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Really trying to upgrade my room
Old 8th May 2019
  #1
Gear Head
Really trying to upgrade my room

Hey guys,

So following on from my last post, this weekend just gone I grabbed a measurement mic and did lots and lots of testing with Fuzzmeasure. I've detailed my process and would be grateful for any advice on improving things further.

Attached is a picture of how my room was laid out - but it has the dimensions. The window is the entire length of the wall. It's also carpeted.

Step 1: Place a speaker firing into the wall/floor corner of one of the corners in my room. Place mic at assumed best listening position (38% 'rule') and play sweeps through the speaker, looking at low frequency response. Move the mic about 5cm at a time and find the spot with the flattest response.

Step 2: Set up the speakers in an equilateral triangle with the listening position. Play sweeps and measure response. (See image "Off The Front Wall" - Purple)

Move the speakers along the equilateral triangle lines forwards and backwards until I find the position with the best response. - Here's the interesting part (which I've been reading about a lot on this forum)... The speakers right up against the window provides the flattest response. (see image "Against Window" - orange). So many problems have been solved! There's some comb filtering going on but this is in a room with no treatment.

Step 3: Start introducing treatment into the room. (Which I'll do in a new post for neatness).
Attached Thumbnails
Really trying to upgrade my room-off-wall-freq.jpg   Really trying to upgrade my room-off-wall-waterfall.jpg   Really trying to upgrade my room-against-window-freq.jpg   Really trying to upgrade my room-against-window-waterfall.jpg   Really trying to upgrade my room-my-old-room.jpg  

Old 8th May 2019
  #2
Gear Head
I moved the following treatments into my room:

4X Gik soffits
12x DIY 100MM traps made with Rockwool RW3 (60KG/m3)
2x rolls of Knauf 'fluffy' insulation 100mm thick (still in wrapping)
2x rolls of Knauf 'fluffy' insulation 170mm thick (still in wrapping)

I placed panels at the first reflection points, straddled the back corners with DIY panels and placed the soffits on the back wall. The rolls of insulation were placed in the alcove to the right, apart from 1 roll of the 170mm knauff which was placed between the speakers on the floor against the front wall.

This was the result
Attached Thumbnails
Really trying to upgrade my room-170mm-freq.jpg   Really trying to upgrade my room-170mm-rt.jpg   Really trying to upgrade my room-170mm-waterfall.jpg  
Old 8th May 2019
  #3
Gear Maniac
 

seems almost identical
Old 8th May 2019
  #4
Gear Head
I then removed the 170mm knauf along the wall and placed one 100mm roll in each corner by the speakers. They didn't fit straight against the corner as the speakers were too close, but I pushed them back as far as I could.

This was the result.
Attached Thumbnails
Really trying to upgrade my room-100-corner-freq.jpg   Really trying to upgrade my room-100mm-corner-rt.jpg   Really trying to upgrade my room-100mm-corner-water.jpg  
Old 8th May 2019
  #5
Gear Head
Quote:
Originally Posted by KSMUSIC View Post
seems almost identical
The dip at 150 was reduced a lot I thought.
Old 8th May 2019
  #6
Gear Head
This is the 100mm rolls in the corners and the 170 roll underneath.
Attached Thumbnails
Really trying to upgrade my room-170-100-freq.jpg   Really trying to upgrade my room-170-100-rt.jpg   Really trying to upgrade my room-170-100-water.jpg  
Old 9th May 2019
  #7
Lives for gear
 

There's a huge, massive peak around 37 Hz... have you figured out what that is, and what you can do about it? My guess would be either an axial mode or some type of structural resonance.

Plus, you really should do the tests with just one speaker at a time, so you don't get the false mess in the high end.

I wish I could help you more by analyzing the actual data, but I'm a REW guy, not a Fuzzmeasure guy, so it wouldn't help if you posted it. I guess that Fuzzmeasure can export an actual Impulse Response in .wav format, that could be imported into REW? That would be one way of doing it. But it should be a set of three tests: just the left speaker, just the right speaker, then both together. Between them they tell the full picture. I'd need all the data: from all of the tests that you have done so far, to compare.

