter triangle.

What else to improve that 120hz bump and are the RT60 measurement any good?
Attached Files
File Type: mdat Jul 13 13_12_23b.mdat (2.54 MB, 110 views)
Old 14th July 2016
  #2
Gear Maniac
 

It's kind of hard to figure out what is going on when the two speakers are measured together. Need to do left and right one after the other in a single .mdat file.

I am not good enough to figure it out, but I find your spectrogram strange. No resonnances at all, but a big bump at 120 Hz. Are you applying a house curve, using a sub, or ?

There are also strong dips at 280 and 470. I am not sure if they are important. If so, they are quite probably caused by SBIR and can be reduced by applying absorption at the first reflection points.
Old 14th July 2016
  #3
Gear Maniac
 

Hi there, here are the L&R separated. No I don't have a sub or Eq curve applied.
And recent picture.
Attached Thumbnails
Treated my room, what else?-img_1772.jpg  
Attached Files
File Type: mdat 2016jul14.mdat (7.62 MB, 134 views)
Old 14th July 2016
  #4
Gear Maniac
 

Ok,

Do you have a cloud, and a picture of your back wall? What size is your room?

Looking at your mdat file, I don't see much resonnances, so your basstraps are controlling the modes correctly. However, if you look at the initial slice of the waterfall (or decay/spectrogram) you see that the frequency response is not good enough, right from the start.

This could be your monitors, monitor room cal switch, wrong mic calibration, wrong house curve...

This could also be caused by 1st reflections that are not well treated. 1st reflections occur from all the walls, the ceiling and your desk. They are located at poolshots from your speaker to your listening spot and can be localized with a mirror. I suspect your treatment to be too thin, especially at the front. Low frequencies are emitted in all directions by the speaker. If they are not well attenuated, the wave coming from the back and side of your speaker will come back to you and will combine with the direct sound. Low frequency gets a lot of support, but not the high frequencies! You would need a Minimum of 15 cm of Rockwool on the right spots, aim for 30...
Old 14th July 2016
  #5
Gear Maniac
 

Hi
My front wall covered with 20cm rockwool panels, my sides\ER covered with 5 cm. My room is 3.20 x 1.70 (I'm sitting cross the short wall) it build like a container in shape.
I have a cloud, I've attached more pictures.
whats "monitor room cal switch" you mean EQ?
Attached Thumbnails
Treated my room, what else?-img_1828.jpg   Treated my room, what else?-img_1827.jpg  
Old 14th July 2016
  #6
Gear Maniac
 

Are you using dense Rockwool? Like rigid pannels? (Comfort Board IS ) When working with thick treatment, it has to be somewhat loose. I would call those mattresses instead (Safe N Sound). Dense pannels work somewhat, but when you add thickness, you gain next to nothing. Dense pannels don't let the bass go through, they reflect it instead. I was using them unframed and the pannel itself would start to resonate, I could see this in my spectrograms.

So if your front bass traps are made of dense Rockwool, they will work to damp the modes, but they might operate as new extra early reflection points because of their angle. This would explain everything!!
Old 14th July 2016
  #7
Lives for gear
 
akebrake's Avatar
 

Looks like (on a photo post #5 ) you have an USB mic on a small tripod on the desk. Where are the microphone positioned for the actual measurements uploaded in post #3 ? 4 feet above the floor ear hight? No chair close?

Best
Old 14th July 2016
  #8
Gear Maniac
 

Quote:
Originally Posted by Sailboarder View Post
Are you using dense Rockwool? Like rigid pannels? (Comfort Board IS ) When working with thick treatment, it has to be somewhat loose. I would call those mattresses instead (Safe N Sound). Dense pannels work somewhat, but when you add thickness, you gain next to nothing. Dense pannels don't let the bass go through, they reflect it instead. I was using them unframed and the pannel itself would start to resonate, I could see this in my spectrograms.

So if your front bass traps are made of dense Rockwool, they will work to damp the modes, but they might operate as new extra early reflection points because of their angle. This would explain everything!!
Hi
The Rockwool at the front wall is at 80/kg density (20cm) I was told this is ok for that thickness.
akebrake - I messure the room at my listening position.
Old 14th July 2016
  #9
Gear Maniac
 

Quote:
Originally Posted by kfir26 View Post
Hi
The Rockwool at the front wall is at 80/kg density (20cm) I was told this is ok for that thickness.
I don't have time to dig more into this. If I recall well, Comfort board is 60 and I'm sure that over 5 cm I didn't gain much. There are simulators you can try, and it was confirmed by simulation.

Dense pannels will have let's say 20% absorption with 2.5 cm, but it doesn't increase much when you get thicker. They work well to reduce the modes because modes strike the pannels several time. But to reduce SBIR, you need to have a good single pass absorption and dense pannels cannot do it. You need looser stuff and thickness to absorb it well. I think Safe'n sound is 30 kg/m3

My numbers may be wrong but the general concept is.
Old 14th July 2016
  #10
Gear Maniac
 

Quote:
Originally Posted by Sailboarder View Post
I don't have time to dig more into this. If I recall well, Comfort board is 60 and I'm sure that over 5 cm I didn't gain much. There are simulators you can try, and it was confirmed by simulation.

Dense pannels will have let's say 20% absorption with 2.5 cm, but it doesn't increase much when you get thicker. They work well to reduce the modes because modes strike the pannels several time. But to reduce SBIR, you need to have a good single pass absorption and dense pannels cannot do it. You need looser stuff and thickness to absorb it well. I think Safe'n sound is 30 kg/m3

My numbers may be wrong but the general concept is.
I'm not sure that is the problem, but then again what do I know..
Old 15th July 2016
  #11
Gear Maniac
 

Do you have anything better to try?

If I were you, I'd look into this for 3 reasons. 1- Others said earlier you needed to use thicker material to treat lower frequencies. 2-I used dense Rockwool in my living room without great results. Tried doubling it without much improvement. Using SNS made a big difference and it can be explained theoretically. I'm will never buy dense Rockwool again. 3- (That one is more personal) I solve technical problems daily at my job. Sometimes a problem puzzles you. When I get an Eureka moment that fix the puzzle, I'm usually on the right track, but not always...
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