/sflib/x example "harmonizer2,"  like several other ECMC PVC examples,
is a  mix of two soundfiles, produced by example scripts
harmonizer2-1" and harmonizer2-2". To see the source files for
"harmonizer2-1" or "harmonizer2-2" type
   pvcex  harmonizer2-1 
   pvcex  harmonizer2-2

"harmonizer2-1" :
Input soundfile "vln.g3" is "harmonized" as a dyad with pitches
at b1 (g3 transposed down 20 semitones) and bf5 (g3 transposed up
27 semitones). The lower note is resynthesizewd using only frequencies
between g5 (9.07) and g7 (11.07) from the source soundfile. The high
note is resynthesized using only the first 4 harmonics (7.07 to 9.07). 
The amplitudes of the 2 notes are boosted, respectively, by 30 and 20 dB.

echo \
\
-20         9.07  11.07   30 \
27          7.07 9.07  20\
\
> $SFDIR/harmonizermap
#HARMONIZER_shift_file=harmonizermap

The source tone (g3) is suppressed in resynthesis:
SOURCE_gain_in_dB=-96 # -0  # int,float or FUNC

An amplitude envelope that increases and then decreases in intensity
linearly is applied to both harmonized notes:
gen3 -L100 -24 -8 -24 > $SFDIR/gainfunc
MASTER_gain_in_decibels=$SFDIR/gainfunc  # int,float or FUNC
-----
ECMC PVC example script "harmonizer2-2"  is identical to example
script "harmonizer2-1" except for the band of frequencies used
to resynthesize the two notes:
echo \
\
-20         10.07  -1 10 \
27          7.06 7.09  30 \
\
> $SFDIR/harmonizermap
Here, the low note (b1) is resynthesized using only frequencies
above g6 (the 8th harmonic) of the source violin tone, and the high
note (bf6) is resynthesized as a sine wave, using only the fundamental
of the source sound.

