BasicMonophonicSynth.csd Written by Iain McCurdy 2006. Updated 2011 -odac -Ma -dm0 ;-odac -M0 -+rtmidi=virtual -dm0 sr = 44100 ksmps = 16 nchnls = 1 0dbfs = 1 ;MAXIMUM AMPLITUDE REGARDLESS OF BIT DEPTH maxalloc 2,1 ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; FLcolor 255, 255, 255, 100, 200, 200 ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "Basic Monophonic MIDI Synthesizer", 500, 60, 0, 0 ;VALUE DISPLAY BOXES WIDTH | HEIGHT | X | Y idporttime FLvalue " ", 60, 18, 5, 35 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkporttime,ihporttime FLslider "Portamento Time", 0, 1, 0, 23, idporttime, 490, 25, 5, 10 ;SET INITIAL VALUES VALUE | HANDLE FLsetVal_i .01, ihporttime FLpanel_end ;INSTRUCTIONS AND INFO PANEL FLpanel " ", 515, 760, 512, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " Basic Monophonic MIDI controlled Synthesizer ", 1, 5, 14, 490, 20, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 20, 5, 20 ih FLbox "NOTE: THIS IS A RE-WRITTEN VERSION OF AN OLDER EXAMPLE. THE ", 1, 5, 14, 490, 20, 5, 40 ih FLbox "OLD METHOD WOULD RESULT IN NON-SOUNDING NOTES IF A NEW PHRASE", 1, 5, 14, 490, 20, 5, 60 ih FLbox "WAS BEGUN OVER THE RELEASE STAGE OF A PREVIOUS PHRASE. ", 1, 5, 14, 490, 20, 5, 80 ih FLbox " ", 1, 5, 14, 490, 20, 5, 100 ih FLbox "You will need to have a midi keyboard connected to the ", 1, 5, 14, 490, 20, 5, 120 ih FLbox "computer for this to work. ", 1, 5, 14, 490, 20, 5, 140 ih FLbox "Monosynths can be implemented using 2 separate instruments. ", 1, 5, 14, 490, 20, 5, 160 ih FLbox "The first instrument is triggered by notes played on a MIDI ", 1, 5, 14, 490, 20, 5, 180 ih FLbox "keyboard, is polyphonic but does not produce any sound. This ", 1, 5, 14, 490, 20, 5, 200 ih FLbox "instrument tracks the most recent MIDI pitch value played and", 1, 5, 14, 490, 20, 5, 220 ih FLbox "is also crucial in being able to inform Csound how many notes", 1, 5, 14, 490, 20, 5, 240 ih FLbox "are being held. It also generates a flag (a momentary '1' ", 1, 5, 14, 490, 20, 5, 260 ih FLbox "value) whenever a new note has been played. ", 1, 5, 14, 490, 20, 5, 280 ih FLbox "The second instrument is the one that actually produces ", 1, 5, 14, 490, 20, 5, 300 ih FLbox "sound. It plays just a single held note and is effectively ", 1, 5, 14, 490, 20, 5, 320 ih FLbox "on all the time. When no notes are played its amplitude ", 1, 5, 14, 490, 20, 5, 340 ih FLbox "envelope returns to zero thereby creating the impression that", 1, 5, 14, 490, 20, 5, 360 ih FLbox "it has stopped playing. ", 1, 5, 14, 490, 20, 5, 380 ih FLbox "A mechanism could be created to turn this instrument off when", 1, 5, 14, 490, 20, 5, 400 ih FLbox "no notes are playing and envelope release stages have ", 1, 5, 14, 490, 20, 5, 420 ih FLbox "returned to zero but in this example it is not really ", 1, 5, 14, 490, 20, 5, 440 ih FLbox "necessary. ", 1, 5, 14, 490, 20, 5, 460 ih FLbox "Portamento (portk) is used in the second instrument to ", 1, 5, 14, 490, 20, 5, 480 ih FLbox "implement glisandi between