StereoPingPongDelay.csd Written by Iain McCurdy, 2008 THE DELAY 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 = 32 ;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 gimaxdelay = 5 ;MAXIMUM DELAY TIME VARIABLE USED BOTH BY THE ORCHESTRA CODE AND BY FLTK WIDGET CODE IN THE HEADER ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; FLcolor 255, 255, 255, 250, 50, 50 ;SETUP BASIC COLOURS ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "Stereo Ping-Pong Delay", 500, 300, 0, 0 ; ON | OFF | TYPE | WIDTH | HEIGHT | X | Y | OPCODE | INS | STARTTIM | DUR gkImpulse,ihImpulse FLbutton "Short Impulse Sound", 1, 0, 21, 200, 40, 5, 5, 0, 1, 0, 0.1 ;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 gkmethod, ihmethod FLbutBank 11, 1, 2, 18, 2*15, 70, 45+2, 0, 4, 0, 0 gkSyncNdx, gihSyncNdx FLbutBank 11, 1, 3, 18, 3*15, 270, 45+2, -1 gkLFO_Shape, gihLFO_Shape FLbutBank 11, 1, 2, 18, 2*15, 400, 45+2, -1 FLhide gihSyncNdx FLhide gihLFO_Shape ;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 "Method:", 1, 6, 12, 60, 15, 5, 45+2 ih FLbox "Multi-delay", 1, 5, 12, 80, 15, 90, 45+2 ih FLbox "LFO ", 1, 5, 12, 80, 15, 90, 60+2 gih1 FLbox "LFO Sync:", 1, 6, 12, 70, 15, 200, 45+2 gih2 FLbox "1/2", 1, 5, 12, 30, 15, 290, 45+2 gih3 FLbox "1/4", 1, 5, 12, 30, 15, 290, 60+2 gih4 FLbox "1/8", 1, 5, 12, 30, 15, 290, 75+2 gih5 FLbox "LFO Shape:", 1, 6, 12, 70, 15, 330, 45+2 gih6 FLbox "Sine ", 1, 5, 12, 60, 15, 420, 45+2 gih7 FLbox "Square", 1, 5, 12, 60, 15, 420, 60+2 FLhide gih1 FLhide gih2 FLhide gih3 FLhide gih4 FLhide gih5 FLhide gih6 FLhide gih7 ;VALUE_DISPLAY_BOXES WIDTH | HEIGHT | X | Y iddlt FLvalue " ", 70, 20, 5, 125 idmix FLvalue " ", 70, 20, 5, 175 idfeedbackamt FLvalue " ", 70, 20, 5, 225 idamp FLvalue " ", 70, 20, 5, 275 idInGain FLvalue " ", 50, 20, 210, 25 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkdlt,ihdlt FLslider "Delay Time (sec.)", .001,gimaxdelay, -1, 23, iddlt, 490, 25, 5, 100 gkmix,ihmix FLslider "Dry/Wet Mix", 0, 1, 0, 23, idmix, 490, 25, 5, 150 gkfeedamt,ihfeedamt FLslider "Feedback Amount", -1, 1, 0, 23, idfeedbackamt, 490, 25, 5, 200 gkamp,ihamp FLslider "Output Amplitude Rescaling", 0, 1, 0, 23, idamp, 490, 25, 5, 250 gkInGain,ihInGain FLslider "Live Input Gain", 0, 1, 0, 23, idInGain, 285, 20, 210, 5 ;SET_INITIAL_VALUES VALUE | HANDLE FLsetVal_i .33, ihdlt FLsetVal_i 0.5, ihmix FLsetVal_i 0.66, ihfeedamt FLsetVal_i .7, ihamp FLsetVal_i 0, ihInGain FLsetVal_i 0, gihSyncNdx FLsetVal_i 1, gihLFO_Shape FLpanel_end ;END OF PANEL CONTENTS ;INSTRUCTIONS AND INFO PANEL FLpanel " ", 515, 540, 512, 0 FLscroll 515, 540, 0, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " Stereo Ping-Pong Delay ", 1, 6, 14, 490, 30, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 20, 5, 20 ih FLbox "This example offers two different implementations of a stereo", 1, 5, 14, 490, 20, 5, 40 ih FLbox "ping-pong delay. ", 1, 5, 14, 490, 20, 5, 60 