What does room response mean and how do you measure it?

[haroon08]

hey guys.. total newbie here. I have a Pioneer VSX-52 reciever, (2) definitive technology 8060st towers, and a HSU VTF-15H subwoofer. I set it up just using the auto calibration (MCAAC) on my reciever.

I see a lot of people showing graphs of their "room response" and talking about how a flat response is a good thing. Can someone please explain to me what room response is, how do I check mine, and what needs to be done to improve it? Thanks in advance!!!

 

[Tom V.]

They are referring to the frequency response of the speakers and/or subwoofer as measured at the seating positions. In a nutshell---the frequency response will tell you if the output of the speaker/subwoofer is being adversely affected by the room boundaries. A well designed speaker/subwoofer will have a relatively flat response curve if measured outside(or in an anechoic chamber---free of any reflections). But once you place them in a room the acoustical output is often altered(sometimes grossly) by interaction with the walls,floor,ceiling.

You can google "room mode" and learn more about that.

Tom V.

 

[bread29]

As far as I know, room response is measuring the In-room frequency curve of your speakers and sub. Many use Room EQ Wizard:

REW - Room EQ Wizard Home Page

This requires a computer w/decent sound card and microphone.

 

[Matt34]

This is probably the easiest method of measuring your room response.

Dayton Audio OmniMic V2 Precision Audio Measurement System 390-792

Here is a great reference book on understanding the basis behind having a nice flat FR.

Amazon.com: Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms (9780240520094): Floyd Toole: Books

 

[haroon08]

As far as I know, room response is measuring the In-room frequency curve of your speakers and sub. Many use Room EQ Wizard:

This requires a computer w/decent sound card and microphone.

Thanks for the help! good info here

BTW.. how do you like your MBM 12?

 

[bread29]

No problem, and welcome to the forum. I do like the MBM and feel it accents the VTF3 when set up properly. Many will say it's unnecessary as long as you have 2 good subs, but I paid $$ for it and I'm not being talked out of liking it .

 

[haroon08]

This is probably the easiest method of measuring your room response.

Dayton Audio OmniMic V2 Precision Audio Measurement System

Here is a great reference book on understanding the basis behind having a nice flat FR.

Have you used the omnimic? does it only give measurements or does it "fix" the response also? Thanks for the link to the book! Im gonna check that out!

 

[BoredSysAdmin]

Have you used the omnimic? does it only give measurements or does it "fix" the response also? Thanks for the link to the book! Im gonna check that out!

Omnimic doesn't fix anything - it measures and can produce file with corrections needed.. You need some sort of PEQ to apply these...
Most people use MiniDSP or Behringer's BFD for that purpose... that also means you must separate processing and amp, since PEQ goes right in between them

 

[ski2xblack]

BSA is absolutely correct, but the Dayton kit can aid in optimizing sub placement and crossover settings, even in a system that cannot incorporate DSP/correction trickery. It's a tremendous help to know what's really going on in your room, and to be able to compare different locations/settings for optimum results. It's pretty expensive as strictly a measuring tool, but useful.

 

[haroon08]

Omnimic doesn't fix anything - it measures and can produce file with corrections needed.. You need some sort of to apply these...
Most people use that purpose... that also means you must separate processing and amp, since PEQ goes right in between them

geez looks like you almost have to spend half of your budget on calibration tools as you do on your equipment! great stuff guys. I appreciate the info.

 

[BoredSysAdmin]

geez looks like you almost have to spend half of your budget on calibration tools as you do on your equipment! great stuff guys. I appreciate the info.

it doesn't have to be expensive.. you can use cheap Radioshack SPL meter as your microphone - it's not super precise, but enough to give you more than general idea.. and it's only about $50 (REW is able compensate for RS SPL meter imperfections)

Rew EQ software is Free...

Like ski2xblack correctly mentioned - the measurements still could be used for speakers positioning and/or adding room treatments

But yea - got the get that final easy process of pin point fixing issues with PEQ you'd need to spend a bit more on electronics, which still btw you should do AFTER you found best position for speakers AND did room treatments.

 

[haroon08]

it doesn't have to be expensive.. you can use cheap Radioshack SPL meter as your microphone - it's not super precise, but enough to give you more than general idea.. and it's only about $50 (REW is able compensate for RS SPL meter imperfections)

Rew EQ software is Free...

Like ski2xblack correctly mentioned - the measurements still could be used for speakers positioning and/or adding room treatments

But yea - got the get that final easy process of pin point fixing issues with PEQ you'd need to spend a bit more on electronics, which still btw you should do AFTER you found best position for speakers AND did room treatments.

Would you recommend getting a radio shack SPL meter or something like a behringer ecm8000 to use as my microphone? If I have the microphone and use the REW software do I still need a SPL meter?