Need help in adjusting acoustics in my home-studio - Home Theater Forum and Systems - HomeTheaterShack.com
Reply
 
Thread Tools
post #1 of 12 Old 03-10-14, 07:15 AM Thread Starter
Shackster
 
Join Date: Feb 2014
Location: Paris, France
Posts: 6
Need help in adjusting acoustics in my home-studio

Hello there!

I am currently trying to adjust the acoustics in my home-studio (mainly for mixing) and need your help to sort out some issues!
It's a 2,30m x 3,70m room (yes, it's metric, please continue reading) with carpet on the floor (about 2-3cm).
Cieling is about 2,40m high. It also has a small space after the door:

(image here)


My monitors are Mackie MR-5 which are quite fair budget-level monitors placed at ear level, driven by a Motu AudioExpress interface.
I measured the response of one of the monitors and it seems quite flat. I am using a Behringer ECM-8000 for measurements.

Facts about the room:
- when clapping your hands, you can hear a clear metallic ringing lasting about 200ms after the clap.
- opening the room door and breaking the small space helps for this, but not completely.
- when bass is playing loud in the room, I cannot hear specific bass resonnance in the small space before the door.

I have tried placing my traps and absorbers in the following matter:

(image here)


wall traps: 1150 x 575 mm, 50 mm thick, 65kg/m3
corner trap: 575 x 575 mm, 100 mm thick, 65kg/m3
foam absorbers: 1000 x 1000 mm, 70 mm thick, quite light (about 20kg/m3)

- wall bass traps are placed about 8cm away from the wall
- foam absorbers are put against the wall
- closet is open on the right side, filled with clothes

The main problems in the room (according to REW measurements) are two persisting bass frequencies: 130Hz and 150Hz that tend to become too present.

Questions:
1. During adjustment, the "wall" bass traps and foam absorbers are not held firmly at 8cm from the wall, they are simply placed on a supporting object:

(image here)


Does this heavily effect the performance of the traps?

2. Changing the traps and absorbers placement had little effect on the room's bass response, for example covering the window with a bass trap or not has very little effect.
What other factors am I overlooking?
I separated the speakers from the desk they are put on by a block of 15cm of foam and made sure the desk was not resonnating/vibrating heavily with bass frequencies.

3. As mentioned earlier, when clapping your hands, you can hear a clear metallic ringing lasting about 200ms after the clap.
What can cause this?

4. Can you suggest a potentially more effective speaker placement?

Thanks for your help

PS: if images don't show, here are the links in order:
http://imgur.com/FaR8Tw7
http://imgur.com/CMKssOZ
http://imgur.com/5C3QkaG

Last edited by boulfad; 03-10-14 at 07:17 AM. Reason: images not showing
boulfad is offline  
Sponsored Links
Advertisement
 
post #2 of 12 Old 03-10-14, 09:54 AM
HTS Senior Moderator
 
bpape's Avatar
Bryan Pape
 
Join Date: Sep 2006
Location: Wildwood, MO (St. Loui
Posts: 5,288
Send a message via AIM to bpape Send a message via Skype™ to bpape
Re: Need help in adjusting acoustics in my home-studio

50mm is going to do very little below a couple hundred Hz. 4" straddling a corner is OK but don't expect it to get down into the last 1.5 octaves. The foam, sorry but pretty much useless unless you want to cut it up into pieces and use high on the walls to help with the slap and flutter.

You would have better luck flipping the setup to face the window wall and keep what's in front of you symmetric left to right. Where you sit will have far more impact than where the speakers are placed - though they can certainly be adjusted to make some improvements.

I am serious... and don't call me Shirley.

Bryan Pape
Lead Acoustician/Owner
Sensible Sound Solutions
bpape is offline  
post #3 of 12 Old 03-10-14, 10:01 AM Thread Starter
Shackster
 
Join Date: Feb 2014
Location: Paris, France
Posts: 6
Re: Need help in adjusting acoustics in my home-studio

Thanks for the info bpape!

I'm using the foam mainly to taim reflections in the mid/high frequencies. Is that useless?
How do you use the foam high on the walls to help with the slap and flutter?

Also, during adjustment, the "wall" bass traps are not held firmly at 8cm from the wall, they are simply placed on a supporting object.
Does this heavily effect the performance of the traps?

Thanks for your help.
boulfad is offline  
 
post #4 of 12 Old 03-10-14, 10:40 AM
HTS Senior Moderator
 
bpape's Avatar
Bryan Pape
 
Join Date: Sep 2006
Location: Wildwood, MO (St. Loui
Posts: 5,288
Send a message via AIM to bpape Send a message via Skype™ to bpape
Re: Need help in adjusting acoustics in my home-studio

Much of what you're hearing with that metallic zine is up high on the walls. Just cut into strips 12-18" and go around the upper perimeter.

Reflections are much broader than just mids and highs, I would never use anything less than 2" fiberglass. Even 4" will do a better job though with more boundary related phase issues in the 100-250hz range.

I am serious... and don't call me Shirley.