ih FLbox " ", 1, 5, 14, 490, 20, 5, 80 ih FLbox "Method 1 ", 1, 8, 14, 490, 20, 5, 100 ih FLbox "This method echoes input signals alternately in the left and ", 1, 5, 14, 490, 20, 5, 120 ih FLbox "right channels. It does this using a total of three delay ", 1, 5, 14, 490, 20, 5, 140 ih FLbox "buffers: one for the left channel with a feedback loop, one ", 1, 5, 14, 490, 20, 5, 160 ih FLbox "for the right channel with a feedback loop and a third one to", 1, 5, 14, 490, 20, 5, 180 ih FLbox "create an initial delay offset in the left or right channel. ", 1, 5, 14, 490, 20, 5, 200 ih FLbox "The first echo we will hear will be in the channel with the ", 1, 5, 14, 490, 20, 5, 220 ih FLbox "offset. The offsetting delay buffer has no feedback loop but ", 1, 5, 14, 490, 20, 5, 240 ih FLbox "its output is sent separately to the speakers. ", 1, 5, 14, 490, 20, 5, 260 ih FLbox "The schematic is shown below: ", 1, 5, 14, 490, 20, 5, 280 ih FLbox " (feedback) ", 1, 5, 14, 490, 20, 5, 300 ih FLbox " +-------<------+ ", 1, 5, 14, 490, 20, 5, 320 ih FLbox " | | ", 1, 5, 14, 490, 20, 5, 340 ih FLbox " +--------+ v +--------+ ^ ", 1, 5, 14, 490, 20, 5, 360 ih FLbox " |OFFSET | | | | | ", 1, 5, 14, 490, 20, 5, 380 ih FLbox " +----+DELAY +-+-+--+DELAY L +--+--+->LEFT_OUT ", 1, 5, 14, 490, 20, 5, 400 ih FLbox " | |time x 1| | |time x 2| | ", 1, 5, 14, 490, 20, 5, 420 ih FLbox " | +--------+ v +--------+ ^ ", 1, 5, 14, 490, 20, 5, 440 ih FLbox " | | | ", 1, 5, 14, 490, 20, 5, 460 ih FLbox " IN->-+ +--------->---------+ ", 1, 5, 14, 490, 20, 5, 480 ih FLbox " | ", 1, 5, 14, 490, 20, 5, 500 ih FLbox " | +--------+ ", 1, 5, 14, 490, 20, 5, 520 ih FLbox " | | | ", 1, 5, 14, 490, 20, 5, 540 ih FLbox " +-----------------+--+DELAY R +--+---->RIGHT_OUT ", 1, 5, 14, 490, 20, 5, 560 ih FLbox " | |time x 2| | ", 1, 5, 14, 490, 20, 5, 580 ih FLbox " | +--------+ | ", 1, 5, 14, 490, 20, 5, 600 ih FLbox " | | ", 1, 5, 14, 490, 20, 5, 620 ih FLbox " +-------<------+ ", 1, 5, 14, 490, 20, 5, 640 ih FLbox " (feedback) ", 1, 5, 14, 490, 20, 5, 660 ih FLbox " ", 1, 5, 14, 490, 20, 5, 680 ih FLbox "The delay time for the offsetting delay is the same as that ", 1, 5, 14, 490, 20, 5, 700 ih FLbox "defined by the on-screen slider for delay time. The delay ", 1, 5, 14, 490, 20, 5, 720 ih FLbox "times for the other two delays with feedback are twice the ", 1, 5, 14, 490, 20, 5, 740 ih FLbox "value defined by the slider. When the echoes alternate ", 1, 5, 14, 490, 20, 5, 760 ih FLbox "the perceived delay time will be the same as that defined by ", 1, 5, 14, 490, 20, 5, 780 ih FLbox "the slider. ", 1, 5, 14, 490, 20, 5, 800 ih FLbox "The input sound for the effect in this example can be either ", 1, 5, 14, 490, 20, 5, 820 ih FLbox "a short synthesised impulse triggered by the button or the ", 1, 5, 14, 490, 20, 5, 840 ih FLbox "computer's live input controlled by the 'Input Gain' slider. ", 1, 5, 14, 490, 20, 