VituixCAD v2

[witwald]

For your consideration, I would like to ask that a new feature be added to VituixCAD's Enclosure simulation tool.

Often when I am performing an enclosure analysis/study, I find it is useful to know the dB/octave slope of a curve at various points. The cursor already has the facility to display the (Hz, dB, phase) associated with any given point on the chosen curve.

Would it be possible to also display the local slope of the curve in dB/octave?

Thank you for considering my feature request.

[kimmosto]

2.0.126.0 (2025-06-06)

Main

• Added 'Clean user.config' command to Help menu.

Enclosure

• Added Quasi-Chebyshev alignment to Align tab.

[kimmosto]

Perhaps VituixCAD could do some automatic cleanup, only retain config file for last version or something to that effect.

This is already done and tested, but single 'Yes to all' button would be faster than 90 times Yes 😀. Standard message box does not have Yes to all so it requires custom window.

[Reet]

Anyway, user.config system of .NET is quite flexible and automatic but complex too. Some settings could go bad if there are too many directories and config files for multiple revisions. I occasionally delete all directories except for the last version.

Yes, that's what I did effectively. Deleted all directories, tested normal operation, then put only directory for current version back. Perhaps VituixCAD could do some automatic cleanup, only retain config file for last version or something to that effect. I did have around 90 revisions in there

[kimmosto]

It says "Auto update, latest2.txt Version string portion was too short or too long."

Ok, it's the same error as before. New version tells filename to download: latest2.txt or VituixCAD2_setup.exe.
Basically programs just reads content of https://kimmosaunisto.net/Software/V...AD/latest2.txt
Program should be able to read it as easy as any web browser. Too short is e.g. 2 (less than two levels) and too long is 2.0.125.1.7 (more than four levels).

Anyway, user.config system of .NET is quite flexible and automatic but complex too. Some settings could go bad if there are too many directories and config files for multiple revisions. I occasionally delete all directories except for the last version.

[Reet]

Hmm, very odd the screenshot isn't showing. Let me try again:

It says "Auto update, latest2.txt Version string portion was too short or too long."

I'm not sure what the problem was, but I'm not getting the error anymore so we can forget about it for now. I have changed main directory, but nothing has changed there for a few years, folders are writable, have free space, etc.

I saved the config file before removing it from AppData folder if you'd like to review. It is attached, renamed to .txt to get around forum limitations.

Thanks for taking the time to look into it.

[kimmosto]

I have a different message:

Image with message is not visible here, but I guess download directory could be the problem because it's the only one related to user.config. Default download directory is "My Documents/VituixCAD/Download" but Main directory -setting in Options overrides that. For example my Main directory is "C:\Users\Kimmo\OneDrive\Documents\VituixCAD" so download directory is "C:\Users\Kimmo\OneDrive\Documents\VituixCAD\Downl oad". Download could fail if user.config is bad or download directory does not exist i.e. creation of directory fails or you don't have adequate access rights to it.
Next revision will try to create download directory right before download (not in program start-up), but that does not guarantee success if Main directory -setting in user.config is bad.

[Reet]

Manually downloaded the latest, I have a different message:


It may be a problem on my end, I deleted the config files from AppData/Local/Kimmo_Saunisto/*, it appears to have resolved it. Very confusing, I put the old config file back in place and the error has not returned. Who knows, but it's good now.

[kimmosto]

2.0.125.1 (2025-05-31)

Main

• Auto update is using HttpClient instead of (obsolete) WebClient.

Enclosure

• Online database is downloaded for browsing and database update using HttpClient instead of (obsolete) WebClient.

Merger

• Raw LF response traces try to maintain line width, color and style set in Traces window while current session.

Replacing WebClient with HttpClient class may not have any effect, but it should be more modern. This version should be downloaded and installed manually if previous versions and server do not co-operate anymore due to newer PHP version 8.2 at the server. Co-operation is tested automatically by Auto update in every start-up, or can be tested manually by browsing Online driver database in Enclosure tool.

