RingModulationAmplitudeModulation.csd Written by Iain McCurdy, 2006 -iadc -odac -b400 sr = 44100 ;SAMPLE RATE ksmps = 128 ;CONTROL RATE nchnls = 2 ;NUMBER OF CHANNELS (2=STEREO) ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; FLcolor 255, 255, 255, 0, 0, 0 ;SET INTERFACE COLOURS ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "Amplitude Modulation / Ring Modulation", 500, 360, 0, 0 ;BORDERS ITYPE, IFONT, ISIZE, IWIDTH, IHEIGHT, IX, IY ih FLbox " ", 6, 9, 15, 498, 108, 1, 1 ;CARRIER ih FLbox " ", 6, 9, 15, 498, 108, 1,123 ;MODULATOR ih FLbox " ", 6, 9, 15, 498, 108, 1,244 ;OUTPUT ;TEXT BOXES ITYPE, IFONT, ISIZE, IWIDTH, IHEIGHT, IX, IY ih FLbox "INPUT SIGNAL", 1, 2, 12, 90, 20, 5, 4 ih FLbox "(CARRIER)", 1, 2, 12, 90, 20, 5, 24 ih FLbox "MODULATOR", 1, 2, 12, 90, 20, 5,130 ih FLbox "OUTPUT", 1, 2, 12, 90, 20, 5,250 ;VALUE DISPLAY BOXES LABEL | WIDTH | HEIGHT | X | Y idOscFrq FLvalue " ", 50, 16, 210, 40 idModFrq FLvalue " ", 70, 20, 100, 205 idDryWet FLvalue " ", 70, 20, 100, 275 idOutGain FLvalue " ", 70, 20, 100, 325 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkInGain, ihInGain FLslider "Input Gain", 0, 1, 0, 5, -1, 250, 10, 210, 5 gkOscFrq, ihOscFrq FLslider "Sine Tone Frequency", 1, 10000, -1, 5, idOscFrq, 250, 10, 210, 30 gkModFrq, ihModFrq FLslider "Modulation Frequency", 1, 15000, -1, 25, idModFrq, 390, 25, 100,180 gkDryWet, ihDryWet FLslider "Dry/Wet Mix", 0, 1, 0, 25, idDryWet, 390, 25, 100,250 gkOutGain, ihOutGain FLslider "Output Gain", 0, 1, 0, 25, idOutGain, 390, 25, 100,300 ;GENERAL_TEXT_SETTINGS SIZE | FONT | ALIGN | RED | GREEN | BLUE FLlabel 13, 4, 1, 255, 255, 255 ;NUMBERS MADE INVISIBLE FLcolor2 255, 255, 50 ;SET SECONDARY COLOUR TO YELLOW ; FLBUTBANK TYPE | NUMX | NUMY | WIDTH | HEIGHT | X | Y | OPCODE gkinput, ihinput FLbutBank 12, 1, 4, 30, 100, 100, 5, -1 gkAM_RM, ihAM_RM FLbutBank 12, 1, 2, 30, 50, 100,125, -1 gkwave, ihwave FLbutBank 12, 1, 2, 30, 50, 300,125, -1 ;GENERAL_TEXT_SETTINGS SIZE | FONT | ALIGN | RED | GREEN | BLUE FLlabel 13, 4, 1, 0, 0, 0 ;LABELS MADE VISIBLE AGAIN ;SET INITIAL VALUES FOR VALUATORS VALUE | HANDLE FLsetVal_i 477, ihOscFrq FLsetVal_i 350, ihModFrq FLsetVal_i 1, ihDryWet FLsetVal_i 0.7, ihOutGain FLsetVal_i 1, ihAM_RM ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox "Live Input", 1, 5, 12, 70, 25, 132, 5 ih FLbox "Sine Tone ", 1, 5, 12, 70, 25, 132, 30 ih FLbox "Drum Loop ", 1, 5, 12, 70, 25, 132, 55 ih FLbox "Songpan ", 1, 5, 12, 70, 25, 132, 80 ih FLbox "Amplitude Modulation", 1, 5, 12, 150, 25, 130, 125 ih FLbox "Ring Modulation ", 1, 5, 12, 150, 25, 130, 150 ih FLbox "Sine ", 1, 5, 12, 70, 25, 330, 125 ih FLbox "Triangle", 1, 5, 12, 70, 25, 330, 150 FLpanel_end ;INSTRUCTIONS AND INFO PANEL WIDTH | HEIGHT | X | Y FLpanel " ", 515, 700, 512, 0 FLscroll 515, 700, 0, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " Amplitude Modulation / Ring Modulation ", 1, 5, 14, 490, 20, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 20, 5, 20 ih FLbox "When the frequency of amplitude modulation of an audio signal", 1, 5, 14, 490, 20, 5, 40 ih FLbox "enters the domain of audible frequecies we cease to perceive ", 1, 5, 14, 490, 20, 5, 60 ih FLbox "a rising and falling amplitude but instead perceive the ", 1, 5, 14, 490, 20, 5, 80 ih FLbox "emergence of sideband tones. The frequencies of these tones ", 1, 5, 14, 490, 20, 5, 100 ih FLbox "will be determined by the frequencies of the two input ", 1, 5, 14, 490, 20, 5, 120 ih FLbox "signals and by the waveform used for modulation. These ", 1, 5, 14, 490, 20, 5, 140 ih FLbox "sideband tones will be most clearly discernible when the ", 1, 5, 14, 490, 20, 5, 160 ih FLbox "source sound (carrier) and modulating waveforms are both sine", 1, 5, 14, 490, 20, 5, 180 ih FLbox "tones. ", 1, 5, 14, 490, 20, 5, 200 ih FLbox "Ring modulation is a variation of amplitude modulation in ", 1, 5, 14, 490, 20, 5, 220 ih FLbox "which the modulating signal is bipolar as opposed to ", 1, 5, 14, 490, 20, 5, 240 ih FLbox "unipolar. In ring modulation the amplitude of the input ", 1, 5, 14, 490, 20, 5, 260 ih FLbox "signal is effectively being modulated by a rectified sine ", 1, 5, 14, 490, 20, 5, 280 ih FLbox "wave (the perceived modulations in amplitude therefore being ", 1, 5, 14, 490, 20, 5, 300 ih FLbox "twice the frequency of those from a unipolar modulating ", 1, 5, 14, 490, 20, 5, 320 ih FLbox "signal) - but the signal also becomes inverted when the ", 1, 5, 14, 490, 20, 5, 340 ih FLbox "modulating signal enters the negative domain. ", 1, 5, 14, 490, 20, 5, 360 ih FLbox "Ring modulation derives its name from the 'ring' formation of", 1, 5, 14, 490, 20, 5, 380 ih FLbox "four diodes in its original analog implementation, not from ", 1, 5, 14, 490, 20, 5, 400 ih FLbox "its ability to imbue a source signal with a 'ringing' ", 1, 5, 14, 490, 20, 5, 420 ih FLbox "characteristic. ", 1, 5, 14, 490, 20, 5, 440 ih FLbox "In amplitude modulation between sine waves the frequency of ", 1, 5, 14, 490, 20, 5, 460 ih FLbox "the carrier wave is present at the output and just a single ", 1, 5, 14, 490, 20, 5, 480 ih FLbox "sideband is created equivalent to the sum of the input ", 1, 5, 14, 490, 20, 5, 500 ih FLbox "frequencies. ", 1, 5, 14, 490, 20, 5, 520 ih FLbox "In ring modulation the frequency of the carrier wave is not ", 1, 5, 14, 490, 20, 5, 540 ih FLbox "present at the output and two sidebands are created ", 1, 5, 14, 490, 20, 5, 560 ih FLbox "equivalent to the sum and difference of the input ", 1, 5, 14, 490, 20, 5, 580 ih FLbox "frequencies. ", 1, 5, 14, 490, 20, 5, 600 ih FLbox "In amplitude modulation and ring