- Stuart -
Old 9th May 2019
  #8
Gear Head
Thanks for your feedback, I think it's probably a structural resonance because it's been there throughout the process (ever since I put the new monitors in my room).

I was wondering (because it's so low) wether I could treat this one with EQ?

Yes I can export impulse responses, I'll do that now
Old 9th May 2019
  #9
Gear Head
This was the final rough placement of the acoustic treatment. The main purpose of this thread is really to decide the best way to treat this room, and my main problems were in the low end - with the large nulls at 65 / 83 ish and the big peak around 120.

There was some modal ringing around 100hz (which I don't think I have a waterfall plot of) but this was solved with a DIY panel spaced 100mm off the wall about 2/3's back into the room on the left hand wall.
Attached Thumbnails
Really trying to upgrade my room-final-rough-placment-freq.jpg   Really trying to upgrade my room-final-rough-placment-rt.jpg   Really trying to upgrade my room-final-rough-placment-water.jpg  
Old 9th May 2019
  #10
Gear Head
What was interesting is that once I moved two 4x12 guitar cabs into the room (placed along the right hand side 5x8 wall, the RT20 of 31.5hz went from 0 to 0.457!
Attached Thumbnails
Really trying to upgrade my room-cabs-freq.jpg   Really trying to upgrade my room-cabs-rt.jpg   Really trying to upgrade my room-cabs-water.jpg  
Old 9th May 2019
  #11
Gear Head
Here are the IR files for the last two plots
Attached Files

With cabs IR.wav (3.00 MB, 347 views)

Rough placement IR.wav (3.00 MB, 351 views)

Old 9th May 2019
  #12
Lives for gear
RT 20 (RT x) is irrelevant in small (acoustic) spaces.

Your 35-ish Hz room is your 1-0-0 room mode. It's your biggest problem right now.

Comb filtering might come from your big desk.

Most of us use REW here. More details. I encourage you to dl the last version
Old 9th May 2019
  #13
Gear Head
Quote:
Originally Posted by JayPee View Post
RT 20 (RT x) is irrelevant in small (acoustic) spaces.
That's great news, I'll stop worrying about that then!

Quote:
Originally Posted by JayPee View Post
Your 35-ish Hz room is your 1-0-0 room mode. It's your biggest problem right now.
OK. Interesting. Looking back at some of the listening position charts, there were a few that helped with this but also led to large nulls at 60is + 80ish hz. I'm open to moving everything round again if this would be beneficial, and DIYing more treatment / adjsuting existing DIY's is high on the list (perhaps experimenting with an infinite baffle?) if this would help

Quote:
Originally Posted by JayPee View Post
Comb filtering might come from your big desk.
It's not actually in the room at the moment - only speakers and treatment. But I'm more than happy to build a smaller one - incorporating the rack gear to the right hand side underneath it.

Quote:
Originally Posted by JayPee View Post
Most of us use REW here. More details. I encourage you to dl the last version
ok cool. I'll look at importing the IR's into REQ and uploading the REQ files here
Old 9th May 2019
  #14
Gear Head
Here's (I think!) the REW file.
Attached Files
File Type: mdat With cabs REW.mdat (10.95 MB, 14 views)
Old 9th May 2019
  #15
Lives for gear
 

Quote:
Originally Posted by Twiggy View Post
Here's (I think!) the REW file.
Yup! It worked fine. And below is the real Waterfall for your low end. Big problem at 34 Hz. Smaller ones at about 71 Hz, and 119 Hz, and a few others.

I would suggest that you need some deep bass trapping. You might want to consider using some type of tuned trap for that 34 Hz thing: Maybe perf panel, or membrane if you want to try making them yourself. GIK has tunable traps that go down that low, I think. Here's a link to a thread about membrane traps, and how to tune them and make them: Tim's Limp Mass Bass Absorbers .

