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Pch Add Processor

Pch Add

Parameters: pfield, value

The PchAddProcessor works like the AddProcessor, but is used with pfields written in Csound pch notation(i.e. 8.00, 7.11, 9.03). The value field, unlike the AddProcessor, is a whole-number, representing the number of scale degrees in which to add to the pch value. If a soundObject has notes where p5 is a pch value, and you the notes have values of 8.00, 8.04, 8.07, and 9.00:

i1 0 2 8.00
i1 + . 8.04
i1 + . 8.07
i1 + . 9.00

If a PchAddProcessor with value 7 and pfield 5 is used, after processing, the score would result in:

i1  0.0 0.5 8.07
i1  0.5 0.5 8.11
i1  1.0 0.5 9.02
i1  1.5 0.5 9.07

(The p2 and p3 times above are post-processing for a 2 second duration soundObject with time behavior set to scale.)

If you had used a regular AddProcessor and tried to transpose 7 scale degrees down using -.07, you would have gotten 7.93, 7.97, 8.00, and 8.97, and the first few notes would have really be equal to 14.11, 15.01, and 8.00 in pch notation. This is due to the way that Csound pch notation works to hold the scale degree, from 0-11, in the two fields to the right of the period.