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Room Measurement Tutorial for Dummies Part 2

RayDunzl

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Sal1950

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How do you really learn how to do anything other than by doing it?
You told me the same once and I was not pleased. New users are looking for a little more step by step guidance and have some fear of the unknown. REW can be a daunting prospect for the beginner and due to it's power can be very confusing.
Just fool with it till you break something, then ask for help, isn't the best choice of advice. IMHO
The good news is there's tons of other info available, maybe the better approach is to point them to it. ;)
 
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You told me the same once and I was not pleased. New users are looking for a little more step by step guidance and have some fear of the unknown. REW can be a daunting prospect for the beginner and due to it's power can be very confusing.
Just fool with it till you break something, then ask for help, isn't the best choice of advice. IMHO
The good news is there's tons of other info available, maybe the better approach is to point them to it. ;)
Thank you sir. Also, for other newbies like myself in the same situation, I found a very useful piece on the Roon forum. Here is the URL: https://community.roonlabs.com/t/a-guide-how-to-do-room-correction-and-use-it-in-roon/23800

The only problem is that this, and other guides talk about connecting to an HDMI port on the receiver. However, what does one do if one has invested in an old fashioned two channel amp, with no HDMI, or indeed any digital inputs? I plan to connect my MacBook running REW to a DAC, which will connect to one of the spare analog inputs into the AMP. Whether or not this works I'll see when the measuring mike arrives. I'll post again to help other newbies when I discover whether or not this strategy works.
 

RayDunzl

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The only problem is that this, and other guides talk about connecting to an HDMI port on the receiver.
HDMI is not required.

I plan to connect my MacBook running REW to a DAC, which will connect to one of the spare analog inputs into the AMP.
If you can play music from the computer through the DAC you should be able to get that path to work for REW to send test tones.

I haven't had a Mac for 20 years so can't help you there.
 
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Thank you. This is very good news indeed. I am looking forward to experimenting with all this when the mike comes. Thanks to this thread for getting me started on this adventure.
 

RayDunzl

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Figure out how to send tones to the speakers now.

Then, when you get your mic, you'll already have that behind you.

You'll use the Preferences - Soundcard tab to set up the output

Generator - to send some noises
 
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I recently bought iLoud Micro for my desktop PC.

Got measurements on REW from UMIK-1, using the calibration file. Left all "hardware" equalization off on the speakers and this is what I got:

1600639618272.png


I'm using variable smoothing as that's suggested for equalizing stuff.

Now, I've then done some experiments on generating equalization filters and this is what I get as a result:

1600640114774.png


It takes care of the boominess I was hearing but I'm left wondering if it's normal that it basically ignores all the frequencies higher than about 900Hz, no matter what I tell REW to do in "Match Range" input fields. That dip at 1.2KHz looks kind of worrying. Do I worry for nothing and this is normal behavior?

These are the filters it generates (which I use with EqualizerAPO):

Filter 1: ON PK Fc 219 Hz Gain -21.9 dB Q 2.296
Filter 2: ON PK Fc 108 Hz Gain -25.2 dB Q 2.561
Filter 3: ON PK Fc 120 Hz Gain 10.6 dB Q 2.093
Filter 4: ON PK Fc 79.4 Hz Gain 18.0 dB Q 3.801
Filter 5: ON PK Fc 219 Hz Gain 18.0 dB Q 5.000
Filter 6: ON PK Fc 255 Hz Gain 11.3 dB Q 5.000
Filter 7: ON PK Fc 501 Hz Gain -3.2 dB Q 1.011
Filter 8: ON PK Fc 267 Hz Gain -10.4 dB Q 5.000
Filter 9: ON PK Fc 58.7 Hz Gain -12.2 dB Q 4.306
Filter 10: ON PK Fc 294 Hz Gain 10.4 dB Q 5.000
Filter 11: ON PK Fc 294 Hz Gain 10.4 dB Q 5.000
Filter 12: ON PK Fc 332 Hz Gain -7.0 dB Q 5.000
Filter 13: ON PK Fc 160 Hz Gain 11.0 dB Q 12.918
Filter 14: ON PK Fc 450 Hz Gain -3.5 dB Q 5.000
Filter 15: ON PK Fc 397 Hz Gain 3.5 dB Q 5.000
Filter 16: ON PK Fc 496 Hz Gain 2.1 dB Q 5.000
Filter 17: ON PK Fc 76.8 Hz Gain -3.1 dB Q 11.740
Filter 18: ON PK Fc 168 Hz Gain -0.1 dB Q 8.780
Filter 19: ON PK Fc 144 Hz Gain -1.1 dB Q 11.938
Filter 20: ON PK Fc 73.6 Hz Gain 0.7 dB Q 11.665
 

ezra_s

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I recently bought iLoud Micro for my desktop PC.

