GRP Synthesizer A4 User manual

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Grp!A4!Synthesizer!
Owner’s!Manual!
V.!1.09!
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S
VC LOW FREQUENCY OSCILLATOR 1
MIXER
EXT IN - ENV FOLL
CV OUT 0/+8V
CONNECTIONS
CLK IN 0/+5V CLK OUT 0/+5V
LEFT/24db RIGHT/12db
PHONES
GATEIN 0/+5VCV IN 1V/Oct
CV OUT 1V/Oct CV IN 24db
AMT
2
56
7
8
9
10
4
3
1
0
0+1
+2
+3
+4
-1
-2
-3
-4
PW
-5 +5
SOURCE CV
VOLTAGE CONTROLLED AMPLIFIER
RELEASEDECAY SUSTAIN
LEVEL
ATTACK
GATE
SEQ
ENVELOPE GENERATOR 2
AM LFO1
OFF
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
STEREO MAIN
MASTER VOLUME
56
7
8
9
10
4
3
2
1
0
GATE AUTO
10
CV VCA
EG2 HOLD
EXT CV
SAMPLE & HOLD - NOISE
RUN/STOP RESET LOOP ON/OFF
GATE OUT 0/+5V
Grp Synthesizer A4
®
KYBD
VOLTAGE CONTROLLED FILTER
12 db STATE VARIABLE FILTER24 db LOW PASS FILTER
RESONANCE
56
7
8
9
10
4
3
2
1
0
FREQUENCY
56
7
8
9
10
4
3
2
1
0
ROUTING
24db
12db SER
PAR
DIST/LEVEL
AMT
RESONANCE
56
7
8
9
10
4
3
2
1
0
AMT FM3
AMT
MODE
12db HP
6db BP
NOTCH
12db LP
AMT FM3
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
AMOUNT EG
OVERLOAD
6db
12db
24db
18db
SLOPE
FM2 LFO1
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
ATTACK
GATE AUTO
SUSTAINDECAYHOLD RELEASE
LEVEL
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
AMOUNT EG
56
7
8
9
10
4
3
2
1
0
VELOCITY EG
OVERLOAD
KYBD TRK
REVNOR
SEQ
ON
FREQUENCY
56
7
8
9
10
4
3
2
1
0
10
ENVELOPE GENERATOR 1
NOR REV
REV
NOR
REV
NOR
SEQ
KYBD/S&H
EXT IN
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
PHASEPHASE
FM1 FM1
AUDIO PATH
DIROUT
OFF
DIST/LEVEL
DIST DIST
FM2 LFO1
LOOP
ROW ATRNP
CVIN CLK MOD AUDIOEXTIN
OFF
ROW BROW A ROW A + B
TIME
GATE LOOP
KYBD/S&H
EXT IN
INPUT GAIN
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
FREQUENCY
NOISE
56
7
8
9
10
4
3
2
1
0
RING MOD
VCO2 x VCO3/EXT IN
56
7
8
9
10
4
3
2
1
0
VCO 3 EXT INPUT
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
SUB 2VCO 2
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
VCO 1 SUB 1
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
AUTO PAN
GATE
THRESHOLD
56
7
8
9
10
4
3
2
1
0
INT LFO1
OFF
WHITE
PINK
INT
LFO 1
OFF
GATE SEQ
MIDI
SYNC
CLOCK
2
56
7
8
9
10
4
3
1
0
GLIDE
2
56
7
8
9
10
4
3
1
0
OFF
GATE
CLOCK EG
AUTO
VCO 1
NOISE
AFT T
S&H
EG 2
LFO 1
VCO 2
LFO 2
VCO 3
SOURCE
MOD W
ENV FOLL
VCO 1
NOISE
AFT T
S&H
EG 2
LFO 1
VCO 2
LFO 2
VCO 3
SOURCE
MOD W
ENV FOLL
CVIN 12db
NOR
PHASE
REV
WAVEFORM
ENV FOLL
SHAPING SELECT
EG 1
EG 2
SEQ A+B
AFT T
SEQ A
SEQ B
HOLD
MOD W
S&H
LFO 2
ENV FOLL
LFO 2 SEQ A
MOD W
EG 1
S&HAFT T
KYBD
EG 2
SEQ A+B
SEQ B
LOW FREQUENCY OSCILLATOR 2
VCO PWM VCF 24db/12db
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
56
7
8
9
10
4
3
2
1
0
FREQUENCY WAVEFORM
ENV
FOLL
NGEG 1
EG 2
VCO 1 VCO 2 VCO3
S&H
EXT IN
SHAPING SELECT
AFT T
MOD W