modulation synthesis and ", 1, 5, 14, 490, 20, 5, 620 ih FLbox "signal processing, the source signal is referred to as the ", 1, 5, 14, 490, 20, 5, 640 ih FLbox "'carrier' and the modulation waveform as the 'modulator'. ", 1, 5, 14, 490, 20, 5, 660 ih FLbox "In this example the user can choose between an amplitude ", 1, 5, 14, 490, 20, 5, 680 ih FLbox "modulation effect and a ring modulation effect. The user can ", 1, 5, 14, 490, 20, 5, 700 ih FLbox "also choose between one of four source signals. ", 1, 5, 14, 490, 20, 5, 720 ih FLbox "As well as modulating the source signal with a sine wave, ", 1, 5, 14, 490, 20, 5, 740 ih FLbox "which is the more common practice, the user can also choose a", 1, 5, 14, 490, 20, 5, 760 ih FLbox "triangle wave as the modulating waveform. ", 1, 5, 14, 490, 20, 5, 780 ih FLbox "Ring modulation is a classic electronic effect employed in ", 1, 5, 14, 490, 20, 5, 800 ih FLbox "the past by some of the giants of electronic music such as ", 1, 5, 14, 490, 20, 5, 820 ih FLbox "Karlheinz Stockhausen and the Daleks. ", 1, 5, 14, 490, 20, 5, 840 FLscrollEnd FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; gisine ftgen 1,0,4097,10,1 ;A SINE WAVE gitri ftgen 2,0,4097,7,0,1024,-1,2048,1,1024,0 ;A TRIANGLE WAVE instr 1 ;THIS INSTRUMENT GENERATES AN AUDIO STREAM FROM A SOUND FILE AND THE LIVE INPUT, CONVERTS THE CHOSEN STREAM INTO AN FSIG, APPLIES THE pvsfreeze OPCODE, RESYNTHESIZES ITS OUTPUT AS AN AUDIO SIGNAL AND SENDS THE OUTPUT TO THE SPEAKERS if gkinput=0 then ;IF FLTK INPUT BUTTON 1 IS SELECTED (LIVE AUDIO IN) asig inch 1 ;READ AUDIO FROM INPUT CHANNEL 1 (LEFT) asig = asig * gkInGain ;RESCALE LIVE AUDIO INPUT AUDIO WITH FLTK 'InGain' SLIDER elseif gkinput=1 then ;IF FLTK INPUT BUTTON 2 IS SELECTED (SINE TONE) asig oscili 10000,gkOscFrq,gisine ;CREATE A SINE TONE OSCILLATOR elseif gkinput=2 then ;IF FLTK INPUT BUTTON 3 IS SELECTED (DRUM LOOP) asig,aR diskin2 "808loop.wav",1,0,1 ;READ '808Loop.wav' FROM DISK else ;ONLY OTHER OPTION IS IF FLTK BUTTON 4 IS SELECTED (SONPAN) asig,aR diskin2 "Songpan.wav",1,0,1 ;READ 'Songpan.wav' FROM DISK endif ;END OF CONDITIONAL BRANCHING if gkAM_RM=0 then ;IF 'Amplitude Modulation' IS SELECTED amod oscilikt 0.5,gkModFrq,gkwave+1 ;CREATE 'Amplitude Modulation' WAVEFORM amod = amod + 0.5 ;OFFSET 'Amplitude Modulation' WAVEFORM else ;ONLY OTHER OPTION IS IF 'Ring Modulation' IS SELECTED amod oscilikt 1,gkModFrq,gkwave+1 ;CREATE RING MODULATION OSCILLATOR endif ;END OF CONDITIONAL BRANCHING aModSig = asig*amod ;MULTIPLY INPUT SIGNAL BY MODULATION SIGNAL amix ntrpol asig, aModSig, gkDryWet ;CREATE DRY/WET MIXED SIGNAL outs amix * gkOutGain, amix * gkOutGain ;SEND DRY/WET MIXED AUDIO SIGNAL TO OUTPUTS AND RESCALE USING 'gkOutGain' ON-SCREEN FLTK SLIDER endin i 1 0 3600 ;INSTR 1 PLAYS FOR UP TO 1 HOUR