Bryan Pape
Lead Acoustician/Owner
Sensible Sound Solutions
bpape is offline  
post #5 of 12 Old 03-17-14, 05:34 AM Thread Starter
Shackster
 
Join Date: Feb 2014
Location: Paris, France
Posts: 6
Re: Need help in adjusting acoustics in my home-studio

Hello,

Thanks for your input guys, I changed my disposition since my first post to something which makes more sense. It also closer to what you guys suggest:
- turned 180 facing the window
- more symmetry.
- use the closet as a bass trap (closet is filled with clothes)

Here is my new disposition:

(image here)


This is how I'm thinking of putting the traps/absorbers. I only possess for now 2 trap panels, the basic foam absorbers and the corner trap.

(image here)


How would you suggest treating the small area at the beginning of the room? Would some sort of thick curtain suffice?

Concerning the hard wood under the speakers, those are positionned on a hard woodden, 2-story desk (with isolation). Would that be enough?
I only have discrete absorbtion issues in mids and highs (a bit at 2kHz and some at 8kHz), but nothing drastic.

Thanks for your help.

PS: images not showing:
http://i.imgur.com/R0sun6Y.jpg
http://i.imgur.com/FbKIzYN.jpg

Last edited by boulfad; 03-17-14 at 05:34 AM. Reason: images not showing
boulfad is offline  
post #6 of 12 Old 03-17-14, 08:40 AM
HTS Senior Moderator
 
bpape's Avatar
Bryan Pape
 
Join Date: Sep 2006
Location: Wildwood, MO (St. Loui
Posts: 5,288
Send a message via AIM to bpape Send a message via Skype™ to bpape
Re: Need help in adjusting acoustics in my home-studio

Skip the foam absorber - not going to do much of anything useful. For the front corners you need to maintain symmetry left to right. 2 flat on the walls in one corner and one straddling in the other will function completely differently.

I am serious... and don't call me Shirley.

Bryan Pape
Lead Acoustician/Owner
Sensible Sound Solutions
bpape is offline  
post #7 of 12 Old 03-17-14, 08:59 AM Thread Starter
Shackster
 
Join Date: Feb 2014
Location: Paris, France
Posts: 6
Re: Need help in adjusting acoustics in my home-studio

Thank you Bryan for your comments.
"Skip the foam absorber - not going to do much of anything useful"
at all?? I am using the foam absorber here mostly to retain some mid/highs from reflecting on the closet door (1/2 inch light wood). Why is that useless?
boulfad is offline  
post #8 of 12 Old 03-17-14, 09:23 AM
HTS Senior Moderator
 
bpape's Avatar
Bryan Pape
 
Join Date: Sep 2006
Location: Wildwood, MO (St. Loui
Posts: 5,288
Send a message via AIM to bpape Send a message via Skype™ to bpape
Re: Need help in adjusting acoustics in my home-studio

It's only dealing with the very very high frequencies. Plus it's only on one side of the rear wall. Still have now unbalanced reflection from the other side.

I am serious... and don't call me Shirley.

Bryan Pape
Lead Acoustician/Owner
Sensible Sound Solutions
bpape is offline  
post #9 of 12 Old 03-17-14, 09:45 AM Thread Starter
Shackster
 
Join Date: Feb 2014
Location: Paris, France
Posts: 6
Re: Need help in adjusting acoustics in my home-studio

Concerning the unbalanced sound, I will place foam on the other side too. I just can't place it permanently or else the closet won't open...
The foam definitely deals with mid frequencies. Changing the place of the 1m foam absorber makes a noticeable difference around 2-5k.
Plus, 5cm is theoretically enough to absorb at least some 3-5k, why wouldn't that apply?
boulfad is offline  
post #10 of 12 Old 03-17-14, 09:51 AM
HTS Senior Moderator
 
bpape's Avatar
Bryan Pape
 
Join Date: Sep 2006
Location: Wildwood, MO (St. Loui
Posts: 5,288
Send a message via AIM to bpape Send a message via Skype™ to bpape
Re: Need help in adjusting acoustics in my home-studio

If you like it, use it. Just saying that most rooms already have considerably more mid/high absorption than they do lower absorption so using things like this just unbalances the decay time spectrum more.

I am serious... and don't call me Shirley.

Bryan Pape
Lead Acoustician/Owner
Sensible Sound Solutions
bpape is offline  
Reply

Bookmarks

Tags
absorbers , acoustics , adjusting , bass , homestudio , traps

Quick Reply
Message:
Options

Register Now




PLEASE COMPLETE ALL REQUIRED FIELDS BELOW... THANKS!

REQUIRED FIELDS ON THIS PAGE
YOU MUST COMPLETE ALL OF THESE

Username
Password
Confirm Password
Email Address
Confirm Email Address
Random Question
Random Question #2




User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
PLEASE READ BELOW PRIOR TO ENTERING AN EMAIL ADDRESS!

ATTENTION!

YOU MUST ACTIVATE YOUR ACCOUNT!

Activation requires you reply to an email we will send you after you register... if you do not reply to this email, you will not be able to view certain areas of the forum or certain images... nor will you be able download software.

AN INVALID EMAIL ADDRESS WILL CAUSE YOUR ACCOUNT TO BE DELETED!

See our banned email list here: Banned Email List

We DO NOT respond to spamcop, boxtrapper and spamblocker emails... please add @hometheatershack DOT com to your whitelist prior to registering or you will get nowhere on your registration.


Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML is not allowed!
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 


For the best viewing experience please update your browser to Google Chrome