Questions (and more)

[To: Matti Koskinen <mjkoskin@sci.fi>]

The piano.ins problem can be fixed, I think, by making
the first "start" argument a non-keyword argument.  I
put a note in the file about this awhile ago, but
I'll go ahead and change the instrument.

There's an example of time-varying filtering in addflt.ins,
and noi-attempt in ugex.ins, and comb-filters in zd.ins.

flt-a is an array of coefficients, so if you know what
you're doing you can simply set its elements via
envelopes or whatever.  The function make-filter-coefficients,
and various others in fltdes.lisp may be helpful
in this regard.

The type to use in make-array is 'frmnt -- "formnt" is
the name of the associated generator -- there's an example
in clm.html under the name "cross-synthesis".