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How to make quasi-anechoic speaker measurements/spinoramas with REW and VituixCAD

Sokel

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Port measurement is loaded to "low frequency part" of merge tool. See measurement guide and manual section for merge tool.
I think I'm getting there (slowly,first time I do this! ) ,thanks!

Port.PNG

Thanks to the author,amazing program.
 

Dave Bullet

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@Sokel I presume your 3 way (if non-theoretical) is using a non-waveguided tweeter on a flat baffle with power response "bunching" around 2 - 5KHz? This may increase apparent in room brightness. You may want to explore waveguides. I've encountered some good improvements in directivity using a waveguide as shown (top set = SB26ADC no waveguide, bottom = SB26ADC in a Visaton WG148R). It's made for a much smoother power response. The waveguide helps ameliorate the peak dip one often sees with conventional baffle geometry on a tweeter.

PS: Ignore the upper frequency ripple in the top set of measurements. This is an artefact of my mic boom/clip setup (fixed with the bottom set).
1705637053410.png
 

Sokel

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@Sokel I presume your 3 way (if non-theoretical) is using a non-waveguided tweeter on a flat baffle with power response "bunching" around 2 - 5KHz? This may increase apparent in room brightness. You may want to explore waveguides. I've encountered some good improvements in directivity using a waveguide as shown (top set = SB26ADC no waveguide, bottom = SB26ADC in a Visaton WG148R). It's made for a much smoother power response. The waveguide helps ameliorate the peak dip one often sees with conventional baffle geometry on a tweeter.

PS: Ignore the upper frequency ripple in the top set of measurements. This is an artefact of my mic boom/clip setup (fixed with the bottom set).
View attachment 342996
Thanks for the advice but I can't change much,it's a ready speaker which I only tried to simulate as I like to practice and see.
It's not flat baffle but no waveguided either.

It's in room looks like this. in MLP.
 

Rick Sykora

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Thanks for the advice but I can't change much,it's a ready speaker which I only tried to simulate as I like to practice and see.
It's not flat baffle but no waveguided either.

It's in room looks like this. in MLP.

yes, looks quite good to me. Need to adjust to 50 dB scale and will look much better.:)
 

Sokel

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yes, looks quite good to me. Need to adjust to 50 dB scale and will look much better.:)
I made it so it can fit all three levels the 30Hz room mode I have,there's a fresh one with EQ and without:

50 scale.PNG

(I left a little bit of the 30s,as a guilty pleasure)
 

Rick Sykora

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I made it so it can fit all three levels the 30Hz room mode I have,there's a fresh one with EQ and without:

View attachment 343078

(I left a little bit of the 30s,as a guilty pleasure)

Sorry, but the scale on the measurement was fine. It is the VCAD sim that was twice the scale that is typical.
 

Sokel

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The Vcad is 50 to 90db,do I have to scale it less?
I just used the defaults I think,totally newbie to it!

I see what I can do.
 

Dave Bullet

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What mic are
Trying to simulate some speakers I have here and finding no other way to add the port,I measured it nearfield (very),I did the whole proses,etc and added it as a driver.
Is it right or wrong?Is there another way?

View attachment 326263 View attachment 326264

The quasi anechoic measurement procedure I use is
1. Measure port nearfield
2. Measure woofer nearfield
3. Scale port down to match woofer
4. Merge
5. Apply baffle diffraction to merged near field response
6. Merge baffle diffraction nearfield with gated Fairfield

I can break this down further if useful. Also some variation of multiple woofers are in circuit

Having said all that the procedure documented in this very thread is the same
 

ppataki

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I really appreciate this tutorial - I have decided to give it a try but I got stuck when exporting all the IRs from REW

When I click here:
1708003409442.png


I do not get the same Export window that I shall; like this one:
image3.png


But this one instead:

1708003474609.png


So I just hit export but when I try to import these in VituixCAD I get the below error message:

1708003515619.png


Can anybody please advise?

FYI @ernestcarl
Thank you
 
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I really appreciate this tutorial - I have decided to give it a try but I got stuck when exporting all the IRs from REW

When I click here:
View attachment 349734

I do not get the same Export window that I shall; like this one:
image3.png


But this one instead:

View attachment 349736

So I just hit export but when I try to import these in VituixCAD I get the below error message:

View attachment 349737

Can anybody please advise?

FYI @ernestcarl
Thank you
I've only found success in exporting every measurement singularly, and renaming them to match the needed syntax for Vcad.
 
OP
N

napilopez

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I really appreciate this tutorial - I have decided to give it a try but I got stuck when exporting all the IRs from REW

When I click here:
View attachment 349734

I do not get the same Export window that I shall; like this one:
image3.png


But this one instead:

View attachment 349736

So I just hit export but when I try to import these in VituixCAD I get the below error message:

View attachment 349737

Can anybody please advise?

FYI @ernestcarl
Thank you

Did you try clicking "Export all measurements as text?" instead of Export all impulse responses?
 
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