Forum Replies Created
19 September 2021 at 9:01 am #354
We haven’t yet implemented the system step response but yes, it would be good to see. It’s on the TODO list. As an alternative, the “Wavelet Transform” view shows the combined system behaviour and gives a sense of the overall temporal response.
14 September 2021 at 9:25 am #351
- This reply was modified 5 days ago by EA Support.
Sounds good. The Help in FIR Designer M is quite lean and focusses mostly on UI controls and their effects.
I’d suggest starting with the tutorials and videos on https://eclipseaudio.com/fir-filter-design-tutorial/
EA Support14 September 2021 at 8:09 am #348
FDW is REW’s equivalent of SMAART’s FTW and SysTune’s TFC.
Whether or not to use it is completely up to you, and is based on your measurement environment and preferred workflow.
FDW, FTW and TFC are intended for situations where there might be strong mid and/or high frequency room reflections (which we’d like to remove from the TF with a window) and where shortening a traditional window (to remove these reflections) would cause loss of resolution in the LF. The frequency varying window provides for a longer window length at LF and shorter window length at HF. In a lab environment or anechoic chamber where reflections are minimal, FDW, FTW and TFC aren’t really necessary.
We have customers who use the SMAART FTW by default for measurements that they use in FIR Designer, and it gives them tuning results they are happy with.
https://www.rationalacoustics.com/download/Smaart-v8.3-Release-Overview.pdf See page 8.
https://www.prosoundtraining.com/2010/03/15/easera-systune/ See Figure 1.
13 September 2021 at 1:33 pm #346
- This reply was modified 1 week, 3 days ago by EA Support.
I presume you’re referring to windowing like SMAART’s FTW or SysTune’s TFC? No we don’t provide anything like these at measurement import. FTW and TFC are assisted by time averaging during the measurement process. By the time a “measurement” gets to FIR Designer, we don’t have DUT and reference signals from which to calculate frequency varying windowed TF’s and then a time averaged TF. In theory we could implement a frequency varying window process at measurement import, however for non-lab situations (like measurements in auditoriums), it’s unclear how effective this would be, when compared to the SMAART or SysTune methods of performing this along with time averaging.
We do provide fractional octave based frequency smoothing at measurement import. And in the “Auto Mag” and “Auto Phase” FIR tabs, there is the ability to use different fractional octave frequency smoothing in different frequency regions.
EA Support30 March 2021 at 8:58 pm #329
We’re very sorry to hear this. We need some more information to replicate the problem.
What version are you using?
What sample rates do you have set for the channels?
Are you on any particular tab (in the workflow) when the crash occurs?
What other windows are open? (e.g. second view, aux responses)
If you have any work already saved to system and (channel) project files, please email them all to firstname.lastname@example.org.
EA Support21 February 2021 at 8:53 pm #320
Is this an electrical/digital measurement of the filter in a processor? Or an acoustic measurement of the filter applied to a loudspeaker?
The amount of pre-ringing in the filter depends on how filter filter is designed and what your goals are (e.g. phase linearisation).
Reply to this post then email the FIR Creator project and/or filter to our support address and we’ll take a look.
EA Support6 February 2021 at 7:16 am #317
We suspect the LIR is a complementary crossover where one channel is IIR filtered (e.g. HPF) and the other channel (with a LPF response) is created from the difference between the original input (with some small delay) and the filtered signal. When the two channels are added back together, only bulk delay is present and there isn’t any frequency varying phase shift.
We’ve been asked previously about implementing complementary crossovers in FIR Designer M and it’s on the todo list. To match LR’s LIR, we need to check with LR as to exactly what IIR filters they are using. Their paper suggests a 4th order IIR (for the HPF) and in our limited experience with this method, it results in approximately a 2nd order response on the complementary channel.
EA Support11 December 2020 at 7:12 am #307
It’s all there in the table on https://eclipseaudio.com/
Specific to making a FIR filter, the key difference is that FIR Designer doesn’t have any limits on the number of prototype Mag and Phase filters you can use and on the number of frequency bands or regions in the Auto Mag and Auto Phase tabs.
Also, FIR Designer has integrated measurement averaging and a few workflow helpers like Second View, Impedance viewing and no limits on the number of simultaneous project windows visible at any one time.
Maybe take a look at the FIR Designer 3 Overview video on
EA Support7 December 2020 at 11:29 pm #305
If IIR data from REW is exported as “filter settings,” then we (EA) need to either get the exact math from REW or take the time to match REW to known equations for IIR filters.
If IIR data from REW is exported as “filter coefficients,” then we could add the capability to load in the raw coefficients, but those IIR filters would not be editable or adjustable in FIR Designer. And the user would need to ensure the sample rates between REW and FIR Designer matched.