5, 860 ih FLbox " ", 1, 5, 14, 490, 20, 5, 880 ih FLbox "Method 2 ", 1, 8, 14, 490, 20, 5, 900 ih FLbox "This method pans a single delay with a panning rate that ", 1, 5, 14, 490, 20, 5, 920 ih FLbox "synchronises to the delay time using some simple ratio. For ", 1, 5, 14, 490, 20, 5, 940 ih FLbox "example if a sync. ratio of 1/2 is chosen then the period of ", 1, 5, 14, 490, 20, 5, 960 ih FLbox "the LFO is twice that of the delay time - for each echo the ", 1, 5, 14, 490, 20, 5, 980 ih FLbox "LFO will have moved on 180 degrees. If the ratio is 1/4 then ", 1, 5, 14, 490, 20, 5,1000 ih FLbox "the LFO moves on 90 degrees for each echo. The LFO shape can ", 1, 5, 14, 490, 20, 5,1020 ih FLbox "be either a sine wave or a square wave. If a square wave is ", 1, 5, 14, 490, 20, 5,1040 ih FLbox "chosen then the delay will only be panned extreme left or ", 1, 5, 14, 490, 20, 5,1060 ih FLbox "extreme right. If sine is chosen then ping-ponging moves ", 1, 5, 14, 490, 20, 5,1080 ih FLbox "smoothly between the left and right. ", 1, 5, 14, 490, 20, 5,1100 ih FLbox "The Schematic is as shown below: ", 1, 5, 14, 490, 20, 5,1120 ih FLbox " ", 1, 5, 14, 490, 20, 5,1140 ih FLbox " +--------+ +--------+ ", 1, 5, 14, 490, 20, 5,1160 ih FLbox " | DELAY | | SYNCED +---->LEFT_OUT ", 1, 5, 14, 490, 20, 5,1180 ih FLbox " MONO_IN->-----+ +---+ LFO | ", 1, 5, 14, 490, 20, 5,1200 ih FLbox " |time x 1| |PANNING +---->RIGHT_OUT ", 1, 5, 14, 490, 20, 5,1220 ih FLbox " +--------+ +--------+ ", 1, 5, 14, 490, 20, 5,1240 ih FLbox " ", 1, 5, 14, 490, 20, 5,1260 FLscrollEnd FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; instr 1 ;GENERATES A SHORT SYNTHESISED IMPULSE SOUND aenv expseg 0.0001, 0.01, 1, p3-0.01, 0.0001 ;PERCUSSIVE-TYPE AMPLITUDE ENVELOPE asig1 noise 0.3 * aenv, 0 ;GENERATE A 'WHITE NOISE' SIGNAL iCutoff_Oct random 6,14 ;CREATE A RANDOM VALUE FOR CUTOFF FREQUENCY (IN OCT FORMAT) asig2 butlp asig1, cpsoct(iCutoff_Oct) ;LOWPASS FILTER WHITE NOISE gasig balance asig2, asig1 ;BALANCE FILTERED SIGNAL WITH UNFILTERED WHITE NOISE SIGNAL TO COMPENSATE FOR AMPLITUDE LOSS endin instr 2 ;STEREO PING-PONG DELAY INSTRUMENT - ALSO READS LIVE INPUT SIGNAL gasig init 0 ;SET INITIAL STATE OF GLOBAL AUDIO SIGNAL (SILENCE) if gkmethod!=0 kgoto SKIP aInL, aInR ins ;READ LIVE AUDIO INPUT aInL = (aInL * gkInGain) + gasig ;MIX LIVE AUDIO IN WITH GLOBAL AUDIO SIGNAL RECEIVED FROM INSTR 1 aInR = (aInR * gkInGain) + gasig ;MIX LIVE AUDIO IN WITH GLOBAL AUDIO SIGNAL RECEIVED FROM INSTR 1 iporttime = .1 ;PORTAMENTO TIME kporttime linseg 0, .001, iporttime ;USE OF AN ENVELOPE VALUE THAT QUICKLY RAMPS UP FROM ZERO TO THE REQUIRED VALUE. THIS 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' ;;;LEFT CHANNEL OFFSET;;;NO FEEDBACK!!;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; abufferL_OS delayr gimaxdelay ;CREATE A DELAY BUFFER OF imaxdelay SECONDS DURATION adelsigL_OS deltap3 adlt ;TAP THE