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VituixCAD v2 released

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  • kimmosto
    replied
    Originally posted by dkalsi View Post
    The simulated response DOES match measured response if I don't load or enable the mic calibration file in ARTA.
    That's correct. If you wan't to look or compare measured frequency responses with ARTA, you need to load and enable calibration file also in ARTA.

    PS. This kind of comparison procedure is not included in my measurement prep. instruction because simulation is typically more accurate within 20-20kHz than home measurement of complete speaker. No harm to make some sanity checks and verify that basic things such as polarities and levels are equal to simulation.

    Originally posted by dkalsi View Post
    Does this mean that the approach detailed in the "Preparation of response measurements" will not work for any mic that requires a calibration file?
    No. See previous answer.

    Originally posted by dkalsi View Post
    ...there was this one additional step where one was supposed to view the tweeter's measured phase and minimum phase... Is that step no longer necessary?
    Not needed anymore. Clicking of Far 1 button (and possible fine tuning of Reference time in ms) in Convert IR to FR tool makes the same trick ie sets Reference time to peak of tweeter's IR.
    Last edited by kimmosto; 12-30-2018, 11:33 AM.

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  • dkalsi
    replied
    Originally posted by kimmosto View Post
    ^You can load and enable mic cal file also in ARTA, but that does not have any effect if frequency responses are finally exported with VituixCAD Convert IR to FR tool.
    I guess this is where I get stuck.

    I've taken measurements in ARTA (via the semi-dual method), and had loaded and enabled the mic calibration file for all my raw driver measurements. I then saved all files in ARTA's native *.pir format.

    Followed all the directions for VituixCAD's new "Preparing of response measurements" and did all the processing for near/far-field measurements as recommended in the document.

    When I model a crossover, the VituixCAD simulated response DOES NOT match the measured response when measuring with ARTA with the calibration file enabled. The simulated response DOES match measured response if I don't load or enable the mic calibration file in ARTA.

    Is this what you meant when you said: "does not have any effect if frequency responses are finally exported with VituixCAD"?

    See the attached image.

    RED = Simulated Response from VituixCAD
    GREEN = Measured Response from ARTA with Mic Calibration File Enabled
    BLUE = Measured Response from ARTA with Mic Calibration File Disabled.

    As you can see, the RED and GREEN are nearly on top of one another (disregard response below 1.8K).

    Does this mean that the approach detailed in the "Preparation of response measurements" will not work for any mic that requires a calibration file?


    Also - in the previous Preparation document, there was this one additional step where one was supposed to view the tweeter's measured phase and minimum phase, and add the delay necessary that would cause the measured phase to match as close as possible to minimum phase. Then that same delay value would need to be updated for every driver in the the speaker (i.e., mid-woofer, woofer). Is that step no longer necessary?


    Click image for larger version

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  • kimmosto
    replied
    ^You can load and enable mic cal file also in ARTA, but that does not have any effect if frequency responses are finally exported with VituixCAD Convert IR to FR tool.

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  • dkalsi
    replied
    Originally posted by kimmosto View Post
    ^

    3) Microphone response compensation is done in the application which converts impulse responses to frequency responses with FFT. That application is now VituixCAD.
    Got it - does that mean one should not load the Microphone Calibration file into ARTA before taking measurements?

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  • kimmosto
    replied
    ^
    1) Yes. Measurement program just measures and saves impulse responses to ARTA PIR or CLIO MLS files. Everything else is done with VituixCAD.

    2) Measurement files will contain measured phase. Minimum phase checkbox is for microphone calibration file only.

    3) Microphone response compensation is done in the application which converts impulse responses to frequency responses with FFT. That application is now VituixCAD.

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  • dkalsi
    replied
    Originally posted by kimmosto View Post
    Rev. 2.0.5.9 (2018-11-17)

    Convert IR to FR
    * Added 'Far 1' button to set default values for the 1st far field export (tweeter's).
    * Added 'Near' button to set default values for near field export.
    * See Preparation of response measurements for crossover simulation with VituixCAD for more information.
    So I just read through the new "Preparation of response measurements for crossover...." document and I have few questions.

