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#N canvas 343 48 578 498 12;
#N canvas 158 4 728 420 16x 0;
#X obj 21 151 *~ 0.064;
#X obj 21 174 rpole~ 0.93538;
#X obj 21 197 *~ 0.00431;
#X obj 21 220 cpole~ 0.96559 0.05592;
#X obj 21 246 cpole~ 0.96559 -0.05592;
#X obj 21 269 *~ 0.125;
#X obj 21 292 rzero~ -1;
#X obj 21 315 rzero~ -1;
#X obj 21 338 rzero~ -1;
#X obj 21 66 phasor~;
#X obj 204 29 block~ 1024 1 16;
#X obj 21 31 inlet;
#X obj 21 372 outlet~;
#X text 170 151 These objects make a 3-pole \, 3-zero Butterwirth low-pass
filter with cutoff at 15kHz (assuming 44100 sample rate.) The filter
was designed using the "buttercoef3" abstraction introduced in patch
H13.butterworth.pd in this series.;
#X connect 0 0 1 0;
#X connect 1 0 2 0;
#X connect 2 0 3 0;
#X connect 3 0 4 0;
#X connect 3 1 4 1;
#X connect 4 0 5 0;
#X connect 5 0 6 0;
#X connect 6 0 7 0;
#X connect 7 0 8 0;
#X connect 8 0 12 0;
#X connect 9 0 0 0;
#X connect 11 0 9 0;
#X restore 23 148 pd 16x;
#X floatatom 23 111 7 0 0 0 - - -;
#X obj 109 149 phasor~;
#X obj 22 194 output~;
#X obj 108 194 output~;
#X obj 23 83 mtof;
#X floatatom 23 59 3 -24 135 0 - - -;
#X text 131 18 UPSAMPLING TO CONTROL FOLDOVER;
#X text 56 57 <-- pitch;
#X text 126 250 not;
#X text 22 265 sampled;
#X text 26 249 16x up-;
#X text 20 293 The "pd 16x" subpatch at left contains a phasor~ object
\, but is locally upsampled by a factor of sixteen. Without upsampling
\, partials as low as 24 Khz. fold back over into the audible range.
With upsampling \, the first audibly folding over partial is at almost
700 Hz \, 29 times higher. The relevant partials will be 29 times \,
or almost 30 dB \, quieter when upsampled.;
#X text 21 403 A third-order Butterworth filter is used inside the
"pd 16x" subpatch - without that \, the internal signal would fold
over as it gets downsampled at the outlet~ object.;
#X text 324 464 Updated for Pd version 0.39;
#X connect 0 0 3 0;
#X connect 0 0 3 1;
#X connect 1 0 0 0;
#X connect 1 0 2 0;
#X connect 2 0 4 0;
#X connect 2 0 4 1;
#X connect 5 0 1 0;
#X connect 6 0 5 0;