Shepard tone - v1.0 This instrument creates a Shepard tone. See http://en.wikipedia.org/wiki/Shepard_tone for more info on what a Shepard tone is. p-fields: p4 is the pitch or frequency p5 is the amplitude BSB widgets: speed is how fast each component varies envelope shape determines when the amplitude of a component is the highest, more to the beginning or to the end; use 0.5 for regular Shepard tone pulse width is used for the vco2 opcode if the waveform is square or triangle, values are limited to the stable range speed, envelope shape, pulse width and panning have an extra text field which in the code is appended to the value of the knob; use e.g. *p6 to change the value from the score For a regular Shepard tone, use a sine wave. The other waveforms have strange artefacts, which can be nice. gi_sine ftgen 0, 0, 65536, 10, 1 ifreq getFrequency p4 iamp = ampdb(p5) kenv adsr <attack>, <decay>, <sustain>, <release> asig mvpShepardComponent ifreq, <freq_dir>, <envelope_shape><env_shape_mod>, (<speed><speed_mod>)/<nr_tones>, 0, <nr_tones>, <wave>, <pw><pw_mod> asig = asig*kenv*iamp/<nr_tones> kleft, kright panner <pan><pan_mod> blueMixerOut asig*kleft, asig*kright nr_tones 126 70 true 2.0 20.0 1.0 6.0 150 true freq_dir 130 115 Up 1 Down -1 1 true 14 118 Frequency moves wave 23 263 Sine -1 Sawtooth 0 Triangle 4 Square 2 Paraboles 8 0 true pw 131 285 true 0.15 0.85 0.2209673 60 true speed 497 95 true 0.0 10.0 3.2168531 60 true 497 73 Speed (Hz) 13 77 Nr of components 25 229 <html>Waveform</html> 129 264 Pulse width 377 73 Envelope shape envelope_shape 391 95 true 0.0 1.0 0.5064934 60 true pan 647 95 true -1.0 1.0 0.005028963 60 false 654 73 Panning env_shape_mod 396 173 50 speed_mod 502 173 50 pan_mod 652 173 50 pw_mod 136 365 50 decay 427 273 true 0.0 1.0 0.21426898 50 false sustain 480 273 true 0.0 1.0 0.8715427 50 true release 533 273 true 0.0 10.0 1.6481674 50 false attack 374 273 true 0.0 10.0 0.19239195 50 false 378 254 Attack 431 254 Decay 481 254 Sustain 534 254 Release 377 224 <html>Amp Env</html> 15 8 <html>Shepard tone</html> mvpShepardComponent a kikkiiik kfreq, ifreq_dir, kenv, kspeed, icomp, inr_components, iwave, kpw xin kph phasor kspeed, icomp/inr_components ; kenv allows you to put more emphasis on the first or the last part, ; so the high frequencies or the low frequencies are emphasized kamp loopsegp kph, 0, kenv, 1, 1-kenv, 0 ; vary the frequency such that two consecutive components are one octave apart ; note that this is accomplished by the phase difference in kph k1 = (kph-0.5)*inr_components*log(2)*ifreq_dir kfreq1 = kfreq*exp(k1) if (iwave==-1) then asig oscili kamp, kfreq1, gi_sine else asig vco2 kamp, kfreq1, iwave, kpw endif ; this UDO is used recursively: if (icomp<(inr_components-1)) then asig_rec mvpShepardComponent kfreq, ifreq_dir, kenv, kspeed, icomp+1, inr_components, iwave, kpw asig = asig + asig_rec endif xout asig panner kk k ; sin/cos taper, constant power. kPanpos xin kPanpos = kPanpos/2 kPanpos = kPanpos * 3.14159265359 * .5 kLeft = sqrt(2) / 2 * (cos(kPanpos) - sin(kPanpos)) kRight = sqrt(2) / 2 * (cos(kPanpos) + sin(kPanpos)) xout kLeft,kRight getFrequency i i ipch xin iout = (ipch < 15 ? cpspch(ipch) : ipch) xout iout