overlapping notes. ", 1, 5, 14, 490, 20, 5, 500 ih FLbox "There are two ways in which envelopes can be triggered in ", 1, 5, 14, 490, 20, 5, 520 ih FLbox "monophonic synths: ", 1, 5, 14, 490, 20, 5, 540 ih FLbox "1 - triggered only once, at the beginning of a sequence of ", 1, 5, 14, 490, 20, 5, 560 ih FLbox "overlapping notes (legato phrase). ", 1, 5, 14, 490, 20, 5, 580 ih FLbox "2 - triggered with each new note that is pressed whether ", 1, 5, 14, 490, 20, 5, 600 ih FLbox "overlapping or not. ", 1, 5, 14, 490, 20, 5, 620 ih FLbox "The three different envelopes used by the synth exemplify ", 1, 5, 14, 490, 20, 5, 640 ih FLbox "these two ways in which envelopes can be triggered. ", 1, 5, 14, 490, 20, 5, 660 ih FLbox "1 - The amplitude and filter envelopes will be triggered only", 1, 5, 14, 490, 20, 5, 680 ih FLbox "once per legato phrase. ", 1, 5, 14, 490, 20, 5, 700 ih FLbox "2 - A vibrato depth envelope is triggered each time a new ", 1, 5, 14, 490, 20, 5, 720 ih FLbox "note is is pressed whether it overlaps another note or not. ", 1, 5, 14, 490, 20, 5, 740 FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; gkcps init 0 ;INITIALISE GLOBAL VARIABLES gisine ftgen 0,0,4096,10,1 instr 1 ;NOTE ON/OFF AND PITCH REGISERING INSTRUMENT. THIS INSTRUMENT WILL BE TRIGGERED BY NOTE PLAYED ON THE MIDI KEYBOARD icps cpsmidi ;READ IN MIDI PITCH VALUES gkcps = icps ;CREATE A K-RATE GLOBAL VARIABLE VERSION OF MIDI PITCH THAT WILL BE USED IN INSTRUMENT 2. gkNoteOn init 1 ;A FLAG TO INDICATE WHEN A NEW NOTE HAS BEEN PLAYED. THIS FLAG IS CLEARED (RESET TO ZERO) AT THE BOTTOM OF INSTR 2. event_i "i",2,0,-1 ;THE VERY FIRST MIDI NOTE PLAYED WILL TRIGGER AN INFINITELY HELD NOTE IN INSTR 2. THE maxalloc SETTING IN THE ORCHESTRA HEADER WILL PREVENT ANY FURTHER TRIGGERINGS. endin instr 2 ;SOUND PRODUCING INSTRUMENT ;VIBRATO ENVELOPE CHARACTERISTICS ivibamp init 0.05 ivibdelayTim init 0.3 ivibRiseTim init 1.2 kvibfreq init 6 ;AMPLITUDE ENVELOPE CHARACTERISTICS iAmpAttTim init 0.01 iAmpRelTim init 1 ;RESONANT LOWPASS FILTER ENVELOPE CHARACTERISTICS (ADSR TYPE) iFiltAttTim init 0.01 ;FILTER ENVELOPE ATTACK TIME iFiltAttLev init 1 ;ATTACK LEVEL FOR THE FILTER ENVELOPE (RANGE 0 - 1) iFiltDecTim init 2 ;FILTER ENVELOPE DECAY TIME iFiltRelTim init 1 ;FILTER ENVELOPE RELEASE TIME iFiltSusLev init 0.7 ;SUSTAIN LEVEL FOR THE FILTER ENVELOPE (RANGE 0 - 1) iFiltBase init 4 ;BASIC FILTER CUTOFF OFFSET IN OCT FORMAT. ENVELOPE WILL BE ADDED TO THIS VALUE. iFiltEnvRange init 10 ;RANGE OF THE ENVELOPE'S INFLUENCE IN OCT FORMAT kres init 0.9 ;FILTER RESONANCE kactive1 active 1 ;CONTINUALLY TRACK THE NUMBER OF ACTIVE INSTANCES OF INSTRUMENT 1. I.E. THE NUMBER OF MIDI NOTES HELD. ;CREATE PORTAMENTO ON PITCH PARAMETER kporttime linseg 0,0.01,1 ;PORTAMENTO TIME RISES QUICKLY TO A HELD VALUE OF '1' kporttime = kporttime*gkporttime ;PORTAMENTO TIME FUNCTION SCALED BY VALUE OUTPUT BY FLTK SLIDER kcps portk gkcps, kporttime ;APPLY PORTAMENTO TO PITCH CHANGES ;SENSE WHEN TO RE-TRIGGER THE VIBRATO ENVELOPE... if gkNoteOn=1 then ;IF A NEW NOTE HAS BEGUN... reinit RestartVibEnv ;RESTART THE VIBRATO ENVELOPE FROM LABEL 'RestartVibEnv' endif ;END OF THIS CONDITIONAL BRANCH ;CREATE A VIBRATO FUNCTION - THIS ENVELOPE WILL BE TRIGGERED WITH EACH NEW NEW THAT IS PRESSED WHETHER LEGATO OR NOT RestartVibEnv: ;REINITIALISE FROM HERE IF A NEW NOTE HAS BEGUN - THIS WILL RESTART THE VIBRATO ENVELOPE kvibenv transeg 0,ivibdelayTim,0,0,ivibRiseTim,2,ivibamp ;SLIGHTLY CONCAVE BUILD-UP (shape=2) rireturn ;RETURN FROM REINITIALISATION PASS kvib oscil kvibenv, kvibfreq, gisine ;CREATE VIBRATO FUNCTION kvib = kvib+1 ;SHIFT VIBRATO FUNCTION UP THE Y-AXIS SO THAT IT OSCILLATES ABOUT 1 ;CREATE A SAWTOOTH OSCILLATOR USING THE vco2 OPCODE asig vco2 0.3,kcps*kvib kAmpEnv init 0 ;INITIAL ENVELOPE STATE kFiltEnv init 0 ;INITIAL ENVELOPE STATE if gkNoteOn=1&&kactive1=1 then ;IF A NEW LEGATO PHRASE IS BEGUN (I.E. A NEW NOTE HAS BEEN PRESSED AND NO OTHER PREVIOUS NOTES ARE BEING HELD)... reinit RestartLegEnvs ;RESTART THE 'LEGATO PHRASE' ENVELOPES (IN THIS CASE AMPLITUDE AND FILTER) endif ;END OF THIS CONDITIONAL BRANCH RestartLegEnvs: ;A LABEL: BEGIN A REINITIALISATION PASS FROM HERE TO RESTART THE LEGATO PHRASE ENVELOPES if kactive1>0 then ;IF A NEW LEGATO PHRASE IS BEGINNING... kAmpEnv transeg i(kAmpEnv),iAmpAttTim,-2,1 ;MOVE THROUGH AMPLITUDE ATTACK (NOTE ON) ENVELOPE. IT WILL HOLD THE FINAL VALUE kAmpSus = kAmpEnv ;REGISTER OF THE FINAL VALUE OF THE ATTACK-SUSTAIN ENVELOPE - USED BY THE RELEASE STAGE OF THE ENVELOPE kFiltEnv transeg i(kFiltEnv),iFiltAttTim,-2,iFiltAttLev,iFiltDecTim,-2,iFiltSusLev;MOVE THROUGH FILTER ATTACK (NOTE ON) ENVELOPE. IT WILL HOLD THE FINAL VALUE kFiltSus = kFiltEnv ;REGISTER OF THE FINAL VALUE OF THE ATTACK-SUSTAIN ENVELOPE - USED BY THE RELEASE STAGE OF THE ENVELOPE elseif kactive1=0 then ;OR IF A LEGATO PHRASE HAS FINISHED (NO NOTE ARE BEGIN HELD)... kAmpEnv transeg 1,iAmpRelTim,-2,0 ;MOVE THROUGH AMPLITUDE RELEASE ENVELOPE (FINAL VALUE WILL BE HELD) kAmpEnv = kAmpEnv*kAmpSus ;RELEASE ENVELOPE RESCALED ACCORDING TO THE FINAL VALUE OF THE ATTACK SUSTAIN PORTION OF THE ENVELOPE BEFORE THE NOTE OFF WAS RECEIVED kFiltEnv transeg iFiltSusLev,iFiltRelTim,-2,0 ;MOVE THROUGH FILTER RELEASE ENVELOPE (FINAL VALUE WILL BE HELD) kFiltEnv = kFiltEnv*kFiltSus ;RELEASE ENVELOPE RESCALED ACCORDING TO THE FINAL VALUE OF THE ATTACK SUSTAIN PORTION OF THE ENVELOPE BEFORE THE NOTE OFF WAS RECEIVED endif ;END OF THIS CONDITIONAL BRANCH rireturn ;RETURN FROM REINITIALISATION PASS aAmpEnv interp kAmpEnv ;SMOOTHER A-RATE AMPLITUDE ENVELOPE - MAY PROVE BENEFICIAL IF THERE ARE FAST CHANGING ENVELOPE SEGMENTS kFiltEnvScl = cpsoct((kFiltEnv*iFiltEnvRange)+iFiltBase) ;FILTER ENVELOPE RESCALED AND CONVERTED FROM OCT FORMAT TO CPS ;CREATE A FILTERED VERSION OF THE OSCILLATOR SIGNAL asig moogladder asig,kFiltEnvScl,kres ;MOOG LOWPASS FILTER SIGNAL out asig*aAmpEnv ;SEND AUDIO TO OUTPUT gkNoteOn = 0 ;CLEAR NOTE ON FLAG endin f 0 3600 ;DUMMY SCORE EVENT - REAL TIME PERFORMANCE FOR 1 HOUR ;i 2 0 3600 ;SOUND PRODUCING INSTRUMENT IS ALWAYS ON