Now that you know you can export IR files, maybe you can export some of the other ones. And now that you ALSO have REW on your system, just use that from now on. If you want a quick tutorial on how t set it up and use it, trey here: http://www.johnlsayers.com/phpBB2/vi...hp?f=3&t=21122 .

Please make sure to do the speaker individually, as well as together. As I mentioned before, you need both types of tests, as each one ells you about different parts of the spectrum.

- Stuart -
Attached Thumbnails
Really trying to upgrade my room-twiggy-rew-wf-12-500.png  
Old 12th May 2019
  #16
Gear Head
Thanks for the reply Stuart!

Quote:
Yup! It worked fine. And below is the real Waterfall for your low end. Big problem at 34 Hz. Smaller ones at about 71 Hz, and 119 Hz, and a few others.
Yes, the 119Hz peak was the original reason I started on this endeavour It was a little lower in my old set up (105Hz - ish) along with nulls as outlined before. Just looking back through some of the other listening positions, they don’t have the 34hz bump, but they do have significant nulls below 100hz. Am I correct in thinking that it might be easier to treat this bump than it would be to treat those nulls?

Quote:
I would suggest that you need some deep bass trapping. You might want to consider using some type of tuned trap for that 34 Hz thing: Maybe perf panel, or membrane if you want to try making them yourself. GIK has tunable traps that go down that low, I think. Here's a link to a thread about membrane traps, and how to tune them and make them: Tim's Limp Mass Bass Absorbers .
I agree. I'd already planned to get some deep bass trapping done, but then I started reading about SBIR which has (I think) helped a lot in the low end (removing the nulls) so now it's try to even out the peaks. My thoughts at present are to use the following equipment to do:

4X Gik soffits
12x DIY 100MM traps - Rockwool RW3 (60KG/m3) [28000 pa.s/M2]
2x rolls of Knauf 'fluffy' insulation 100mm (still in wrapping) [5000 pa.s/m2]
2x rolls of Knauf 'fluffy' insulation 170mm (still in wrapping) [5000 pa.s/m2]
3x DIY 2D Quadratic Residue diffusor [made from wood] - Not sure where to place these....

Place all 4 GIK soffits in the rear corners. (which will leave a little space at the top - which I could place some DIY corner traps on top of to get them floor to ceiling).

Place some deep trapping at the first reflection points on the rear wall. 170mm knauf insulation (which has a Flow resistivity of 5000 Pa.s/m2), with a 100mm air gap.

Treat the other first reflection points on the side walls. This can be done either with the existing DIY panels (100 rockwool 60KG m/3 [Flow resistivity of 28000 Pa.s/m2] with a 100mm air gap), or by building some new panels out of the knauf insulation (either 100mm or 170mm) - not sure which is preferable here?

Treat the corners under the speakers by building a multi layer trap with knauf insulation and a perforated panel tuned to the 120hz range (which I measured as having a lot of energy in those corners). The GIK soffits and existing panels are too tall/wide to fit here.

Use two DIY rockwool panels as a cloud spaced 100mm off the ceiling. (Or would using the 100/170 knauff be better here?)

I am also toying with the idea of making an infinite baffle for them. I could construct the frame and fill it with the rigid rock wool I already have (plus get more), but I need to do some more reading on infinite baffles first before move forward with this.


Quote:
Now that you know you can export IR files, maybe you can export some of the other ones. And now that you ALSO have REW on your system, just use that from now on. If you want a quick tutorial on how t set it up and use it, trey here: http://www.johnlsayers.com/phpBB2/vi...hp?f=3&t=21122 .
I’m on a Mac and REW is pretty sluggish and seems a little clunky. I’m happy to measure in Fuzzmeasure then export the IR into REW and export an MDAT if that’s not going to cause any issues?
I’ll have a look at the John sayers link you posted though thanks for that

Quote:
Please make sure to do the speaker individually, as well as together. As I mentioned before, you need both types of tests, as each one ells you about different parts of the spectrum.
Thanks, somehow I missed the part about measuring each speaker individually, as well as together. I think because I was so focused on fixing the problems in the low end I didn’t do any reading into looking at the high end because I had my first reflection points treated with DIY panels and didn’t feel I was having any problems with them. But I’ll definitely do like you said when I’m testing again.
Old 23rd July 2019
  #17
Gear Head
Hey guys,

Thanks again for the help last time. I had a demo pair of speakers so had to send them back and wait for mine to arrive, which they have!