[kimmosto]

^Works here but it does not prove anything because service provider is changing PHP support. Earlier PHP setting was 7.4 or some other old which will be removed from the server on Tue 2025-06-03. My new selection has been 8.2.28 for few days, but I just changed to "8.2.21 by OS vendor". It should be running already, but won't probably help due to same major version.



I'm not sure is this the problem and why, but this is the only thing which has changed since the previous revision.

Microsoft says that WebClient class VCAD is using for download is obsolete and should be updated to HttpClient. That probably enables downloading without PHP support so I'll make some tests and changes to auto update in few weeks.

[Reet]

Error with auto-update. I'm on version 2.0.124.1

[kimmosto]

2.0.125.0 (2025-05-30)

Main

• Calculation of front wall reflection in Room tab fixed with Distances > 90 m.

Enclosure

• Added Shelv HP to Filter tab.

Merger

• Phase responses shown on start-up.

[Reet]

Minor bug observed in the merger tool, "show phase" is checked by default when you open the tool, however phase is not shown until the box is un-checked and re-checked.

[witwald]

No, I haven't tried using an L-T with the B&C 18SW115 driver. The example L-T that has been provided above seems to essentially be a PEQ of +4dB at 40Hz with a low Q value, albeit with a fraction more boost at 10Hz than a simple PEQ would be expected to provide.

[kimmosto]

^I guess you haven't tested L-T for your B&C 18SW115 case? That includes shelf and two PEQs though the shelf is still LP. 'Hole in one' in theory, but more difficult to iterate manually.

[witwald]

The UI panel as shown, with the Shelv HP control added, would be excellent for my purposes. 🙂 I anticipate using it regularly when suggesting possible subwoofer designs in answer to queries about this driver or that driver. I'll be able to achieve a flatter response in the typical subwoofer passband, while at the same time allowing clear communication of the ensuing power requirements.

[kimmosto]

I do not understand the hesitation and the negative viewpoint.

Available space (in pixels) has always been a problem with Enclosure tool and main program assuming that program should support height of 768px. Without changing UI of active filters to some kind of list or scrollable panel, there is room for just one more equalizer (by overlapping default margins few pixels per control).

List UI would be less visual and slower and more difficult to use. Scrollable panel may hide something when display or window is small. Will this be enough - the last to be added and the most important for us, or is it just redundancy because single user is not willing to use shelving LP and scale with supply voltage? How much free time should I use for this, and how to prevent VituixCAD to be another REW with hundreds of complex features without actual significance.

[witwald]

For example this driver:

Thank you. I follow your drift now.

In (too) many cases simulation with T/S and reality don't have much common.

I understand that, and I take your point. However, the countering point is that, in many cases, the simulation using T/S parameters allows a quick and easy exploration of the available design space. Ideas can be fleshed out and tried to establish their workabilty and usefulness, and then quickly and easily shared with others who have an interest in such solutions.

Why simulation should be boosted with features which don't help to represent reality.

Ostensibly, this is really being much too harsh...I would equally argue that the features I have identified would be useful in representing reality, in much the same way the existing features help. I do not understand the hesitation and the negative viewpoint.

Of course VituixCAD has possibility to include traced or downloaded acoustical measurement of the driver, but combining of simulation and datasheet response and baffle step response and XO filter is NOT done in Enclosure tool.

Agreed. But the request is to be able to perform a simpler, idealised analysis...

So Enclosure tool does not really need more EQ features than for testing SPL/excursion capacity and co-operation of impedance curve and typical passive network.

I beg to differ, as the features I have requested would help greatly, without adding any extra complexity.

[kimmosto]

I don't follow what you are trying to say here. Can you please elaborate a little?

For example this driver:



In (too) many cases simulation with T/S and reality don't have much common. Why simulation should be boosted with features which don't help to represent reality. Of course VituixCAD has possibility to include traced or downloaded acoustical measurement of the driver, but combining of simulation and datasheet response and baffle step response and XO filter is NOT done in Enclosure tool. So Enclosure tool does not really need more EQ features than for testing SPL/excursion capacity and co-operation of impedance curve and typical passive network. The second one can be done with the main program too, but passive components in Filter tab enable faster testing and iteration.

[witwald]

Simple system simulator does not know for example how cone equalizes acoustical response...