Got measurements on REW from UMIK-1, using the calibration file. Left all "hardware" equalization off on the speakers and this is what I got:

View attachment 83947

I'm using variable smoothing as that's suggested for equalizing stuff.

Now, I've then done some experiments on generating equalization filters and this is what I get as a result:

View attachment 83949

It takes care of the boominess I was hearing but I'm left wondering if it's normal that it basically ignores all the frequencies higher than about 900Hz, no matter what I tell REW to do in "Match Range" input fields. That dip at 1.2KHz looks kind of worrying. Do I worry for nothing and this is normal behavior?

These are the filters it generates (which I use with EqualizerAPO):

Filter 1: ON PK Fc 219 Hz Gain -21.9 dB Q 2.296
Filter 2: ON PK Fc 108 Hz Gain -25.2 dB Q 2.561
Filter 3: ON PK Fc 120 Hz Gain 10.6 dB Q 2.093
Filter 4: ON PK Fc 79.4 Hz Gain 18.0 dB Q 3.801
Filter 5: ON PK Fc 219 Hz Gain 18.0 dB Q 5.000
Filter 6: ON PK Fc 255 Hz Gain 11.3 dB Q 5.000
Filter 7: ON PK Fc 501 Hz Gain -3.2 dB Q 1.011
Filter 8: ON PK Fc 267 Hz Gain -10.4 dB Q 5.000
Filter 9: ON PK Fc 58.7 Hz Gain -12.2 dB Q 4.306
Filter 10: ON PK Fc 294 Hz Gain 10.4 dB Q 5.000
Filter 11: ON PK Fc 294 Hz Gain 10.4 dB Q 5.000
Filter 12: ON PK Fc 332 Hz Gain -7.0 dB Q 5.000
Filter 13: ON PK Fc 160 Hz Gain 11.0 dB Q 12.918
Filter 14: ON PK Fc 450 Hz Gain -3.5 dB Q 5.000
Filter 15: ON PK Fc 397 Hz Gain 3.5 dB Q 5.000
Filter 16: ON PK Fc 496 Hz Gain 2.1 dB Q 5.000
Filter 17: ON PK Fc 76.8 Hz Gain -3.1 dB Q 11.740
Filter 18: ON PK Fc 168 Hz Gain -0.1 dB Q 8.780
Filter 19: ON PK Fc 144 Hz Gain -1.1 dB Q 11.938
Filter 20: ON PK Fc 73.6 Hz Gain 0.7 dB Q 11.665
perhaps you allowed narrow filters in low freq so most filtering go there. Also it is better to sort the eq list by Hz so they can be read easier
 
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perhaps you allowed narrow filters in low freq so most filtering go there. Also it is better to sort the eq list by Hz so they can be read easier
Ok, so... something similar happened to me three years ago. I had been told that my target level was too high for REW to calculate filters for high frequencies. And, in fact, if I lower target level from 75db to 73db it smooths out the all spectrum. I wonder, maybe I should use the -3db bass switch on the speakers, in order to have basses less overpowering?
 

vavan

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no matter what I tell REW to do in "Match Range" input fields
and what "Max boost" value you used? I guess rew is just out of gas to pull out such a dip
 
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and what "Max boost" value you used? I guess rew is just out of gas to pull out such a dip
I managed to get it flat by increasing the max boost and remeasuring. But they honestly don't sound good, even if EQ curve says otherwise.

The measures I'm taking are very far from what I read here: http://noaudiophile.com/IK_Multimedia_iLoudMM/

So now I've ordered two stands for them and I am curious to see whether they measure better mounted on stands and they EQ better too.
 
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Maybe your ears just need more time?
It's not that, I've got Sennheiser HD800 in the same listening position. They're equalized to the Harman curve. Equalizing the highs makes everything sound wrong and shrill. By limiting EQ to bass frequencies the sound is much closer to that of the headphones (and I'm talking about the highs, mainly, I know Harman curve emphasizes bass a bit).
 
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