I've remeasured (with both speakers [Yellow], just left [Red], and just right [Purple]) and have included a dropbox link to the REW file here, as well as the frequency response graphs.

https://www.dropbox.com/s/igf6h1yudw...2019.mdat?dl=0

Naturally that 34hz problem persists (as it's a 1-0-0) room mode as JayPee pointed out previously, though now I seem to have a huge null around 320Hz.

I've also included pictures of where I have the treatment in the room at present (any of this can be changed - it's only temporary positions at the moment.

As a recap: all black panels are Rockwool RW/3 60KG/m3 (I have two more of these that I will probably use as a cloud - unless the heavy carpet negates the need for this?).
The rear corners have GIK soffits.

Thanks again for all the help so far!
Attached Thumbnails
Really trying to upgrade my room-both-speakers.jpg   Really trying to upgrade my room-left-speaker.jpg   Really trying to upgrade my room-right-speaker.jpg   Really trying to upgrade my room-1.jpg   Really trying to upgrade my room-2.jpg  

Really trying to upgrade my room-3.jpg   Really trying to upgrade my room-4.jpg   Really trying to upgrade my room-5.jpg   Really trying to upgrade my room-6.jpg   Really trying to upgrade my room-7.jpg  

Really trying to upgrade my room-8.jpg  
Old 23rd July 2019
  #18
I think you'll need a bit more bass trapping before things start to move significantly.
Old 23rd July 2019
  #19
Gear Head
Ok. Would it be a good idea to turn the rolls of fluffy insulation under the monitors into tri-traps? That would give me bass trapping in the 4 main corners.
Old 23rd July 2019
  #20
Quote:
Originally Posted by Twiggy View Post
Ok. Would it be a good idea to turn the rolls of fluffy insulation under the monitors into tri-traps? That would give me bass trapping in the 4 main corners.
Don't spread the same stuff around. Get more stuff. More.
Old 24th July 2019
  #21
Lives for gear
 

As Johan is politely saying: You need MASSES more treatment in your room. There's no bass trapping in there right now: just some panels on the walls. To get your low end under control, you need large, deep, tall, wide, thick insulation at the key locations in the room. What you have is way short of what you need, no matter where you put it.

- Stuart -
Old 27th July 2019
  #22
Gear Head
I hear you guys. So, I already have 4 GIK soffit bass traps in the rear corners of the room.

The plan is now to DIY some more soffits to add more bass trapping.
From a lot of reading over the past few months, I hope I'm right thinking that the low GSR insulation is best for soffit building. So I'm going to build some 42x42cm soffits (filled with 38 x 38cm squares of Knauff roll - 5000 pa.s/m2).

Two will go in the corners underneath the speakers.
I'll go floor to ceiling in the two 2nd front corners (directly to the left and right of the mix position).
I'll go across the back wall/ceiling corner, and across the left hand wall ceiling corner. (this is purely based on practicality as I wont need to drill into the ceiling to mount these).

I plan to do that this weekend - unless I'm way of in my thinking. I've been planning to do it for a while but these new speakers (and you guys) have kicked my ass into gear

EDIT: There is better treatment planned for the rear wall as well (it's just the 4" panels with a 4" air gap at the moment) but I want to use a combination of broadband and targeted bass absorption (probably perf panel) so will need some time to calculate exactly what that will be.
Old 28th July 2019
  #23
Gear Head
Thanks again for all the help so far guys, it's much appreciated! I spent the weekend making the soffits I discussed in my last post. So I now have soffit traps floor to ceiling in the rear corners, and along the rear wall/ceiling corner. I have soffits almost up to the ceiling of the corners to the left and right of the mix position (the gap is because I'm also building traps to fill the wall/ceiling corner on the left hand side of the room). And I have soffits in the front two corners up to about waist height (the speaker position stops me going any higher). I'll detail the building of these with pictures + descriptions if you guys think they've made a positive impact to my room!

