Impulse responses - Home Theater Forum and Systems - HomeTheaterShack.com

Reply
 
Thread Tools
post #1 of 15 Old 07-06-16, 06:24 PM Thread Starter
Shackster
 
Join Date: Feb 2013
Posts: 11
Impulse responses

Hello everybody. I did some impulse response measurements in my music room. It's a room mainly dedicated to teaching activities, and I'd like to make it sound as good as I can. I made a QRD Schroeder diffuser, placed in the middle of the roof, and now I'd like to understand what I can do to improve the acoustics. I attach the drawings of the room with the source and receivers, and measurements from source in A and receiver 1.
Hints from the experts are very welcome !
Moreover I don't quite understand the reason why the spl response at, let's say, 1000 Hz, is higher than it is at 2000 Hz, but the rt at 1000 Hz is lower than rt at 2000 Hz. I think: higher spl>lower damping>longer decays but something is missing...
Schroeder frequency should be 140 Hz.
Attached Thumbnails
Impulse responses-measurement_a1_wf.jpg  

Impulse responses-measurement_a1_spl.jpg  

Impulse responses-measurement_a1_rt60.jpg  

Impulse responses-misure.jpg  

angeloconto is offline  
Sponsored Links
Advertisement
 
post #2 of 15 Old 07-07-16, 02:39 AM
Senior Shackster
lesmor
 
Join Date: Dec 2009
Posts: 153
Re: Impulse responses

Unfortunately the scale of your graphs are not as recommended on the REW site for posting
I think you need to supply more detail on the sources that seem to be scattered around the room
Also are the room dimensions in metric?
Please supply the room lenght,width and Height
It is also better to attach the metadata files for someone to look at
lesmor is offline  
post #3 of 15 Old 07-07-16, 09:14 AM Thread Starter
Shackster
 
Join Date: Feb 2013
Posts: 11
Re: Impulse responses

Hi Lesmor,
yes the measures are in metric, and we have to subtract some 30 cm because of the insulation. So they are: lenght 10,63 m, width 5,39 m, heigh 2,8 m.
I recorded the impulse response placing the source (Genelec 8040) in the various positions I drawn on the plan.
About the graphs: I upload this new graphs, hoping it will be better. What metadata are ?
angeloconto is offline  
 
post #4 of 15 Old 07-07-16, 09:15 AM Thread Starter
Shackster
 
Join Date: Feb 2013
Posts: 11
Re: Impulse responses

graphs
Attached Thumbnails
Impulse responses-measurement_a1_wf.jpg  

Impulse responses-measurement_a1_spl_2.jpg  

Impulse responses-measurement_a1_rt60.jpg  

angeloconto is offline  
post #5 of 15 Old 07-07-16, 10:25 AM
Senior Shackster
lesmor
 
Join Date: Dec 2009
Posts: 153
Re: Impulse responses

Quote:
angeloconto wrote: View Post
Hi Lesmor,
yes the measures are in metric, and we have to subtract some 30 cm because of the insulation. So they are: lenght 10,63 m, width 5,39 m, heigh 2,8 m.
I recorded the impulse response placing the source (Genelec 8040) in the various positions I drawn on the plan.
About the graphs: I upload this new graphs, hoping it will be better. What metadata are ?
Hi angeloconto
The metadata is your REW files which you can add as an attachment
This will allow people to view and manipulate the data on their own copy of REW
To be clear I am no expert just trying hopefully to point you in the right direction
I am sure someone with more experience will eventually come and in and advise you.
lesmor is offline  
post #6 of 15 Old 07-07-16, 01:43 PM Thread Starter
Shackster
 
Join Date: Feb 2013
Posts: 11
Re: Impulse responses

Ok, I have attached the rew files. Looking forward for some hint !
Attached Files Klang_A1.mdat (9.67 MB) 
angeloconto is offline  
post #7 of 15 Old 07-07-16, 01:54 PM
Senior Shackster
lesmor
 
Join Date: Dec 2009
Posts: 153
Re: Impulse responses

Quote:
angeloconto wrote: View Post
Ok, I have attached the rew files. Looking forward for some hint !
Thanks
Have you ever considered contacting GIK Acoustics?
They will look at your space and data and offer free advice.
lesmor is offline  
post #8 of 15 Old 07-07-16, 02:12 PM
Senior Shackster
lesmor
 
Join Date: Dec 2009
Posts: 153
Re: Impulse responses

@angeloconto
Had a quick look at the data
I am in no way a expert

What SPL did you set for the measurement as it looks to be too low?
What microphone are you using?
The Graph seems to roll off at 70 Hz is that the -3db cut off of the source if so there is no usable bass data.
Looking at the impulse response there seems to be a lot of reflections.
Sorry for all the questions but just trying to get a feel of what you are actually looking for.
lesmor is offline  
post #9 of 15 Old 07-07-16, 02:51 PM Thread Starter
Shackster
 
Join Date: Feb 2013
Posts: 11
Re: Impulse responses

Hi Lesmor,
I didn't set a reference level for spl, just check that the level was ok for rew
mic: Dayton 8098 with calibration file
the lower cutoff frequency of Genelec 4080 from technical spec is 45 Hz
angeloconto is offline  
post #10 of 15 Old 07-07-16, 03:21 PM
Senior Shackster
lesmor
 
Join Date: Dec 2009
Posts: 153
Re: Impulse responses

Quote:
angeloconto wrote: View Post
Hi Lesmor,
I didn't set a reference level for spl, just check that the level was ok for rew
mic: Dayton 8098 with calibration file
the lower cutoff frequency of Genelec 4080 from technical spec is 45 Hz
From what I can gather your readings are too low.
What is the noise floor of your room?
In the meantime perhaps have a look at this video


lesmor is offline  
Reply

Bookmarks

Tags
impulse , responses

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