I don't follow what you are trying to say here. Can you please elaborate a little?

[witwald]

Shelving HP and LP have the same response. Just gain is different which can be compensated with input voltage.

I understand that. However, it's non-intuitive in terms of viewing the filter response, and one needs to do an extra step and mentally subtract off the low-pass boost. Why not just add another option to help the user? It's much simpler at the software end of the tree. It is a simple additional capability that will reap major dividends for my simple exploratory work, enabling me to do simple things much more simply. Is that too much to ask? It would be nice to have an already powerful computational tool made even better.

[kimmosto]

Shelving HP and LP have the same response. Just gain is different which can be compensated with input voltage.
More important is to remember that Filter tab in Enclosure tool is NOT for designing actual/final crossover so it can be quite simple. It's just for investigating:
1) SPL and voltage limits with different bass boosts by active filter such as L-T, shelving LP or peaking EQ.
2) response reaction between driver's impedance response and passive filter. Especially how typical but annoying response hump at upper bass can be eliminated or impedance response equalized more flat or low pass designed for driver with quite high Le.
3) possibilities to extend response and add some protective high pass with series capacitor.

Speakers can be and have been designed for decades without any filter features in driver+box simulator. Simple system simulator does not know for example how cone equalizes acoustical response so it's not productive to put too much effort without actual measurable devices.

[witwald]

That is very true 👍, and it's something that I did to test feasibility and usefulness of my little idea. However, it would be extremely time saving in nature if the options that I suggested were available in the Enclosure tool. Sometimes one just wants to have a very short "feasibility study" without littering one's computer with a myriad of files. 🙂

[Reet]

For complex filtering you can always export the frequency response from the enclosure model, and load it to the main window to use any filter functions available.

[witwald]

For your consideration, please find below the details of some feature requests for VituixCAD's Enclosure simulation tool.

I have been working on modelling a B&C Speakers 18SW115-8Ω 18-inch driver in a large 160-litre vented enclosure tuned to 28Hz. This tuning produces a bass shelf in the low-frequency reponse, as shown by the black curve in the plot below.

I would like to be able to introduce a shelving filter to remove the rising response above 40Hz or so (the region highlighted in blue). This would need to be applied with negative gain.

Would you be able to add a 'Shelv HP' filter option to the Filter section of the Enclosure tool? I'd expect that it wouldn't be very difficult to do, as you already have the framework in place from the existing 'Shelv LP' filter option.

At the same time, would it also be possible to add another two PEQ filters? That way a total of 4 would be available in the Enclosure tool (i.e., PEQ 1, PEQ 2, PEQ 3, and PEQ 4).



Thank you very much for considering my requests.

[kimmosto]

2.0.124.1 (2025-05-11)

Enclosure

• Added 'Show current' command to context menu of Power chart.
• Added 'Show force' command to context menu of Excursion chart.
• 'Show current/voltage' and 'Show force/acceleration' track visibility set in Traces window.

User manual says now:

• Input Power: apparent power [VA], real power [W] and maximum power to Re [W].
  Current [A] when 'Show current' is checked in context menu, or
  Voltage [V] when 'Show voltage' is checked in context menu. Voltage trace includes Source voltage U and active filters, but not passive components.
• Peak excursion and Xmax [mm] of cone and passive radiator.
  Peak reaction force [N] of cones and passive radiators due to acceleration of moving mass when 'Show force' is checked in context menu, or
  RMS acceleration [m/s²] of cone and passive radiator when 'Show acceleration' is checked in context menu.

[kimmosto]

I switch off the display of 'Cone Force (peak)' in the 'Excursion' plot. However, when I change the power input level, the 'Cone Force (peak)' trace reappears. It seems that my prior setting is being somehow overwritten.

Visible trace (Force or Acceleration) should be selected via context menu (right click). Not via Traces window. The same story with Current/Voltage selection in Power chart. One or another is visible after the next calculation so hiding both is just temporary. Online manual says:



Next revision may have own switch for both traces in context menu. That would allow hiding both, but both can't be visible at the same time because they have different unit.