    Before I begin, just wanted to mention I'm new to speaker measurements and design.

    The questions:

    1) Is all "gating" performed in VituixCAD now? In the old version of the document, I remember it suggesting to first take measurement of the mid-woofer/woofer 80-degrees off axis to set the beginning marker of the gating . And all subsequent measurements would then be based on the same gating marker, which I assume was then help maintain the relative timing difference between different drivers.

    2) Once processing the files based on the new document, do the output files all contain "minimum phase" (as opposed to measured phase)? I'm looking at the bottom of Page 5 of the document, where it states: "Check Minimum Phase if you want to compensate missing phase response of calibration file". Or is this referring to the microphone calibration file loaded in the immediately preceding step.

    3) I don't think the older version of the document mentioned anything about loading the microphone calibration file. I know ARTA allows one to load in the microphones calibration file prior to taking measurements.

    Thanks,
    D





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  • kimmosto
    replied
    Rev. 2.0.5.9 (2018-11-17)

    Convert IR to FR
    * Added 'Far 1' button to set default values for the 1st far field export (tweeter's).
    * Added 'Near' button to set default values for near field export.
    * See Preparation of response measurements for crossover simulation with VituixCAD for more information.

    Leave a comment:


  • kimmosto
    replied
    ^I already tested default buttons and noticed that left window should be much longer than original value in the pdf. For example 15" PA coaxial might need 320 mm left window due to depth of tweeter's acoustic center. 18" woofer need at least 200 mm for near field due to shallow impulse.
    Buttons will be in the next revision.

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  • kimmosto
    replied
    Thanks!
    One possibility is to add two small default buttons to help setup. Sequence would be:
    1: open all tweeter's far field, click FF1 button, set left window, adjust right window, export
    2: open all mid's far field, adjust right window, export
    3: open all woofer's far field, adjust right window, export
    4: open all near field, click NF button, export
    done
    maybe too easy

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  • civit
    replied
    Originally posted by kimmosto View Post
    Preparation of response measurements for crossover simulation with VituixCAD updated for Convert IR to FR tool i.e. measurements are done with ARTA or Clio, and frequency responses are converted from pir/mls to txt/frd with VituixCAD. Refresh pdf to see the latest.
    Kimmo that's a huge update. Incredible work.

    Leave a comment:


  • RBG
    replied
    Thank you so much for your amazing job!

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  • kimmosto
    replied
    Preparation of response measurements for crossover simulation with VituixCAD updated for Convert IR to FR tool i.e. measurements are done with ARTA or Clio, and frequency responses are converted from pir/mls to txt/frd with VituixCAD. Refresh pdf to see the latest.

    Leave a comment:


  • jmb
    replied
    As Willy Wonka said (the original), "A little foolishness now and then, is relished by the wisest of men".
    Jay

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  • kimmosto
    replied
    Originally posted by civit View Post
    Kimmo, apologies if you've answered this 100 times, but what does Vituix mean?
    Actually you're the first one who is asking this on any discussion forum. All native Finnish know that for sure. There's no direct translation to any other language because "vituix" is originally dialect word "vituiks", "vituiksi", "vituralleen" or "päin vittua" written in urban/teenage format where "ks" has been replaced with "x". It is bad language - the worst one of the following: "bitch up", "mess up", "f**k up" or "screw up". Superhero in my avatar is "Vituixman" which is dialect abbreviation from "meni vituiksi" = * was screwed up. It's parody from Superman by DC Comics. Dialog is modified over the original graphics by unknown Finnish author. That anti-hero screws up everything he touch.

    So the name VituixCAD is just childish or bad local humor which is not okay for everyone. But this hobby should not be too serious.

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  • civit
    replied
    Originally posted by mmu7 View Post
    Unrelated.. but I wish some of these software were open-source. It would be an interesting project to write an optimization/learning algorithms to identify optimal crossover/drivers combos (something I'd love to do as a spare project).
    Vituixcad has some of this functionality, and it works pretty well. LSPCad had a simpler version of it. Selecting driver combos is still very much a manual process.

    Leave a comment:

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