HOLD
T
TUNING - MIDI
RTRGHOLD
MASTER TUNE
0+1
+2
+3
+4
-1
-2
-3
-4
5
b-5
+#
0+1
+2
+3
+4
-1
-2
-3
-4
TUNE 5
+#
5
b-
OCTAVE
64'
32'
16' 8' 4'
2'
WAVEFORM
0+1
+2
+3
+4
-1
-2
-3
-4
FINE 5
+#
5
b-
VOLTAGE CONTROLLED OSCILLATOR 1
OCTAVE
64'
32'
16' 8' 4'
2'
WAVEFORM
VOLTAGE CONTROLLED OSCILLATOR 2
LFO 1
2
56
7
8
9
10
4
3
1
0
AMT
2
56
7
8
9
10
4
3
1
0
VOLTAGE CONTROLLED OSCILLATOR 3
0+1
+2
+3
+4
-1
-2
-3
-4
TUNE 5
+#
5
b-
OCTAVE
64'
32'
16' 8' 4'
2'
0+1
+2
+3
+4
-1
-2
-3
-4
FINE 5
+#
5
b-AMT
2
56
7
8
9
10
4
3
1
0
LFO 1
2
56
7
8
9
10
4
3
1
0
WAVEFORM
AMT
2
56
7
8
9
10
4
3
1
0
LFO 1
2
56
7
8
9
10
4
3
1
0
SUB -2
SUB -1
LIN
EXP
SYNC VCO1
ON
KYBD
OFF
SUB -2
SUB -1
LIN
EXP
LIN
EXP
RM IN SEL
EXT IN
FM1 SOURCE
VCO 2
NOISE
VCO 3
EG 1
AFT T
LFO 1
LFO 2
S&H
VEL
EG 2
MOD W
PW
2
56
7
8
9
10
4
3
1
0
PWM
2
56
7
8
9
10
4
3
1
0
PWM
2
56
7
8
9
10
4
3
1
0
PW
2
56
7
8
9
10
4
3
1
0
LFO 1
LFO 2
56
7
8
9
10
4
3
2
1
0
PORTAMENTO BEND AMOUNT
56
7
8
9
10
4
3
2
1
0
ON
REV
NOR
SYNC VCO1
ON
PHASE
PHASE
REV
NOR
PHASE
VCO1 OFF
KYBD
OFF
MANUALPROGR
EDIT GATE ON
KYBD
OFF
MIDI ACT
VCO 3
REV
NOR
PW
2
56
7
8
9
10
4
3
1
0
PWM
2
56
7
8
9
10
4
3
1
0
LFO1
LFO 2
LFO1
LFO 2
+3
0+1
+2
+4
-1
-2
-3
-4
TUNE 5
+#
5
b-
0+1
+2
+3
+4
-1
-2
-3
-4
FINE 5
+#
5
b-
440Hz
56
7
8
9
10
4
3
2
1
0RANGE
MID
SLOW
FAST
VCA
56
7
8
9
10
4
3
2
1
0
RUN/STOP
SEQUENCER 8 x 2
56
7
8
9
10
4
3
2
1
0
X4
X2
QNT B
OFF
ON
QNT A
OFF
ON
RANGE A
X8
RANGE B
X4
X2
X8
GLIDE A
GLIDE B
16X1 8X2
MODE
56
7
8
9
10
4
3
2
1
0
STEP REPEAT
N,N,N+1,N
OFF
X2
X3 X4 N,N+1
N,N+1,N
CLOCK
OFF
RESETSTEP ADV
56
7
8
9
10
4
3
2
1
0
INT
LFO 1 EXT
CLOCK SELECT
A
1 2 3
PWM SEQ ENABLE
A+B
BB
FLT SEQ ENABLE
BB
AA+B
24db 12db
SEQUENCER MODE
FW
BW
FW/BW
PNDL
ALT
RND
TRG
56
7
8
9
10
4
3
2
1
0PW
123
VCO SEQ ENABLECV SEQ CLOCK
HOLD
OFF ON
LOOP
OFF ON
OFF OFF
A
B
LEVEL LEVEL
TIME
SEND MODULATION
NOISE
INPUT SOURCE
VCO 2
VCO 1
LFO 1
LFO 2
EXT IN
OVERLOAD
FREQUENCY
56
7
8
9
10
4
3
2
1
0
GATE
CLOCK / TRNP SEQ
B
A
GATE
ON
GATE
ON
END STEP
01
SKIP
NOR
GATE END STEP
ON SKIP
NOR
GATE END STEP
ON
03
SKIP
NOR
GATE END STEP
ON
04
SKIP
NOR
GATE END STEP
ON
05
SKIP
NOR
GATE END STEP
ON
06
SKIP
NOR
GATE END STEP
ON
07
SKIP
NOR
GATE END STEP
ON
08
SKIP
NOR
END STEP
09
SKIP
NOR
GATE END STEP
ON
10
b#
SKIP
NOR
GATE END STEP
ON
11
SKIP
NOR
GATE END STEP
ON
12
SKIP
NOR
GATE END STEP
ON
13
SKIP
NOR
GATE END STEP
ON
14
SKIP
NOR
GATE END STEP
ON
15
SKIP
NOR
GATE END STEP
ON
16
SKIP
NOR
#
00 0 0
0
0
0
0
0
0
bb#
0
02
b#b#b#
0
b#b#
0
b#
0
b#
0
b#b#
0
b#
0
b#b#b#
CLOCK DIVIDER
/3
/2
/1
1/1
/4
1/2T
1/2
/6
/8
1/4T
1/81/4
/12
1/8T
/16
/32
MONO
FM1 SOURCE
VCO 1
NOISE
VCO 3
EG 1
AFT T
LFO 1
LFO 2
S&H
VEL
EG 2
MOD W
FM1 SOURCE
VCO 1
NOISE
VCO 2
EG 1
AFT T
LFO 1
LFO 2
S&H
VEL
EG 2
MOD W
FLT
VCO 3
MAIN
CVIN VCA/AFTT
MIDI
GATEOUT 0/+5V
1/16
1/32
ROWA+ BTRNP
MIDI
BA+B
AA
!
!
!