[witwald]

I am using VituixCAD 2.0.124.0, and would like to report a minor issue that I am experiencing.

When using the Enclosure tool, using the 'Excursion traces' dialog, I switch off the display of 'Cone Force (peak)' in the 'Excursion' plot. However, when I change the power input level, the 'Cone Force (peak)' trace reappears. It seems that my prior setting is being somehow overwritten.

This wasn't happening in the previous version of VituixCAD.

[kimmosto]

2.0.124.0 (2025-05-07)

Enclosure

• Added passive parallel filter branch Cp+Lp+Rp to Filter tab.
• Added 'Track Fb and Qtc' checkbox for Linkwitz-Transform. Copies Fb and Qtc of closed or IB to fo and Qo to help setting up L-T.
• Added optional voltage trace to Power chart. 'Show voltage' command in context menu replaces current trace with voltage.
• T/S parameters of the newly added driver are read from driver table into system simulation also when database filtering hides the other drivers.

[kimmosto]

2.0.123.2 (2025-04-05)

Main

• Klippel NFS CEA2034 directivity export files 'SPL Horizontal.txt' and 'SPL Vertical.txt' are renamed automatically to 'SPL Horizontal.nfs' and 'SPL Vertical.nfs' when loaded to Frequency responses -list in Drivers tab to avoid manual renaming.
  In addition, 'Angle parsing from filename' and 'Power response & DI calculation' settings in Options are adapted for NFS exports.

Enclosure

• Added reading of Shelv LP filter's Q factor from enclosure project file.

---

2.0.123.1 (2025-03-23)

Enclosure

• Maximum VAS, Sd and Mms increased by 10x.

[kimmosto]

2.0.123.0 (2025-03-11)

Impulse response

• Added 'FR view' tab for comparing selected source response to frequency response created with impulse response to be exported.
• Added horizontal scrollbar for adjusting Pre-delay. Tooltip shows delay in tap number and % of taps.
• 'Center IR' checkbox deleted.
• Fixed IR scaling with Pre-delay of 0.0 ms.

https://kimmosaunisto.net/Software/V...pulse_response
Refresh to see the latest.

[ergo]

I believe that Kimmo's Epe-3W_demo data is collected from a real small speaker box. Thus it does have "baffle step" effect included. Also Kimmo probably set the rotation axis to a tweeter acoustic center and woofer in most cases being a bit further would have a slight effect on SPL due to that.

Vifa datasheet on other hand would show a response when speaker is mounted on a big IEC standard baffle and they move the microphone instead. This lack baffle step effect.

For my own designs I've considered that at any given angle - ie 0deg / 30deg / 45deg etc, it is important that the relative levels between tweeter and woofer are correct. They will be imho very much good enough if you measure them rotating around tweeter axis. It will show you issues with power response and directivity mismatch etc if xover is not optimal.

So onto building - measuring and listening

Good luck with the project.

[Reet]

The low frequency inconsistencies can be caused by SNR of the measurement, at some low frequency the measurement may be dominated by the noise floor. It can also be related to a DC offset in the impulse response, in recent versions VituixCAD has improved the DC offset compensation in its IR-FR tool considerably, reducing this possibility.

Viewing the data un-normalized makes it clearer to identify the problem.


However, you may also notice that once a bandpass filter is applied to the driver, the error in response <100Hz is not impacting to the design results.


You are correct, force to gradient is one method of correction, but more of a Band-Aid solution, of course it's best to have good clean measurements to begin with. For the driver being discussed here, I would suspect it has not been merged with a nearfield response.

[Mogens20]

Hey Guys, I'm continuing to learn how to use this amazing software. After reading all the docs I can find more than once and completing a few speaker designs, I've noticed something unexpected to me.

I'll use the Epe-3W_demo_V2.vxp reference design for simplicity and since we all have access to the data. Below is the horizontal directivity of the Vifa M10MD from the Vituix file. I muted the woofer and tweeter.

I believe the <100Hz trace data deformity has been addressed in the current revision of VituixCad2 thanks to the Force To Gradient function. Or the left side IR window was too small?

