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Share your in-room measurements?

thefsb

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Would it be useful to have a forum thread where we can gather people's in-room frequency response measurements and discuss them? Those who did something to improve their sound based on measurements might also describe what they did and show the results. I think this could be quite interesting. What do you think?
 

Sancus

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QMuse

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Ok, let's start. Uncorrected, measured at LP, 4 meters from speakers, MMM RTA with pink noise, 1/6 smoothing:

Capture.JPG


Same, but corrected actual response:

Capture1.JPG
 

Blumlein 88

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Just because it is what I have handy to display. Here is the uncorrected result for LSR305's when I was using them for front speakers in my video system. Never corrected them as it was a temporary arrangement. Red is at the LP, and green is a 6 position average for a square meter around the LP. 1/6th smoothing.

Maybe we should discuss which type of smoothing to use. I think 1/6th is generally good to more or less equal what our ears hear and showing a useful amount of detail. Though perhaps psychoacoustic in REW is even better. I wonder about the psychoacoustic smoothing in REW below 200 hz however.

1590183417224.png
 
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QMuse

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Just because it is what I have handy to display. Here is the uncorrected result for LSR305's when I was using them for front speakers in my video system. Never corrected them as it was a temporary arrangement. Red is at the LP, and green is a 9 position average for a square meter around the LP.

Did I have a glass of wine too much or something is missing here? :D
 

Blumlein 88

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Here is the average with psychoacoustic in orange and 1/6th smoothing in green.

1590183830118.png


Here is the same comparison with only the LP measurement. Looks like spatial averaging gets you very close to psychoacoustic smoothing. While single point measurements are more different between 1/6th and psychacoustic smoothing. Psychoacoustic is blue, and 1/6 th is red.

1590184121778.png
 

QMuse

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Just because it is what I have handy to display. Here is the uncorrected result for LSR305's when I was using them for front speakers in my video system. Never corrected them as it was a temporary arrangement. Red is at the LP, and green is a 9 position average for a square meter around the LP. 1/6th smoothing.

Maybe we should discuss which type of smoothing to use. I think 1/6th is generally good to more or less equal what our ears hear and showing a useful amount of detail. Though perhaps psychoacoustic in REW is even better. I wonder about the psychoacoustic smoothing in REW below 200 hz however.

View attachment 64845

This is very impressive for uncorrected response - you must have a really "calm" room. :)
 

Blumlein 88

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This is very impressive for uncorrected response - you must have a really "calm" room. :)

The room is a little too reflective, but is large. It is 19.5 ft wide (5.9 m) , 33.3 ft long (10.1) and 10 ft. (3 m) ceiling.
 

QMuse

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The room is a little too reflective, but is large. It is 19.5 ft wide (5.9 m) , 33.3 ft long (10.1) and 10 ft. (3 m) ceiling.

Too reflective?!? You should see mine - it is 5m * 8.5m, but much more "lively" than yours. Still sounds good though. :)
 

Blumlein 88

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This might be worth showing. Orange is the 6 measurement average around the LP, and cyan is the single point sweep at the LP. Both are un-smoothed. You can see just how much smoothing of the numerous reflections gets filtered out by doing measurements in several locations. I've not done much MMM yet, I would think they'd smooth it out even more.
1590188563567.png




And here is the spatial average measurement without smoothing in orange and with pscyhoacoustic smoothing in blue.
1590188493781.png


Still seems incredible magic we can do such analysis with free software, a $100 microphone and a computer.

EDIT: to fix having the wrong screenshots shown. Correct shots are there now.
 
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Duckeenie

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My speakers are desk mounted and sandwiched between two bookcases. I should probably stick to headphone listening really. Oddly enough to my ears the system sounds a little bright. Measurements don't support that though. This hobby will drive you mad if you let it.
roomeq.jpg


Haven't managed to find a correction I can live with yet. I don't know whether I just got used to the sound as is or what I hear isn't what the Mic hears.
 

Daverz

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Vandersteen Quatros (original cloth version) with the subwoofer level and all 11 EQ pots set to the zero position, 1/6 octave smoothing:

quatro-flat.jpg


Then with REW rePhase EQ applied up to 200 Hz. (Not shown: I cranked up the subwoofer level to make the dip between 100 and 200 Hz easier to fill in.)

quatro-rephase.jpg
 

Matias

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Before and after the PEQ in the window.
1-1.PNG
 
OP
thefsb

thefsb

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Vandersteen Quatros (original cloth version) with the subwoofer level and all 11 EQ pots set to the zero position, 1/6 octave smoothing:

View attachment 64864

Then with REW rePhase EQ applied up to 200 Hz. (Not shown: I cranked up the subwoofer level to make the dip between 100 and 200 Hz easier to fill in.)

View attachment 64865
Impressive. I'd be interested to know how well this kind of correction works over a range of listening positions.
 
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thefsb

thefsb

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I don't know no but a thread where everyone shares their in room measurements will be good and this can be it.
Oh boy. Buying a mic and learning to use REW and making good repeatable measurements and understanding the data and doing something about it... this is not going to be a distraction from my guitar practice, is it?
 
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