Retain or reject specified bands. This is a spectral version of a graphic equalizer without the graphics. Controlled by datafiles, it can have any number of bands, but none of them are time-varying, i.e. there is no amplitude control. MODES 1. Single bandwidth specified by datafile greq1 2. Separate bandwidths specified by datafile greq2 OPTION • Reject Bands - check this option to create a bank of notch filters. (Unchecked: retain specified bands.) PARAMETERS greq1 Text datafile defining a single bandwidth in octaves, followed by a list of centre frequencies, one per band. Example: a number of narrow bands centred around
harmonics of A
110Hz.
greq2
Text
datafile of pairs of values, one per band,
of: centre
frequency and bandwidth 0.1
110 220 440
550
660
880
1100
Example: a number of bands centred around
odd-numbered harmonics of
Ab 100Hz; the higher bands have
progressively wider
bandwidth.
100
0.25
NOTES 300 0.50 500 0.75 700 1.00 900 1.25 1100 1.50 1300 1.75 1500 2.00 This program looks decidedly old-fashioned in an era of sophisticated graphic controls. However, the ability to define a detailed filterbank in a sinmple text file is also very powerful. Soundshaper's Graph Editor has two presets which can be employed to generate 1/3-8ve and 2/3-8ve sets of data for greq2.
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