This post is about the apparent directivity of the midrange between approximately 200-600Hz. Of course this can , and in this case seems to be, caused by the acoustic center of the driver not aligned with the axis of rotation. But I see this in other designs including my own and I've very careful to do my best to ensure the DUT alignment is as close as possible. This is also visible in the directivity graphs of the other drivers in this design.




Below is the manufacturer's half space frequency response for the Vifa M10MD. While the off-axis is only to 60Deg, the driver appears to be behaving like a point source in this graph up to around 600Hz.



If the DUT is properly aligned and manufacturer (or other half space) driver measurements indicate point-source-like dispersion up to a certain frequency, is it correct to expect very little low frequency directivity graph divergence in Vituix?

If DUT is misaligned with axis of rotation, should I mitigate this by shifting SPL traces (in REW for example) such that they align at the lowest displayed frequency? Should I also adjust the IR alignment accordingly?

[kimmosto]

2.0.121.1 (2024-12-27)

Main

• Modified constraints of slope target zones in CTA-2034 chart.

Preference rating

• On-axis linearity calculated as difference to linear regression line to support others than conventional full space concept.

Slope target limits as C# code for spinorama.org and reviewers in case they decide to show the same targets:

[Reet]

That's a a nice feature, I think many new users to power & DI charts will find that helpful. I am also happy to see that my own designs are falling within the recommended slope zones well enough for my liking.

[kimmosto]

2.0.121.0 (2024-12-22)

Main

• Added 'Show Slope target zones' command to context menu of CTA-2034 chart.
  Shows recommended slope target range for ON-LW, PIR, SP and SPDI @100-16000 Hz.

Enclosure

• Fixed reading of missing minimum limits in database filter.
  Maximum was moved to minimum if minimum cell was empty.

Slope target zones depend on slope of simulated/actual directivity index with some constraints. Few examples about adaptation and constraints.

[tktran]

I like it!

[kimmosto]

2.0.120.1 (2024-12-06)

Main

• Added 'Normalized' command to context menu of CTA-2034 chart.
  Shows flat frequency response to reference angle.
• Chart areas are aligned left and right.

[kimmosto]

2.0.120.0 (2024-11-23)

Main

• Added 'Show Data labels' command to context menu of CTA-2034 chart.
  Shows smoothness (SM) and slope in dB/oct of ON, LW, ER, PIR, SP, SPDI and ERDI @100-16000 Hz.

Main, Enclosure, Calculate T/S

• Scale of impedance phase axis changed to +120...-120 deg.

Power dissipation

• Added 'Traces...' command to context menu of chart.
• Added 'Save as overlay' command to context menu of chart.
• Added 'Open overlay...' command to context menu of chart. Drag&Drop overlay file is also supported.

Data labels of CTA-2034 chart

[JonMarsh]

Very excellent for me!

[kimmosto]

Tiny adjustments in the latest build 2.0.119.3 are related to the latest revision of this document: https://kimmosaunisto.net/Misc/speak...w_feedback.pdf
Refresh to see the latest 2024-11-17.

[kimmosto]

2.0.119.2 (2024-11-14)

• Size of texts changes when size of graph changes. This enables HD/2K, 4K and 8K bitmap copies, screenshots and exports directly without SVG files.

[kimmosto]

2.0.119.1 (2024-11-12)

Main

• Name of On-axis response in SPL and CTA-2034 charts is 'On-axis' when Ref angle=0 deg hor. Otherwise the name is 'Ref axis X deg hor'.
• Early Reflect Hor traces renamed to Horizontal Reflections and Early Reflect Ver traces renamed to Vertical Reflections.
• Added 'Show Reflection totals' command to context menu of CTA-2034 chart.
  Shows Vertical Reflections, Vertical Reflections DI, Horizontal Reflections and Horizontal Reflections DI. Hides nothing.

Optimizer

• On-axis text in radio buttons renamed to Ref axis.

Merger

• Axial column in HF list renamed to On-axis.

[Reet]

Reference axis or Reference angle is a good and generic term. Somewhat related, in the merger tool, the high frequency portion has the angle column labelled as "axial", perhaps this should change to "angle" to be consistent with the calculator tool