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-   -   acoustic treatment for a small live room (https://www.gearslutz.com/board/studio-building-acoustics/1252891-acoustic-treatment-small-live-room.html)

ReDRuMx 17th March 2019 01:46 PM

Very interesting thread.

Could someone post their own ACTUAL measurements of rooms treated with HH devices?

Please :)

golgoth21 17th March 2019 09:02 PM

Quote:

Originally Posted by Jens Eklund (Post 13852998)
https://www.gearslutz.com/board/atta...erent-gaps.jpg

300 mm deep HH array incident angle from Soundflow.

One panel has 6 mm gaps and the other one 7 mm gaps between the slats. So even if you mess up by this much; the performance is almost identical. There is no precision required to build a HH array.

How big in order it has an impact on my room ? 150cm X 60 on the rear wall ?

Thanks in advance.

G21

golgoth21 19th March 2019 09:22 PM

Quote:

Originally Posted by JayPee (Post 13864606)
No. Alpharock is way too dense for SSC.

Reading is the key. I found out the correct GFR for SCC. Below 15 is the key. Below 10 better.

Still computing informations...

golgoth21 22nd March 2019 04:39 PM

2 Attachment(s)
Hello

I retrieved some stuff.

Now there are only 4 SCC made of ISOVER 26kg/m3 - GFR 15

Sorry i did the measurement with the 2 HP all together.

Next : First reflections.

golgoth21 25th March 2019 02:15 PM

1 Attachment(s)
Hello

I followed the advice given by Jens. I built a sealed trap with slats, 6/7 mm slits, 90 cm slats. 30 CM Rockwool Rockmur. Back is closed.

Size is 139X64X30

I placed it on the front wall. It lays on the ground, That's the only room i have for this trap.

https://www.gearslutz.com/board/atta...1&d=1553520349

Just above this trap, i have room for 20 cm. I'm going to stack 2 traps of 20CM deep, made of 2 sheets of Rockwool RockPlus (50Kg - GFR about 15)

Am i on the good track ?

Jens Eklund 26th March 2019 09:16 AM

Quote:

Originally Posted by golgoth21 (Post 13885581)
I followed the advice given by Jens.

?

I have not provided you with any recommendations. The example posted earlier was only to demonstrate a point in a side discussion.

Also; you don’t add treatment where “there´s space”: you add treatment on relevant surfaces (and hopefully there´s space to do so on these surfaces). If your modal issue is related to a pair (or all 4) walls; treating the floor will have little or no impact:

https://www.gearslutz.com/board/stud...ml#post8672631

And finally; even if related to the floor (and ceiling): treating a very limited area when the issue is related to possibly the entire ceiling/floor area, will most likely do close to nothing.

Jens Eklund 26th March 2019 09:29 AM

… But looking at your waterfall plots and realizing that the time scale is different on the before and after graphs; you actually improved the situation surprisingly considering the very small area treated and not even on a related surface area (for about 50 Hz) if panel is lying on the floor …

I´d say your room is good enough to benefit from 2 subs and a DSP to be able to correct the low end (and to be able to x-over above possible floor related SBIR dip in the 110-170 Hz or so range) with decent results.

golgoth21 27th March 2019 04:30 PM

6 Attachment(s)
Quote:

Originally Posted by Jens Eklund (Post 13887370)
… But looking at your waterfall plots and realizing that the time scale is different on the before and after graphs; you actually improved the situation surprisingly considering the very small area treated and not even on a related surface area (for about 50 Hz) if panel is lying on the floor …

I´d say your room is good enough to benefit from 2 subs and a DSP to be able to correct the low end (and to be able to x-over above possible floor related SBIR dip in the 110-170 Hz or so range) with decent results.

Hello, thank you.

The pannel is laying horizontally on the floor. Its face is looking at the opposite wall, not at the ceiling.

I ve added 20 CM of rockwool 50kg, GFR around 15, on the wall, above the pannel mentionned earlier, up to the ceiling.

And i ve added 10 CM of rockwool 50 Kg / GFR on the first reflections spots (side walls and ceiling).

Here is what i have now : It's much better. Except this huge dip at 1KHz. I'm looking for what to do. Moving the cloud, moving the speakers, retrieving the thick carpets.

Next step : i will add a non-woven polypropylene fabric on some of the pannels (not the first reflections); in order to rise the decay up.

https://www.gearslutz.com/board/atta...1&d=1553700345

https://www.gearslutz.com/board/atta...1&d=1553700447

https://www.gearslutz.com/board/atta...1&d=1553700411


https://www.gearslutz.com/board/atta...1&d=1553700396

Buggaluggs 31st March 2019 12:04 AM

Don't want to de-rail the thread, but, what (how) are you using to get the spectrum analysis? I have a clean slate room I am about to start on and this looks like a great tool to get me going in the right direction.

Soundman2020 31st March 2019 02:26 AM

Quote:

Originally Posted by Buggaluggs (Post 13896439)
Don't want to de-rail the thread, but, what (how) are you using to get the spectrum analysis? I have a clean slate room I am about to start on and this looks like a great tool to get me going in the right direction.

REW:

John Sayers' Recording Studio Design Forum •

View topic - How to use REW to analyze the acoustics of your room...
.

golgoth21 2nd April 2019 11:40 AM

6 Attachment(s)
Okay, i learned so much these past weeks (months).

Here are my last REW.

I have in my room : 4 Corners traps (SCC) made of Isover 26kg/m3 GFR around 15. The front corners are covered with a 100 g/m2 non-woven polypropylene fabric

I've built a front wall made of a 30 cm deep slated box (60CM high X 135 Large),
rockwool around 26 kg/m3 GFR close to 9.

Above there is a 20 CM deep absorber, Rockwool 50Kg/m3 GFR around 13/14. 120 CM High X 135 Large), the fabric is a 70 g/m2 non-woven polypropylene.

I'm still building the first reflections traps. They will be 20 cm deep. 50 kg/m3 GFR around 13/14. One on each side (mirror trick)

The last REW is better (i guess, and so to my ears). Even if the waterfall shows highs looking like a comb shell.

Before
https://www.gearslutz.com/board/atta...1&d=1554203518

So far
https://www.gearslutz.com/board/atta...1&d=1554203881
My room is closed to the street. REW looks better late in the evening (night)


Before
https://www.gearslutz.com/board/atta...1&d=1554203517


So far
https://www.gearslutz.com/board/atta...1&d=1554203519


Before/After
https://www.gearslutz.com/board/atta...1&d=1554203518


I hope First reflections traps will improve something. In fact, i'm thinking about the axial width mode at 120Hz.

The door is located almost in the middle of the lenght of the longest wall. I'm thinking about hooking a trap on the door, in order to kill this 120Hz mode.

I'm thinking about a trap on the backwall, for the first reflections. I don't know if it needs to be 20 CM deeps. It will be hooked above the piano. I don't know if it is smart to do so.


Pictures next.

golgoth21 2nd April 2019 03:04 PM

Me again.

On various threads about first reflections i read the depth should be up to 6inch.

What about 8 inch ?

4 inch, so far, did not show much improvement.

Bye.

[EDIT] I found out : https://www.gearslutz.com/board/bass...h#post11713477 [EDIT]