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6 September 2022 at 6:43 am #552Thanks for the screenshots. That’s exactly as expected and it’s caused by the linear phase LF rolloff in the filtered loudspeaker response. The only way to have a step response that steps up and stays up is to have a loudspeaker that has a flat response to DC.
To investigate the effect more, load FIR Designer without any loudspeaker measurement on the Import tab, then put a HPF filter either on the IIR filters tab or the Mag Adjust tab. If using the Mag Adjust tab, try minimum and linear phase and watch the effect on the step response.
Best regards,
EA Support
5 September 2022 at 7:29 am #546Put your images on a file sharing tool like Dropbox or an image hosting website, then put the link in a post here using the “IMG” option. (A web search should show a few sites.) If you use Dropbox, copy the share link then change the URL ending to have raw=1. For example
https://www.dropbox.com/s/tg0cfa565aue4ak/zoo.jpg?raw=1
Best,
EA Support
4 September 2022 at 7:20 am #544>> there does not seem to be a way to copy and paste the filter prototypes used to design a
>> target curve from the Mag sub-tab of the Target tab in workflow mode, to the Magnitude
>> Design tab of the Direct Design modeThat’s correct. The more common use case is the other way around; that is, design a target in direct design mode, save as a FDT file and import this on the main workflow Target tab.
>> It would be nice if we can have the FIR Designer target file export in addition to the
>> Export SMAART target file feature or an ability to copy filter prototypes between the two modes/tabs.Note.
Best regards,
EA Support
1 September 2022 at 7:46 pm #541Hi Thomas,
Long ramps in the filtered loudspeaker’s step response are usually from the LF rolloff. (Linearising the phase at very low frequencies requires a very long FIR filter.) Maybe post some screenshots of the step response and the filtered speaker’s mag/phase response.
Best regards,
EA Support
22 August 2022 at 5:41 pm #539>> Biamp Tesira FIR Block doesn’t allow values +/- 1,
>> Is there a way to remove them during export?On the FIR Designer export tab, there’s an “Output Gain (dB)” parameter. Use this to reduce the bulk level of the FIR filter by entering a negative dB value until the +/-1 warning goes away, then export.
Then elsewhere in the Biamp Tesira system, add a gain block to boost to recover the lost level (if you need to).
Best regards,
EA Support
10 August 2022 at 4:21 pm #533Thanks very much for posting this.
We do plan to save the captured SMAART traces but we don’t have any ETA on when this will be ready.
Best,
EA Support-
This reply was modified 3 years, 7 months ago by EA Support.
7 August 2022 at 9:39 pm #531Thanks. Just restart FIR Designer and it should trigger the link to 3.4.0 now.
Best,
EA Support
5 August 2022 at 7:47 am #528Hi Bob,
We don’t have a reference. Here’s something (we posted on ProSoundWeb back in January) which may help.
Re the actual averaging modes
- Complex: This is full transfer function averaging. The phase of the cabinet is retained.
- Power (flat, zero phase): This power averages the magnitude only and discards the phase.
- Power (minimum phase): This power averages the magnitude only and discards the phase, then calculates the minimum phase response from the magnitude response. For a single driver in an anechoic chamber, the resulting phase should be very similar to the full Complex average. For a multi-way system with crossovers, this mode gives the cabinet phase response minus the additional or “excess” phase from crossovers.
- Power (complex phase): This power averages the magnitude only then combines this mag with the phase from the Complex averaging mode.
- Power (min. phase + Ref. excess phase): This is the same as the “Power (minimum phase)” mode but the excess phase from the Reference measurement is added in. (The Reference excess phase is the original phase minus the phase from a minimum-phase calculation from the Reference magnitude.) In a nutshell it’s calculating the excess or crossover related phase from the Reference measurement, then adding this crossover phase to a minimum-phase average of all the measurements.
- Power (with complex avg. excess phase): The magnitude is a power average and the phase is the excess phase only. This could be useful for isolating excess or crossover related phase and only correcting this phase. We’re not aware of anyone using this but it was easy to calculate so we thought it worth including.
Best regards,
EA Support
5 August 2022 at 7:39 am #527Hi Bob,
The session file contains paths and filenames for all the measurement files used in the session. Usually this error message means the measurement files have been moved to a different folder/directory or deleted, and thus can’t be found. If that isn’t the case for you, send your .fda file to info at eclipseaudio dot com and we’ll take a look. Are you on windows or mac? Are the files on the same drive, a different drive or a network share?
Best regards,
EA Support
14 July 2022 at 6:13 pm #518Hi Eddie,
>> Doesn’t the latency increase if I create only the Magnitude
No. On the Auto Mag tab you have selected a minimum phase filter response. This puts the FIR filter peak at time=0, which you can see on the Export tab and provides essentially no latency. Can I suggest you research FIR filter basics? We have a white-paper at
while you may find helpful. Also take a look at the tutorials on
>> I use 8 measuring microphones to average the response of the room.
The averaged measurement on the Import tab still looks too detailed to be useful. I’d suggest applying some smoothing, either on the Import tab or on the Auto Mag tab.
Best regards,
EA Support
14 July 2022 at 4:50 pm #516Hi,
I’ve taken a look at your FIR Designer project file. It generates a minimum-phase FIR filter so the approximate delay through the filter is 0ms and is why you’re seeing no roughly the same latency with the FIR on & off.
Also, it’s generating a FIR filtering using the Auto Mag process with no smoothing. This is generally not a good idea. Fine resolution filtering like this may make the measurement position sound better, but will sound a lot worse in all other locations. We recommend some measurement averaging and Auto Mag smoothing.
Best regards,
EA Support
4 July 2022 at 11:24 pm #510Like we suggested, ensure the measurement doesn’t have significant bulk delay. Then you can apply variable smoothing and transfer to FIR Designer as freq/mag/phase TXT with reasonable confidence.
Best,
EA Support
4 July 2022 at 10:41 am #507It looks like FIR Designer matches REW in mag and phase. The measurement clearly has very high phase slope and thus significant bulk delay. This bulk delay should be removed in the measurement process if phase is to be used in any subsequent filter design. FIR Designer does its best to create an IR from the freq/mag/phase TXT format but using freq/mag/phase looses information when the measurement has very high phase slope. Better to export the measurement IR directly and load this into FIR Designer.
BTW, from a display perspective, in Preferences you can uncheck “Show phase plot wrapping” to remove the vertical lines between when the phase wraps.
Best,
EA Support
2 July 2022 at 11:10 am #503Thanks. Our apologies. In our haste to get an update out for you the change made it into the mac build but not the Windows build.
2.4.7 is now available and we’ve confirmed that the commas are there.
Best regards,
EA Support -
This reply was modified 3 years, 7 months ago by
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