sr	=	44100	 	 
kr	=	4410	 	 
ksmps	=	10	 	 
nchnls	=	2	 	 

;===================================================;
;Simple chorus instrument based on heterodyning.    ;
;With 2 sine waves slightly detuned, the resultant  ;
;frequency will be the average of the 2 sine wave   ;
;frequencies and the beat frequency will be equal   ;
;to the difference between their frequencies:       ;
;sin(a) + sin(b) = 2 * sin((a+b)/2) * cos ((a-b)/2) ;
;Note: we hear two beats for each cos cycle - one   ;
;for the positive peak and one for the negative.    ;
;RP                                                 ;
;===================================================;
 	 	 	 	 
 	instr	1	 	 
;---------------------------------------;initialization block: 				
ipan	=	p9	 	 
ilfac	=	sqrt(p9) 	 	 
irfac	=	sqrt(1-p9)	 	 
idetune	=	p10			;detune factor in CPS	
;---------------------------------------;performance block:				
kgate	linen	p4,p6,p3,p7	 	 
asig1	oscili	kgate,cpspch(p5),p8		;in tune oscil	 
asig2	oscili	kgate,cpspch(p5)+idetune,p8	;out of tune oscil	
asig	=	asig1+asig2		;sum will beat at idetune CPS	
 	outs	asig*ilfac,asig*irfac	;stereo placement and out	
 	endin

;Test score for simple chorus instrument
;Oscil wave functions:
;Simple sine
f1	0	8192	10	1
;Richer waveform									
f2	0	8192	10	1	.5	0	.1	 	 
;Test with pure sine wave
;no	st	dur	amp	pch	rise	dec	fn	pan	detune
i01	0	3	20000	8.00	.1	.5	1	.5	5
i01	+	.	.	.	.	.	.	.	3
i01	.	.	.	.	.	.	.	.	1
i01	.	.	.	.	.	.	.	.	.5
f0	14
s
;Repeat with richer waveform (note: beating between all component partials)
;no	st	dur	amp	pch	rise	dec	fn	pan	detune
i01	0	3	20000	8.00	.1	.5	2	.5	5
i01	+	.	.	.	.	.	.	.	3
i01	.	.	.	.	.	.	.	.	1
i01	.	.	.	.	.	.	.	.	.5
f0	14
e