AudioGuide version 1.74

New Writing for Instruments article and video tutorial.

Various improvements and bug fixes, mostly related to instrument writing.

• added a method instrParams={'pitched': False} for unpitched instrument csf()s that should bypass pitchfilters and interval restrictions. Useful for unpitched sound collections that shouldn't be subject to static or temporal pitch filtering.

• added a method pitchfilter={'harmonics': ['D1']} for filtering with harmonics of one or more fundamental frequencies. This may be combined with other parameters; e.g. pitchfilter={'harmonics': ['D1'], 'pitches'=['C3', 1]} gives all harmonics of D1 as well as C3 and C# in any octave.

• rewrote instr(interval_limit_range_per_sec) so that it works properly.

• bug fixes for pitchfilter, 'closest' sub method of spass('parser'), midiPitchMethod={'type': 'file_match'}