Additive Synthesis Example

; ADDREV.ORC - Additive Synthesis and Reverberation
; ...some lowpass filtering is also used here...
; By: RST and CUS - MUS499 Seminar

; Initializaton Block - SRATE etc.

sr = 20000
kr = 1000
ksmps = 20
nchnls = 2

; Initialize global variable for reverb send!

garvbsig init 0

; Six OCSILI units are used

instr 1

iamp	=	p4
ifund	=	p5
ifilt	= 	p6
irvb	=	p7
irand	=	22.0 	; pitch deviation
irtime	=	7	; random time element

; General Envelope for Additive Snd.
aenv	linseg	0,p3/2,1,p3/2,0

; Randomizer for random rates below.
aptim	randi	irtime, .01

; Random pitch offset according to randomized time.
; Each OSCILI UG eventually added.
ap1		randi	irand, 2*aptim
asig1 	oscili 	iamp/6, ifund*1.00+ap1,	1

ap2		randi	1rand, 3*aptim
asig2 	oscili 	iamp/6, ifund*1.4+ap2,	1

ap3		randi	1rand, 4*aptim
asig3 	oscili 	iamp/6, ifund*1.7+ap3,	1

ap4		randi	1rand, 5*aptim
asig4 	oscili 	iamp/6, ifund*1.9+ap4,	1

ap5		randi	1rand, 6*aptim
asig5 	oscili 	iamp/6, ifund*2.18+ap5,	1

ap6		randi	1rand, 7*aptim
asig6 	oscili 	iamp/6, ifund*2.39+ap6,	1

; MIX SIGNAL
; APPLY ENVELOPE
amixed	=	asig1+asig2+asig3+asig4+asig5+asig6
aenved	=	amixed*aenv

; Low Pass filter to cut high freq harshness.
asigf	butterlp  aenved, ifilt

; Reverb Send Signal
garvbsig   = 	asigf*irvb

; MIX for MONO OUTPUT!
outs	asigf, asigf

endin

;******************************************************************************
; Reverberation Instrument - two parallel reverbs with tone controls on
; the output of each!
;******************************************************************************

instr 100

  idur 			= p3
  irvbtime1 	= p4
  irev1amp 		= p5
  irev1low 		= p6
  irev1hi 		= p7
  irvbtime2 	= p8
  irev2amp 		= p9
  irev2low 		= p10
  irev2hi 		= p11

; Reverb Section
  arev1	   		reverb2   	garvbsig*irev1amp,  irvbtime1,  .1
  arev2	   		reverb2   	garvbsig*irev2amp,  irvbtime2,  .1

; Post Reverb Tone Controls REV1
  arev1lp		butterlp	arev1,	   irev1low
  arev1hp		butterhp	arev1lp,   irev1hi

; Post Reverb Tone Controls REV2
  arev2lp		butterlp	arev2,	   irev2low
  arev2hp		butterhp	arev2lp,   irev2hi

; MIX for MONO OUTPUT
  asig			= arev1hp+arev2hp
  outs   		asig, asig

  garvbsig = 0

endin

;*******************************************************************************
; AND NOW THE SCORE FILE
;*******************************************************************************

; addrev.sco
; oscili table
f1 0 2048 10 1

; reverb 
;              time amp      lo  hi  	time amp   lo 	hi
i100 0 50	2.3  2.0    1000 20     13.2 2.0   8000 1200

;
i1 0 	10  2000  116  6990  .6
i1 6 	10  2000  398  6990  .6
i1 14 	10  2000  668  6990  .6