delayfeedback.csd Written by Iain McCurdy, 2006 THE delay OPCODE IS PLACED IN A SEPARATE, ALWAYS ON, INSTRUMENT FROM THE SOURCE SOUND PRODUCING INSTRUMENT. THE IS A COMMONLY USED TECHNIQUE WITH TIME SMEARING OPCODES AND EFFECTS LIKE REVERBS AND DELAYS. ksmps MAY NEED TO BE LOW (AND kr THEREFORE HIGH) WHEN WORKING WITH SHORT DELAY TIMES DEFINED INITIALLY AT KRATE -iadc -odac -dm0 sr = 44100 ;SAMPLE RATE ksmps = 4 ;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) 0dbfs = 1 ;MAXIMUM AMPLITUDE ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; FLcolor 255, 255, 255, 0, 0, 0 ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "delay with feedback", 500, 300, 0, 0 ; ON | OFF | TYPE | WIDTH | HEIGHT | X | Y | OPCODE | INS | STARTTIM | DUR gkOnOff,ihOnOff FLbutton "Input On/Off", 1, 0, 22, 180, 25, 5, 5, 0, 1, 0, -1 FLsetColor2 255, 255, 50, ihOnOff ;SET SECONDARY COLOUR TO YELLOW ;GENERAL_TEXT_SETTINGS SIZE | FONT | ALIGN | RED | GREEN | BLUE FLlabel 13, 1, 3, 255, 255, 255 ;LABELS MADE INVISIBLE (I.E. SAME COLOR AS PANEL) ;BUTTON BANKS TYPE | NUMX | NUMY | WIDTH | HEIGHT | X | Y | OPCODE | INS | STARTTIM | DUR gkinput, ihinput FLbutBank 14, 1, 2, 18, 40, 250, 0, -1 ;GENERAL_TEXT_SETTINGS SIZE | FONT | ALIGN | RED | GREEN | BLUE FLlabel 13, 1, 3, 0, 0, 0 ;LABELS MADE VISIBLE AGAIN ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox "Input", 1, 5, 14, 50, 16, 200, 0 ih FLbox "Drum Loop", 1, 5, 14, 75, 16, 270, 0 ih FLbox "Live ", 1, 5, 14, 75, 16, 270, 20 ;VALUE_DISPLAY_BOXES WIDTH | HEIGHT | X | Y iddlt FLvalue " ", 80, 20, 5, 75 idmix FLvalue " ", 80, 20, 5, 125 idfeedbackamt FLvalue " ", 80, 20, 5, 175 idamp FLvalue " ", 80, 20, 5, 225 idporttime FLvalue " ", 80, 20, 5, 275 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkdlt,ihdlt FLslider "Delay Time (sec)", .001, 1, -1, 23, iddlt, 490, 25, 5, 50 gkmix,ihmix FLslider "Dry/Wet Mix", 0, 1, 0, 23, idmix, 490, 25, 5, 100 gkfeedamt,ihfeedamt FLslider "Feedback Ratio", -1, 1, 0, 23, idfeedbackamt, 490, 25, 5, 150 gkamp,ihamp FLslider "Output Amplitude Rescaling", 0, 1, 0, 23, idamp, 490, 25, 5, 200 gkporttime,ihporttime FLslider "Portamento Time", 0, 2, 0, 23, idporttime, 490, 25, 5, 250 gkingain,ihingain FLslider "Live Input Gain", 0, 1, 0, 23, -1, 140, 20, 350, 5 ;SET_INITIAL_VALUES VALUE | HANDLE FLsetVal_i .5, ihdlt FLsetVal_i 0.5, ihmix FLsetVal_i 0.7, ihfeedamt FLsetVal_i .7, ihamp FLsetVal_i 0.3, ihporttime 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 - delay with feedback ", 1, 5, 14, 490, 15, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 15, 5, 20 ih FLbox "This example adds a feedback loop. Some of the audio signal ", 1, 5, 14, 490, 15, 5, 40 ih FLbox "present at the delay tap is fed back into the input of the ", 1, 5, 14, 490, 15, 5, 60 ih FLbox "delay buffer. The amount of signal fed back is controlled by ", 1, 5, 14, 490, 15, 5, 80 ih FLbox "the 'Feedback Ratio' slider. A value of zero represents 0% of", 1, 5, 14, 490, 15, 5, 100 ih FLbox "the signal being fed back and a value of 1 represents 100% of", 1, 5, 14, 490, 15, 5, 120 ih FLbox "the signal being fed value. Negative values are also allowed ", 1, 5, 14, 490, 15, 5, 140 ih FLbox "and represent the signal being inverted as it is fed back. ", 1, 5, 14, 490, 15, 5, 160 ih FLbox "The audible effect of this is most evident when working with ", 1, 5, 14, 490, 15, 5, 180 ih FLbox "very short delay times. ", 1, 5, 14, 490, 15, 5, 200 ih FLbox "In this example the user can choose between a drum loop sound", 1, 5, 14, 490, 15, 5, 220 ih FLbox "file as input or the computer's live input. A gain control is", 1, 5, 14, 490, 15, 5, 240 ih FLbox "is provided to control the gain of the live input. ", 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=0 then ;SENSE FLTK ON/OFF SWITCH turnoff ;TURN THIS INSTRUMENT OFF IMMEDIATELY endif if gkinput==0 then ;IF INPUT '808loop.wav' IS SELECTED... gasigL, gasigR diskin2 "808loop.wav", 1, 0, 1 ;GENERATE 2 AUDIO SIGNALS FROM A STEREO SOUND FILE (NOTE THE USE OF GLOBAL VARIABLES) else ;OTHERWISE asigL, asigR ins ;TAKE INPUT FROM COMPUTER'S AUDIO INPUT gasigL = asigL * gkingain ;SCALE USING 'Input Gain' SLIDER gasigR = asigR * gkingain ;SCALE USING 'Input Gain' SLIDER endif ;END OF CONDITIONAL BRANCHING endin instr 2 ;DELAY INSTRUMENT kporttime linseg 0, .001, 1, 1, 1 ;USE OF AN ENVELOPE VALUE THAT QUICKLY RAMPS UP FROM ZERO TO 1. THIS PREVENTS VARIABLES GLIDING TO THEIR REQUIRED VALUES EACH TIME THE INSTRUMENT IS STARTED. kporttime = kporttime * gkporttime ;SCALE PORTAMENTO FUNCTION WITH FLTK SLIDER VALUE 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' ;;;LEFT CHANNEL DELAY;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; abufferL delayr 1 ;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 + (adelsigL * gkfeedamt) ;WRITE AUDIO SOURCE AND FEEDBACK SIGNAL INTO THE BEGINNING OF THE BUFFER ;;;RIGHT CHANNEL DELAY;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; abufferR delayr 1 ;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 + (adelsigR * gkfeedamt) ;WRITE AUDIO SOURCE AND FEEDBACK SIGNAL INTO THE BEGINNING OF THE BUFFER aL ntrpol gasigL, adelsigL, gkmix aR ntrpol gasigR, adelsigR, gkmix outs aL * gkamp, aR * gkamp ;CREATE A MIX BETWEEN THE WET AND THE DRY SIGNALS AT THE OUTPUT clear gasigL, gasigR ;CLEAR THE GLOBAL AUDIO SEND VARIABLES endin ;INSTR | START | DURATION i 2 0 -1 ;INSTRUMENT 2 (DELAY INSTRUMENT) PLAYS A HELD NOTE f 0 3600 ;'DUMMY' SCORE EVENT KEEPS REALTIME PERFORMANCE GOING FOR 1 HOUR