Support Forums Forums FIR Designer Support How to export a FIR filter? Reply To: How to export a FIR filter?

    10 December 2023 at 8:15 pm #748

    I understand IIR(biquad) filter changes gain and phase
    all pass filter doesnt change amplutude, but phase changed.

    That’s correct.

    FIR(Finite impulse Response)filter, amplitude changes, but phase does not change.
    with higher tap, create long delay.

    That is not correct. A FIR filter can also change phase. (The FIR filter type you are describing is a “linear phase” filter which is subset of what FIR filters can do.) Take a look at the following guide; especially section 7.

    FIR Filter Guide

    I imported csv file into Symetrix, it looks like bunch of PEQ collection(IIR filter)

    If the FIR filter response looks like a collection of PEQ’s, that is probably because you have used some PEQ’s on the “FIR Magnitude Adjust” tab, to make the FIR filter. The responses of all five “FIR..” tabs are combined to make the FIR filter. Please take a look at the two tutorials I mentioned in my first message (above).

    Here is an example of a .._summary.txt file. It lists the filters from the “IIR Filters” tab, and basic information about the FIR filter file (which is saved separately).

    Filename: /Users/<username>/Downloads/FIRfilter__SUMMARY.txt
    Project: (none)
    FIR Designer 2 version: 4.0.1
    Sampling Rate: 48000 Hz
    Gain: 0.000 dB
    Flip Polarity / Invert: No
    GPD Tab Delay: 0 samples, 0.000 milliseconds
    IIR (Generic)
    b0:0.9907866979404248 b1:-1.9815733958808497 b2:0.9907866979404248
    a0:1.0000000000000000 a1:-1.9814885091445693 a2:0.9816582826171302
    BAND_PASS, 364.529 Hz, BW 2.000 (Q 0.667), -6.162 dB, ENABLED
    b0:0.9753337038790250 b1:-1.9007342759081824 b2:0.9275665093063239
    a0:1.0000000000000000 a1:-1.9007342759081824 a2:0.9029002131853491
    BAND_PASS, 3122.277 Hz, BW 0.863 (Q 1.647), -5.312 dB, ENABLED
    b0:0.9340057741878747 b1:-1.5705317765303994 b2:0.7774914181148489
    a0:1.0000000000000000 a1:-1.5705317765303994 a2:0.7114971923027236
    HIGH_SHELF, 8384.027 Hz, BW 1.900 (Q 0.707), 3.612 dB, ENABLED
    b0:1.2973957851235292 b1:-0.7856595921197735 b2:0.1733106061768412
    a0:1.0000000000000000 a1:-0.4018695414139699 a2:0.0869163405945669
    Sampling Rate: 48000 Hz
    Filename: /Users/<username>/Downloads/FIRfilter.fdt
    Length: 400 samples, 8.333 milliseconds
    Delay: 200 samples, 4.167 milliseconds