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High pass version of "rezzy" Orc/Sco

Date1998-11-14 05:34
FromHans Mikelson
SubjectHigh pass version of "rezzy" Orc/Sco
Hi,

Here is a high pass version of my low pass rezzy filter with a similar
structure.  I'll probably add this as a mode parameter to rezzy.

Bye,
Hans Mikelson

; ORCHESTRA
sr = 44100
kr = 4410
ksmps = 10
nchnls = 2

;---------------------------------------------------------------------------
------
; Saw with Mikelson Rezzy Filter
;---------------------------------------------------------------------------
------
        instr   15

idur    =       p3
iamp    =       p4
ifqc    =       cpspch(p5)*1.33
ifco    =       p6
ia2     =       1
krez    init    p7

kfco    expseg  100+.01*ifco, .2*idur, ifco+100, .5*idur, ifco*.1+100,
.3*idur, .001*ifco+100
kamp    linseg  0, .002, iamp, .2, iamp*.8, p3-.222, iamp*.5, .02, 0

; axn     moogvco ia2, ifqc, 1, 1
apulse  buzz    1,ifqc, sr/2/ifqc, 1 ; Avoid aliasing
asaw    biquad  apulse, 1, 0, 0, 1, -.999, 0 ; Biquad used as a leaky
integrator

; Set up for high pass version of rezzy.
kt      =       .75/sqrt(1+krez)
kc      =       sr/kfco/2/3.14159265
kq      =       krez/(1+sqrt(sqrt(1/kc)))
kb0     =       (kc/kq+kc*kc)*kt
kb1     =      (-kc/kq-2*kc*kc)*kt
kb2     =       kc*kc*kt
ka0     =       kc/kq+kc*kc
ka1     =      -kc/kq-2*kc*kc+1
ka2     =       kc*kc

ayn     biquad  asaw,  kb0, kb1, kb2, ka0, ka1, ka2  ; Biquad used for high
pass rezzy

        outs    ayn*kamp, ayn*kamp
        endin

; SCORE
f1 0 16384 10 1                               ; Sine

;    Sta  Dur  Amp    Pitch  Fco   Rez
i15  0.0  2    40000  7.05   1000  10
i15  +    .    40000  6.03   2000  20
i15  .    .    40000  6.10   4000  40
i15  .    .    40000  7.05   8000  80