;Written by Iain McCurdy, 2006 -+rtaudio=PortAudio -b4096 sr = 44100 ;SAMPLE RATE kr = 44100 ;CONTROL RATE ksmps = 1 ;NUMBER OF AUDIO SAMPLES IN EACH CONTROL CYCLE (MAY NEED TO BE LOW WHEN WORKING WITH SHORT DELAY TIMES DEFINED INITIALLY AT KRATE) nchnls = 2 ;NUMBER OF CHANNELS (2=STEREO) ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "Flanger Implementation", 500, 350, 0, 0 ; ON | OFF | TYPE | WIDTH | HEIGHT | X | Y | OPCODE | INS | STARTTIM | DUR gkOnOff,ihOnOff FLbutton "On/Off", 1, -1, 2, 200, 30, 0, 0, 0, 1, 0, -1 ;VALUE_DISPLAY_BOXES WIDTH | HEIGHT | X | Y iddlt FLvalue " ", 100, 20, 0, 80 idmix FLvalue " ", 100, 20, 0, 130 idfeedbackamt FLvalue " ", 100, 20, 0, 180 idamp FLvalue " ", 100, 20, 0, 230 idFlaDepth FLvalue " ", 100, 20, 0, 280 idFlaRate FLvalue " ", 100, 20, 0, 330 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkdlt,ihdlt FLslider "Delay Time (sec)", .0001, 1, -1, 5, iddlt, 500, 30, 0, 50 gkmix,ihmix FLslider "Dry/Wet Mix", 0, 1, 0, 5, idmix, 500, 30, 0, 100 gkfeedamt,ihfeedamt FLslider "Feedback Amount", -.99, .99, 0, 5, idfeedbackamt, 500, 30, 0, 150 gkamp,ihamp FLslider "Output Amplitude Rescaling", 0, 1, 0, 5, idamp, 500, 30, 0, 200 gkFlaDepth,ihFlaDepth FLslider "Flanger Modulation Depth (sec)", 0, .2, 0, 5, idFlaDepth, 500, 30, 0, 250 gkFlaRate,ihFlaRate FLslider "Flanger Modulation Rate", .001, 7, -1, 5, idFlaRate, 500, 30, 0, 300 ;SET_INITIAL_VALUES VALUE | HANDLE FLsetVal_i .0001, ihdlt FLsetVal_i .5, ihmix FLsetVal_i -1, ihOnOff FLsetVal_i .9, ihfeedamt FLsetVal_i .7, ihamp FLsetVal_i .005, ihFlaDepth FLsetVal_i .05, ihFlaRate FLpanel_end ;END OF PANEL CONTENTS ;INSTRUCTIONS AND INFO PANEL FLpanel " ", 500, 280, 512, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " delayr delayw deltap3 - flanger ", 1, 5, 14, 490, 15, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 15, 5, 20 ih FLbox "A flanger is really just a delay effect where the delay tap ", 1, 5, 14, 490, 15, 5, 40 ih FLbox "is slowly modulated using an LFO (Low Frequency Oscillator). ", 1, 5, 14, 490, 15, 5, 60 ih FLbox "Typically the delay times involved in this system are very ", 1, 5, 14, 490, 15, 5, 80 ih FLbox "short so that rather than being able to hear distinct echoes,", 1, 5, 14, 490, 15, 5, 100 ih FLbox "the comb filtering effect of very short delays is evident. ", 1, 5, 14, 490, 15, 5, 120 ih FLbox "A feedback loop is essential to creating the sound of a ", 1, 5, 14, 490, 15, 5, 140 ih FLbox "flanger. ", 1, 5, 14, 490, 15, 5, 160 ih FLbox "A flanger derives its name from that fact that when ", 1, 5, 14, 490, 15, 5, 180 ih FLbox "originally implemented using reel-to-reel tape recorders the ", 1, 5, 14, 490, 15, 5, 200 ih FLbox "engineer was required to rub their finger against the flange ", 1, 5, 14, 490, 15, 5, 220 ih FLbox "of the reel of tape with varying pressure in order to create ", 1, 5, 14, 490, 15, 5, 240 ih FLbox "the short varying delay time modulations. ", 1, 5, 14, 490, 15, 5, 260 FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; instr 1 ;PLAYS FILE if gkOnOff!