Forum Replies Created
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23 March 2024 at 7:45 am #792Understood. Even just increasing the channel count of the app involves significant UI work which we don’t have time for right now, but we’ll note this as a potential update for the future.
Regards,
EA Support
13 March 2024 at 7:20 am #789We don’t have much experience tuning line arrays. I know some systems, that don’t have FIR capability, do perform HF adjustment (as you described) using IIR filters or minimum phase FIR filters (which are essentially equivalent). The brands I’m thinking of treat the line as roughly 3 zones – short throw (lower boxes), medium throw (mid boxes) and long throw (upper boxes).
With FIR you can do things somewhat differently. For example you can EQ the whole array as one using IIR (or minimum phase FIR) – this retains the line array behaviour, particularly at LF and MF – then use FIR for “linear-phase” filtering of upper MF and HF for different groups of cabinets – upper, mid or lower. My understanding is that L’Acoustics array optimisation takes this approach, and some other brands may also.
Linear-phase FIR filters are a subset of FIR filters and have the same effective delay across all frequencies. For more on linear-phase FIR filters, read
Best regards,
EA Support
8 March 2024 at 8:10 am #787I’ve contacted DFM asking for the IIR parameters. Please let me know which information you need in detail.
Thanks. See the section “Branded IIR Filter Emulation” on
Regarding the Multiway FIR I have some questions:
– We mainly use multi-way speakers with active processing (no passive crossovers). So, I want to know the differences (advantages and disadvantages) between making the X-OVER using IIR HPF and LPF and enventually All-Pass filter for Phase slope correction, and then use a FIR in the input to flattern the phase from around 400Hz and above – and using FIR on each way instead of IIR.If both approaches result in the same transfer function, and you have the processing flexibility available, then there is no advantage of one method over the other method. However, doing crossovers and phase unwrapping all in FIR usually requires longer FIR filters, than doing a mixed IIR+FIR approach, and the maximum available FIR filter lengths in your processor might not be long enough. So mixed IIR+FIR might be the most viable for you.
Also with FIR, even though the software can calculate very fine and high-Q correction filters, we suggest taking care not to correct specifically for one measurement at one level. To help, we provide measurement averaging – the last tab in the workflow. You can use this to spatially overage measurements (and/or average measurements from different levels) then use the averaged measurement in the FIR Designer workflow.
Best regards,
EA Support
15 February 2024 at 2:42 pm #781I’ll email you directly. BTW what version do you currently have? The ‘new version available’ should provide a link, but there were some issues with this link approximately a year back, due to macOS changes.
Regards,
EA Support
5 February 2024 at 6:15 am #777BTW What microphone is this calibration file for? Between 20 Hz and 20 kHz, the file has a range of approximately -17 dB to +10 dB, and with an approximately 15 dB jump just above 16 kHz. This seems way too much variation for a measurement microphone. I would expect something in the range of -3 to 3 dB, and with very minimal phase change.
Regards,
EA Support
5 February 2024 at 5:20 am #776Thank you very much. We’ll look further into this.
Regards,
EA Support
4 February 2024 at 11:59 am #773More on Analog Devices, the IIR tab of FIR Designer can export raw coefficients for all IIR filters to a summary txt file, and the raw coefficients can be entered in this block.
Best regards,
EA Support
4 February 2024 at 9:58 am #772Regarding the dropdown menus, we checked the latest builds and they are all opening for a single click on both macOS and MS Windows. (We did some work on this a few years back.) Can you provide more details on where you are having to click more than once to open a dropdown?
Regards,
EA Support
27 January 2024 at 7:51 am #768Thanks for letting us know. We see the problem in version 1.7.7. (1.7.6 and earlier are ok.) We’re working on this now.
Regards,
EA Support
18 January 2024 at 2:30 pm #765Our apologies. The help pages are no longer available from the app. (They weren’t being used by 99% of users and so we disabled them from the website but haven’t yet removed the selection from the app.)
To help understand the workflow:
– download the demo version and look at the preloaded system.
– on the tutorials page, take a look at the “FIR Designer 3.0 ..” and “FIR Designer M ..” videos.Then if you have further questions, post them here on this forum.
Best regards,
EA Support
27 December 2023 at 7:31 am #758Hi LangCheng,
Regarding (1), I don’t have any recommendations here. The measurement location is for the user to decide, to suite their application.
Regarding (2), if you’re goal is only phase correction, I suggest using both the manual ‘Phase Adjust’ tab and the ‘Auto Phase’ tabs. For an example, watch the ‘FIR Designer 3.0 Complete Overview’ video.
Phase correction down to 300 Hz can require a fairly long filter. Ignore 256 taps @ 48 kHz and start with at least 512 taps. To better understand the effect of length, read our white-paper at the following link. (Specifically, see Section 5.)
Regarding (3), the ‘FIR Filter Delay’ relates to time=0 reference when designing the FIR filter. For most FIR filter designs, it corresponds to the peak location of the FIR filter coefficients. Since you are phase correcting, you will likely need to set the delay greater than 0. How much depends on your filter design.
Again, watch the ‘FIR Designer 3 Overview’ video and read the white-paper. (Specifically, see Section 7.)
Best regards,
EA Support
15 December 2023 at 7:17 am #756The “Save IIR Coefficients” function only saves the filters that are enabled, so my guess it that you only have one filter “On”.
Note that the save “FIR+Summary” on the export tab, export sub-tab does save all filters with a ENABLED or DISABLED annotation.
Best regards,
EA Support
13 December 2023 at 8:25 pm #750We already replied to your questions at
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