VituixCAD

I was worried I wouldn't be able to use this system.

What is "this system", whole VituixCAD or SPL Trace alone? This just reminded me about one message on audiosciencereview.com.
SPL Trace was done to VCAD only because other tools did not work so well or at all. Such a waste if one of the most useless and disrespected part in VCAD (imo) is only feature in use :)
 
Hi kimmosto,

I need some help interpreting the power dissipation graph.:)

Playing with Vituix, I came a up with a design that looks like the following (no idea how many mistakes you can see here, see attachments).

1) Is it normal that there is a lot more power in the tweeter than in the other drivers ? With pink noise, this goes down a lot (the tweeter peak is reduced to 13.8W) but there is still a bit more power than in the other drivers.

2) the maximum power in each driver should never go above the maximum "programme" power rated by the manufacturer, am I right ?

3) same thing for the resistors ?
 

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Hi Kimmo,
Just wondering if you might make the warnings about phase optional on the Merger page as if you are going to output a minimum phase anyway, it would not be of consequence? I was building calibration curves using a mic substitution method and there were a lot of extra clicks to get through. I know that this is not the primary purpose of the page but...
Thanks,
Jay
 
how do l estimate the baffle edge radius of a speaker cabinet that has sides protruding and making a lip, about 4cm in front of the baffle.

That is not supported so 0 mm radius is only option and result is probably not accurate.
Worth to consider much less diffracting construction if HF radiator is not horn. Not much sense to simulate and make that kind of box for small direct radiators.
 
...warnings about phase optional on the Merger page as if you are going to output a minimum phase anyway, it would not be of consequence? I was building calibration curves using a mic substitution method and there were a lot of extra clicks to get through.

No problem to add extra warning about minimum phase export, but lime green phase curve is quite visible and also Minimum phase checkbox is visible so there's already two signals for user that exported phase response will not be the result of division A/B or B/A by Calculator.
 
No problem to add extra warning about minimum phase export, but lime green phase curve is quite visible and also Minimum phase checkbox is visible so there's already two signals for user that exported phase response will not be the result of division A/B or B/A by Calculator.

Thanks Kimmo. I am not sure that I was clear. When I go to import curves without phase (differential curves taken from ARTA between two frequency curves) to the Merger page that have no phase, it gives several warnings. The warnings are what I was wondering about if they could be made optional?
Thanks, Jay
 
^I'm certain that I did not understand your message :D

Is it possible to export from ARTA with phase column or measure reference mic and raw mic separately to get two normal frequency responses with phase?
Separate pir-files could be processed with 'Convert IR to FR' and then coverted to calibration file with Calculator's Divide A/B or B/A function. 'Convert IR to FR' is able to produce minimum phase response for reference mic without phase column in calibration file.

Anyway, VCAD is able to read without phase column and has been able to give only one warning per file, but I haven't checked how Merger behaves and uses that feature.
 
I was doing a microphone calibration by substitution using measured frequency responses farfield and in a nearfield chamber per arta application note 5. It worked out quite well and I have done several tests with almost perfect agreement between the previously calibrated mic and the uncalibrated one. When you subtract curves in arta (divide) by doing an overlay and then subtract from..., it exports a txt file without phase. It is the Merger portion that seems to give several error warnings when I went to save each file after combining and then producing the minimum phase. It is not a big deal but just a little inconvenient.

Thanks so much,
Jay
 
It is the Merger portion that seems to give several error warnings when I went to save each file after combining and then producing the minimum phase. It is not a big deal but just a little inconvenient.

So renaming ARTA's export file to .mic or .cal (instead of .frd or .txt) disables warnings in Merger if you want to divide with ARTA. As already told, Vituix Calculator is able to divide and export with phase. That sounds more ideal, but unfortunately reference mic does not necessarily have measured phase in calibration file.
 
Hi folks, l would like to learn from this forum how l would carry out near field and farfield frequency response measurements for a diy line array cabinet with 2 identical 10 inch drivers and 1.4 inch hi driver with waveguide thats narrows dispersion in the vertical axis, more so if l want to include off_axis measurements. thanks and great regards
 
^Basically all radiator types for all kind of speaker constructions are measured with the same method, described in these two documents:
VituixCAD Measurement Preparations.pdf
VituixCAD_Measurement_Preparations_REW.pdf

Far field measurement distance can be longer than 1000 mm if "acoustic lab" is larger and higher than normal living room.
Near field measurements and conversion to quasi far field with diffraction simulation are not mandatory if anechoic chamber is available.

Documents are talking about multiple woofers and mids as "two woofers/mids" but total number makes no difference.
* All acoustical measurements from one driver for each driver+radiator type.
* Single driver connected to power amplifier while far field measurements.
* All drivers sharing the same box volume connected to amplifier while near field of cone and ports/passives and impedance measurements to get correct result also at LF. Should try to block acoustical signal from other drivers while near field meas. to prevent leak at mid-range which would cause summing error due to phase difference. Impedance result of multiple drivers should be scaled (with the simulator) to represent single driver because schematic of simulator builds speaker from multiple single drivers.

This is universal method for all XO simulators using measurement data, not for some individual tool such as VCAD.