Gabriel, I think it depends on what you are trying to do. What’s your context?
For example a Vocoder (for voice) might have a different distribution of bands (bark scale) than a multipurpose graphic EQ (even octaves). One strange example I know of is the Serge resonant EQ (not crossovers but fixed frequency resonant peaks) has deliberately picked frequencies that, “except for the top and bottom frequency bands, the bands are spaced at an interval of a major seventh. The Resonant Equalizer is designed to produce formant peaks and valleys similar to those in acoustic instruments.” Matt > On 23. Mar 2018, at 13:05, robert bristow-johnson <r...@audioimagination.com> > wrote: > > On 3/23/18 12:01 AM, gm wrote: >> What are good frequencies for band splits? (2-5 bands) >> >> What I am doing is divide the range between 100 Hz 5-10 kHz >> into equal bands on a log scale (log2 or pitch). >> >> Are there better strategies? >> Or better min/max frequencies? >> How is it usually done? > > conventionally, a graphic EQ might be split into bands with log center > frequencies every octave, for a 10 band, or every 1/3 octave for a 31 band EQ. > > i think the 10-octave frequencies might be at > > 25, 50, 100, 200, 400, 800, 1600, 3200, 6400, 12800 Hz > > with the bandedges at the geometric mean of adjacent pair of frequencies > > but they might put them conventionally at > > 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000, 20000 Hz > > you can see there's a bigger-than-octave gap between 200 and 500. > > maybe the 31-band 1/3 octave frequencies might conventionally be at > > 20, 25, 32, 40, 50, 63, 80, 100, 125, 160, 200, 250, 320, 400, 500, 630, 800, > 1000, 1250, 1600, 2000, 2500, 3200, 4000, 5000, 6300, 8000, 10000, 12500, > 16000, 20000 Hz > > those are conventional frequencies. not all spacing are exactly 1/3 octave. > you can see that 630 is a compromise between twice 320 and half of 1250. you > might want your bands split precisely in 1/3 octaves spaced apart by a > frequency ratio of 2^(1/3) which is about 1.26. that might have bands > labeled: > > 20, 25, 32, 40, 50, 63, 80, 100, 126, 159, 200, 252, 318, 400, 504, 635, 800, > 1007, 1271, 1600, 2014, 2542, 3200, 4028, 5084, 6400, 8056, 10168, 12800, > 16112, 20336 Hz > > > -- > > r b-j r...@audioimagination.com > > "Imagination is more important than knowledge." > > > > _______________________________________________ > dupswapdrop: music-dsp mailing list > music-dsp@music.columbia.edu > https://lists.columbia.edu/mailman/listinfo/music-dsp > _______________________________________________ dupswapdrop: music-dsp mailing list music-dsp@music.columbia.edu https://lists.columbia.edu/mailman/listinfo/music-dsp
