Akso - Audio DSP Platform

filterMix

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1st order HP, BP and LP filters and unity-gain mixer (actually, this module only needs 2 6dB LP filters to do the job). 2 cutoff controls ability to morph the inputs over the different filters one by one at unity gain. 3 seperate resonance paths

Author: Remco van der Most

License: BSD

Github: sss/filter/filterMix.axo

Inlets

frac32buffer input

frac32buffer BP

frac32buffer LP

frac32.bipolar HiCut

frac32.bipolar LoCut

frac32.bipolar ResHP

frac32.bipolar ResBP

frac32.bipolar ResLP

frac32 Morph

Outlets

frac32buffer output

frac32 morph1

frac32 morph2

frac32 morph3

Parameters

frac32.u.map.freq HiCut

frac32.u.map.freq LoCut

frac32.s.map ResHP

frac32.s.map ResBP

frac32.s.map ResLP

frac32.u.map morph

Declaration

int32_t val1;
int32_t val2;
int32_t feedHP;
int32_t feedBP;
int32_t feedLP;
int32_t HP;
int32_t BP;
int32_t LP;
int32_t hp;
int32_t bp;
int32_t lp;
int32_t morph;
int32_t mrph1;
int32_t mrph2;
int32_t mrph3;
int32_t res1;
int32_t res2;
int32_t res3;

Init

val1 = 0;
val2 = 0;
int32_t HP = 0;
int32_t BP = 0;
int32_t LP = 0;

Control Rate

int32_t f;
MTOF(param_HiCut + inlet_HiCut, f);
int32_t g;
MTOF(param_LoCut + inlet_LoCut, g);
morph = (inlet_Morph + param_morph) & ((1 << 27) - 1);
mrph1 = ((1 << 27) - ((morph * 3))) > 0 ? (1 << 27) - ((morph * 3)) : 0;
mrph1 = ((morph * 3) - (1 << 27)) > 0 ? ((morph * 3) - (2 << 27)) : mrph1;
mrph1 = mrph1 > 0 ? mrph1 : 0;

morph = (inlet_Morph + param_morph + ((2 << 27) / 3)) & ((1 << 27) - 1);
mrph2 = ((1 << 27) - ((morph * 3))) > 0 ? (1 << 27) - ((morph * 3)) : 0;
mrph2 = ((morph * 3) - (1 << 27)) > 0 ? ((morph * 3) - (2 << 27)) : mrph2;
mrph2 = mrph2 > 0 ? mrph2 : 0;

morph = (inlet_Morph + param_morph + ((1 << 27) / 3)) & ((1 << 27) - 1);
mrph3 = ((1 << 27) - ((morph * 3))) > 0 ? (1 << 27) - ((morph * 3)) : 0;
mrph3 = ((morph * 3) - (1 << 27)) > 0 ? ((morph * 3) - (2 << 27)) : mrph3;
mrph3 = mrph3 > 0 ? mrph3 : 0;

outlet_morph1 = mrph1;
outlet_morph2 = mrph2;
outlet_morph3 = mrph3;
res1 = __SSAT(inlet_ResHP + param_ResHP, 27);
res2 = __SSAT(inlet_ResBP + param_ResBP, 27);
res3 = __SSAT(inlet_ResLP + param_ResLP, 27);

Audio Rate

hp = (inlet_HP);
bp = (inlet_BP);
lp = (inlet_LP);
HP = ___SMMUL(mrph1 << 3, hp << 1) + ___SMMUL(mrph3 << 3, bp << 1) +
     ___SMMUL(mrph2 << 3, lp << 1) + feedHP;
BP = ___SMMUL(mrph2 << 3, hp << 1) + ___SMMUL(mrph1 << 3, bp << 1) +
     ___SMMUL(mrph3 << 3, lp << 1) + feedBP;
LP = ___SMMUL(mrph3 << 3, hp << 1) + ___SMMUL(mrph2 << 3, bp << 1) +
     ___SMMUL(mrph1 << 3, lp << 1) + feedLP;

val1 = ___SMMLA(((-HP + BP) - val1) << 1, f, val1);
val2 = ___SMMLA(((-(val1 + HP) + LP) - val2) << 1, g, val2);
outlet_out = val2 + val1 + HP;
feedHP = ___SMMUL(outlet_out << 3, res1 << 2);
feedBP = ___SMMUL(outlet_out << 3, res2 << 2);
feedLP = ___SMMUL(outlet_out << 3, res3 << 2);