• Q to bandwidth table

    Tables for conversion from Q to B/W (bandwidth) for DSP bell-type EQ.

    Parametric (adjustable) band-type filters use a width parameter that may come as a Q (resonance) factor or as a bandwith, normally as a fraction of an octave. The tables below show equivalences from one type of representation to the other. There is no standard way to convert bandwidths to Q factors (for a start, how does one measure the -3 dB points to determine the bandwidth of a parametric bell type filter with a gain of less than 3 dB?) , but these tables may be useful nevertheless. To convert an arbitrary Q factor to bandwidth, or viceversa, you can use the BW calculator from Doctor ProAudio's calculators.


    B/W (oct.)
    Bandwidth
    Q Q B/W (oct.)
    Bandwidth
    0,02 72,13 0,50 2,54
    0,03 48,09 0,55 2,35
    0,04 36,07 0,60 2,19
    0,05 28,85 0,65 2,04
    0,06 24,04 0,70 2,00
    0,07 20,61 0,75 1,80
    0,08 18,03 0,80 1,70
    0,09 16,03 0,85 1,61
    0,10 14,42 0,90 1,53
    0,20 7,21 0,95 1,46
    0,30 4,80 1,00 1,39
    0,40 3,60 1,10 1,27
    0,50 2,87 1,20 1,17
    0,60 2,39 1,30 1,08
    0,70 2,04 1,40 1,01
    0,80 1,78 1,50 0,94
    0,90 1,58 1,60 0,89
    1,00 1,41 1,70 0,84
    1,20 1,17 1,80 0,79
    1,40 0,99 1,90 0,75
    1,60 0,86 2,00 0,71
    1,80 0,75 3,00 0,48
    1,90 0,71 4,00 0,36
    2,00 0,67 5,00 0,29
    2,20 0,60 6,00 0,24
    2,40 0,54 8,00 0,18
    2,60 0,49 10,00 0,14
    2,80 0,44 20,00 0,07
    3,00 0,40 30,00 0,05
    B/W Q Q B/W