DELAY LINE AT adlt SECONDS delayw aInL ;WRITE AUDIO SOURCE INTO THE BEGINNING OF THE BUFFER ;;;LEFT CHANNEL DELAY;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; abufferL delayr gimaxdelay*2 ;CREATE A DELAY BUFFER OF 5 SECONDS DURATION (EQUIVALENT TO THE MAXIMUM DELAY TIME POSSIBLE USING THIS EXAMPLE) adelsigL deltap3 adlt*2 ;TAP THE DELAY LINE AT gkdlt SECONDS delayw adelsigL_OS + (adelsigL * gkfeedamt) ;WRITE AUDIO SOURCE FROM OFFSETTTING DELAY AND FEEDBACK SIGNAL INTO THE BEGINNING OF THE BUFFER abufferR delayr gimaxdelay*2 ;CREATE A DELAY BUFFER OF 5 SECONDS DURATION (EQUIVALENT TO THE MAXIMUM DELAY TIME POSSIBLE USING THIS EXAMPLE) adelsigR deltap3 adlt*2 ;TAP THE DELAY LINE AT gkdlt SECONDS delayw aInR+(adelsigR*gkfeedamt) ;WRITE AUDIO SOURCE AND FEEDBACK SIGNAL INTO THE BEGINNING OF THE BUFFER ;CREATE LEFT AND RIGHT CHANNEL MIXES aOutL sum (((adelsigL + adelsigL_OS)* gkmix) + (aInL * (1-gkmix))) * gkamp aOutR sum ((adelsigR) * gkmix) + (aInR * (1-gkmix)) * gkamp outs aOutL, aOutR ;CREATE A MIX BETWEEN THE WET AND THE DRY SIGNALS AT THE OUTPUT gasig = 0 ;CLEAR THE GLOBAL AUDIO SEND VARIABLES SKIP: endin instr 3 ;LFO DELAY if gkmethod!=1 kgoto SKIP aLiveIn inch 1 ;READ LIVE AUDIO INPUT FROM LEFT CHANNEL aIn = (aLiveIn * gkInGain) + gasig ;MIX LIVE AUDIO IN WITH GLOBAL AUDIO SIGNAL RECEIVED FROM INSTR 1 iporttime = .1 ;PORTAMENTO TIME kporttime linseg 0, .001, iporttime ;USE OF AN ENVELOPE VALUE THAT QUICKLY RAMPS UP FROM ZERO TO THE REQUIRED VALUE. THIS 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' abuffer delayr gimaxdelay ;CREATE A DELAY BUFFER OF 5 SECONDS DURATION (EQUIVALENT TO THE MAXIMUM DELAY TIME POSSIBLE USING THIS EXAMPLE) adelsig deltap3 adlt ;TAP THE DELAY LINE AT gkdlt SECONDS delayw aIn + (adelsig * gkfeedamt) ;WRITE AUDIO SOURCE AND FEEDBACK SIGNAL INTO THE BEGINNING OF THE BUFFER iSyncVals ftgenonce 0,0,-3,-2,0.5,0.25,0.125;TABLE THAT STORE SYNC VALUES ktrig changed gkSyncNdx,gkLFO_Shape ;IF 'SYNC VALUE' OR 'LFO SHAPE' CONTROLS ARE CHANGED... if ktrig==1 then reinit UPDATE_LFO ;UPDATE THE LFO SET-UP endif UPDATE_LFO: iSyncVal table i(gkSyncNdx),iSyncVals ;READ SYNC VALUE USING SYNC INDEX FROM BUTTON BANK VALUE kpan lfo 0.5,iSyncVal/kdlt,i(gkLFO_Shape)*2;LFO SPEED IS RELATED TO DELAY TIME: IT IS 'SYNC VALUE' TIMES THE RECIPROCAL OF DELAY TIME rireturn aL,aR pan2 adelsig,kpan+0.5 ;PAN THE DELAYED SIGNAL outs aL * gkamp, aR * gkamp SKIP: gasig = 0 ;CLEAR THE GLOBAL AUDIO SEND VARIABLES endin instr 4 if i(gkmethod)==0 then FLhide gihSyncNdx FLhide gihLFO_Shape FLhide gih1 FLhide gih2 FLhide gih3 FLhide gih4 FLhide gih5 FLhide gih6 FLhide gih7 else FLshow gihSyncNdx FLshow gihLFO_Shape FLshow gih1 FLshow gih2 FLshow gih3 FLshow gih4 FLshow gih5 FLshow gih6 FLshow gih7 endif endin ;INSTR | START | DURATION i 2 0 3600 ;SEPARATE DELAYS ON LEFT AND RIGHT CHANNELS PING-PONG DELAY INSTRUMENT i 3 0 3600 ;LFO PING-PONGDELAY INSTRUMENT