I installed the small traps underneath the speakers, and traps almost floor to ceiling in the left/right mix position corners.

I then moved some traps around and took a few measurements:

1) GIK soffits at rear, DIY soffits in the left/right corners.
2) DIY in rear corners, GIK in the left/right corners
3) DIY in rear corners, GIK in the left/right corners, rear wall/ceiling soffits loosely positioned.
4) Added a roll of 170mm 5000 wool still in the wrapper along the front floor/wall corner
5) Added two 100mm rockwool RW3 (28000 pa.s/M2) panels on the walls directly to the sides of the speakers.
6) Removed the previous panels, and moved one to the middle of the room and one above an existing panel in the intended RFZ (this was purely as it was easy to place them here - I expect them to move)

REW file here: https://www.dropbox.com/s/q9h7jzxjjd...0REW.mdat?dl=0

Because I'm expecting the soffits to do most of the work in the low end, the measurements I've posted here are with both speakers running. I did take measurements of just L and just R speakers running, which I will happily post them for the others if people are interested / think it would be useful.

The most interesting thing is there seems to be a lot of movement in the 100-200hz range, and just above 300 on the frequency response (not always for the best) but I think the waterfall always shows improvements.

Edited to include link to REW file
Attached Thumbnails
Really trying to upgrade my room-diy-soffits-front-gik-rear.jpg   Really trying to upgrade my room-gik-front-diy-rear.jpg   Really trying to upgrade my room-all-soffits-.jpg   Really trying to upgrade my room-all-soffits-.jpg   Really trying to upgrade my room-panels-side-speaker.jpg  

Really trying to upgrade my room-current-setup.jpg  

Last edited by Twiggy; 29th July 2019 at 01:01 AM..
Old 29th July 2019
  #24
4 looks the best to me but the frequency response isn't really the best way to see this. Please post your .mdat, thanks.

And the one thing I think we have not talked about? What's up at 10 kHz with your speakers? Is this a three-way and you have the monitors way above or below the microphone's axis?
Old 29th July 2019
  #25
Gear Head
Quote:
Originally Posted by johannburkard View Post
4 looks the best to me but the frequency response isn't really the best way to see this. Please post your .mdat, thanks.

And the one thing I think we have not talked about? What's up at 10 kHz with your speakers? Is this a three-way and you have the monitors way above or below the microphone's axis?
Whoops, my bad! Edited the previous post with a link to the REW files and here is it for ease:

https://www.dropbox.com/s/q9h7jzxjjd...0REW.mdat?dl=0

I think the mess at 10K is because these plots are all with both speakers running, as I'm mainly interested in the low end with the soffit install. Once that's dealt with I'll turn my attention to those frequencies.
Old 29th July 2019
  #26
I would probably go with 4 but they're quite similar. You can see that your treatment has little effect at 35 Hz where your 1-0-0 mode is.
Old 29th July 2019
  #27
Gear Head
Quote:
Originally Posted by johannburkard View Post
I would probably go with 4 but they're quite similar. You can see that your treatment has little effect at 35 Hz where your 1-0-0 mode is.
Yeah I did notice that. So I'm thinking that in order to treat that I'm going to need a perf panel absorber placed at the appropriate point in the room?
Old 29th July 2019
  #28
Lives for gear
1-0-0 Room mode...
Old 29th July 2019
  #29
Gear Head
Quote:
Originally Posted by JayPee View Post
1-0-0 Room mode...
Ok so I can't fix this with treatment? So is the best way to address this issue to move the monitors forward, off the wall? Before the soffits this lead to pretty huge nulls sub 100hz and a massive peak at about 113hz. Would these be easier to treat than building a lip mass absorber to place on the back wall to try and treat the 32hz mode?
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