=-1 kgoto CONTINUE ;SENSE FLTK ON/OFF SWITCH turnoff ;TURN THIS INSTRUMENT OFF IMMEDIATELY CONTINUE: ;OUTPUTS OPCODE FILE | SPEED | INSKIP | LOOPING (0=OFF 1=ON) gasigL, gasigR diskin "808loop.wav", 1, 0, 1 endin instr 2 ;FLANGER-DELAY INSTRUMENT afeedbacksigL init 0 ;LEFT AND RIGHT CHANNELS OF THE FEEDBACK SIGNAL ARE INITIALISED TO ZERO afeedbacksigR init 0 ;LEFT AND RIGHT CHANNELS OF THE FEEDBACK SIGNAL ARE INITIALISED TO ZERO iporttime = .1 ;PORTAMENTO TIME kporttime linseg 0, .001, iporttime, 1, iporttime ;USE OF AN ENVELOPE VALUE THAT QUICKLY RAMPS UP FROM ZERON TO THE REQUIRED VALUE PREVENTS VARIABLES GLIDING TO THEIR REQUIRED VALUES EACH TIME THE INSTRUMENT IS STARTED kdlt portk gkdlt, kporttime ;PORTAMENTO IS APPLIED TO THE VARIABLE 'gkdlt'. A NEW VARIABLE 'kdlt' IS CREATED. adlt interp kdlt ;A NEW A-RATE VARIABLE 'adlt' IS CREATED BY INTERPOLATING THE K-RATE VARIABLE 'kdlt' amod oscil gkFlaDepth, gkFlaRate, 1 ;OSCILLATOR THAT MAKES USE OF THE POSITIVE DOMAIN ONLY TRIANGLE WAVE IN FUNCTION TABLE 1 adlt sum adlt, amod ;STATIC DELAY TIME AND MODULATING DELAY TIME ARE SUMMED ;REMEMBER THAT THE LENGTH OF THE DELAY BUFFER DEFINED WILL HAVE TO TAKE ACCOUNT OF THE SUMMED MAXIMUM OF THE STATIC DELAY TIME AND MODULATING DELAY TIME ;;;LEFT CHANNEL DELAY;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; abufferL delayr 1.2 ;CREATE A DELAY BUFFER OF 5 SECONDS DURATION (EQUIVALENT TO THE MAXIMUM DELAY TIME POSSIBLE USING THIS EXAMPLE) adelsigL deltap3 adlt ;TAP THE DELAY LINE AT gkdlt SECONDS delayw gasigL + afeedbacksigL ;WRITE AUDIO SOURCE AND FEEDBACK SIGNAL INTO THE BEGINNING OF THE BUFFER abufferR delayr 1.2 ;CREATE A DELAY BUFFER OF 5 SECONDS DURATION (EQUIVALENT TO THE MAXIMUM DELAY TIME POSSIBLE USING THIS EXAMPLE) adelsigR deltap3 adlt ;TAP THE DELAY LINE AT gkdlt SECONDS delayw gasigR + afeedbacksigR ;WRITE AUDIO SOURCE AND FEEDBACK SIGNAL INTO THE BEGINNING OF THE BUFFER afeedbacksigL = adelsigL * gkfeedamt ;CREATE FEEDBACK SIGNAL (AN ATTENUATED PROPORTION OF THE DELAY OUTPUT SIGNAL) afeedbacksigR = adelsigR * gkfeedamt ;CREATE FEEDBACK SIGNAL (AN ATTENUATED PROPORTION OF THE DELAY OUTPUT SIGNAL) outs ((adelsigL * gkmix) + (gasigL * (1-gkmix))) * gkamp, ((adelsigR * gkmix) + (gasigR * (1-gkmix))) * gkamp ;CREATE A MIX BETWEEN THE WET AND THE DRY SIGNALS AT THE OUTPUT gasigL = 0 ;CLEAR THE GLOBAL AUDIO SEND VARIABLES gasigR = 0 ;CLEAR THE GLOBAL AUDIO SEND VARIABLES endin ;INSTR | START | DURATION i 2 0 -1 ;INSTRUMENT 2 PLAYS A HELD NOTE f 1 0 131072 7 0 65536 1 65536 0 ;POSITIVE DOMAIN TRIANGLE WAVE f 0 3600 ;'DUMMY' SCORE EVENT KEEPS REALTIME PERFORMANCE GOING FOR 1 HOUR