;Written by Iain McCurdy, 2006 -idevaudio -odevaudio -b400 sr = 44100 ;SAMPLE RATE ksmps = 100 ;NUMBER OF AUDIO SAMPLES IN EACH CONTROL CYCLE nchnls = 2 ;NUMBER OF CHANNELS (2=STEREO) ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; FLcolor 255, 255, 255, 0, 0, 0 ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "vcomb", 500, 200, 0, 0 ;SWITCHES ON | OFF | TYPE | WIDTH | HEIGHT | X | Y | OPCODE | INS | STARTTIM | DUR gkOnOff,ihOnOff FLbutton "On/Off", 1, 0, 22, 120, 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, 230, 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, 20, 180, 0 ih FLbox "Drum Loop", 1, 5, 14, 75, 20, 250, 0 ih FLbox "Live ", 1, 5, 14, 75, 20, 250, 20 ;VALUE DISPLAY BOXES LABEL | WIDTH | HEIGHT | X | Y idlpt FLvalue " ", 80, 20, 5, 75 idrvt FLvalue " ", 80, 20, 5, 125 idamp FLvalue " ", 80, 20, 5, 175 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gklpt,ihlpt FLslider "Loop Time", .0001, .1, -1, 23, idlpt, 490, 25, 5, 50 gkrvt,ihrvt FLslider "Reverb Time", .0001, 10, -1, 23, idrvt, 490, 25, 5, 100 gkamp,ihamp FLslider "Output Amplitude Scaling", 0, 1, 0, 23, idamp, 490, 25, 5, 150 gkingain,ihingain FLslider "Live Input Gain", 0, 1, 0, 23, -1, 140, 20, 350, 5 ;SET INITIAL VALUES OF FLTK VALUATORS ; VALUE | HANDLE FLsetVal_i .0025, ihlpt FLsetVal_i .2, ihrvt FLsetVal_i .7, ihamp FLpanel_end ;INSTRUCTIONS AND INFO PANEL FLpanel " ", 500, 660, 512, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " vcomb ", 1, 5, 14, 490, 20, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 20, 5, 20 ih FLbox "Vcomb implements a comb filtering effect on an audio input. ", 1, 5, 14, 490, 20, 5, 40 ih FLbox "This is described in the manual as 'coloured reverb'. ", 1, 5, 14, 490, 20, 5, 60 ih FLbox "In effect the comb filter is simply a delay with a feedback ", 1, 5, 14, 490, 20, 5, 80 ih FLbox "loop as illustrated below: ", 1, 5, 14, 490, 20, 5, 100 ih FLbox " +-----+ ", 1, 5, 14, 490, 20, 5, 120 ih FLbox " INPUT-->--+--+DELAY+---+-->OUTPUT ", 1, 5, 14, 490, 20, 5, 140 ih FLbox " | +-----+ | ", 1, 5, 14, 490, 20, 5, 160 ih FLbox " | | ", 1, 5, 14, 490, 20, 5, 180 ih FLbox " +-[FEEDBACK]-+ ", 1, 5, 14, 490, 20, 5, 200 ih FLbox " ", 1, 5, 14, 490, 20, 5, 220 ih FLbox "Delay time is expressed as 'Loop Time' in the context of this", 1, 5, 14, 490, 20, 5, 240 ih FLbox "opcode but it is effectively the same thing as delay time. ", 1, 5, 14, 490, 20, 5, 260 ih FLbox "A ratio for the amount of feedback is not directly accessible", 1, 5, 14, 490, 20, 5, 280 ih FLbox "but instead the user defines a value for 'Reverb Time' which ", 1, 5, 14, 490, 20, 5, 300 ih FLbox "is the time it will take for an impulse's reverberant tail to", 1, 5, 14, 490, 20, 5, 320 ih FLbox "decay to 1/1000 of its initial strength (a 60 dB drop). ", 1, 5, 14, 490, 20, 5, 340 ih FLbox "The use of feedback can create dramatic rises in output ", 1, 5, 14, 490, 20, 5, 360 ih FLbox "amplitude, therefore in this example I have included a slider", 1, 5, 14, 490, 20, 5, 380 ih FLbox "that controls output amplitude. ", 1, 5, 14, 490, 20, 5, 400 ih FLbox "Vcomb produces an audible transformation similar to the ", 1, 5, 14, 490, 20, 5, 420 ih FLbox "'wguide1' and 'streson' opcodes but as it lacks any lowpass ", 1, 5, 14, 490, 20, 5, 440 ih FLbox "filtering within its algorithm it produces a sharper sound. ", 1, 5, 14, 490, 20, 5, 460 ih FLbox "Vcomb differs from the 'comb' opcode in that it allows the ", 1, 5, 14, 490, 20, 5, 480 ih FLbox "user to vary the 'Loop Time' parameter at rates other than ", 1, 5, 14, 490, 20, 5, 500 ih FLbox "i-rate. Because of this vcomb takes an additional input ", 1, 5, 14, 490, 20, 5, 520 ih FLbox "argument in which the user must declare the maximum 'Loop ", 1, 5, 14, 490, 20, 5, 540 ih FLbox "Time that the opcode should expect (for memory allocation ", 1, 5, 14, 490, 20, 5, 560 ih FLbox "purposes). ", 1, 5, 14, 490, 20, 5, 580 ih FLbox "In this example the user can choose between a sound file ", 1, 5, 14, 490, 15, 5, 600 ih FLbox "input or the computer's live input. An input gain control on ", 1, 5, 14, 490, 15, 5, 620 ih FLbox "the live input is also provided. ", 1, 5, 14, 490, 15, 5, 640 FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; instr 1 ;PLAYS FILE AND OUTPUTS GLOBAL VARIABLES if gkOnOff=0 then turnoff ;TURN THIS INSTRUMENT OFF IMMEDIATELY endif if gkinput==0 then ;IF INPUT 'Drum Loop' 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 ;OUTPUT OPCODE | INPUT | REVERB_TIME | LOOP_TIME_(DELAY_TIME) | MAXIMUM_LOOP_TIME aresL vcomb gaSigL, gkrvt, gklpt, .1 aresR vcomb gaSigR, gkrvt, gklpt, .1 outs aresL * gkamp, aresR * gkamp ;SEND vcomb OUTPUT TO THE AUDIO OUTPUTS AND SCALE USING THE FLTK SLIDER VARIABLE gkamp clear gaSigL, gaSigR ;CLEAR GLOBAL AUDIO VARIABLES endin ;INSTR | START | DURATION i 2 0 3600 ;INSTRUMENT 2 PLAYS A HELD NOTE AND KEEPS REALTIME PERFORMANCE GOING FOR 1 HOUR