Grp A4 Synthesizer – Owner’s Manual
!
!"

Grp A4 Synthesizer – Owner’s Manual
!
#"
CONTENTS!
"
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"
31'(')"0+-15,6"0(-("
" 417"0+-15,"0(-("('3,&*%2,"
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"
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"
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" 417"0+-15,"9!"=7"43%3,"8%&(%75,"*(53,&"
" 417"0+-15,",'8,5+.,"),',&%3+&"9"
"
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" 417"0+-15,",'8,5+.,"),',&%3+&"!"
"
0+-15,"%13+".%'"
"
0+-15,"43,&,+"0%('"
"
0+-15,"82"5+$"*&,>1,'2?"+42(55%3+&"9"
"
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"
0+-15,"4%0.5,";"@+5-"
"
0+-15,",<3"('"6",'8"*+55"
"
0+-15,"43,."4,>1,'2,&"AB!"
" 43,.".%&%0,3,&4"
" &+$"%";"7".%&%0,3,&4"
" &+$"%";"7"&+13(')4"
"4,>1,'2,&".%&%0,3,&4"
"
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"
&,%&".%',5"2+'',23(+'4"
!
!

Grp A4 Synthesizer – Owner’s Manual
!
/"
!"#$%&%'()*+),+#)*,)&-('.+
+
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"#!$%&&'('!"'((%))*+
+&!,-.',!/-0/-&-()')*1-!%2!3'(*2'4)5/-/+/&0+1.*'2"1(3"&+++
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+
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+
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#7N:M+/&0+%D+
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1Q*M!!&--!/-'/!0'(-,!,':-,!
+
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+
"
!
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^?57?I69:8:+:++
#69:8:+N5+#799:8I57<+%K@785@_+!7T6?6;5<+'85SK?6;5!
!

Grp A4 Synthesizer – Owner’s Manual
!
C"
Warranty
F=-! .5'/'()--! )-/3&! ,*&)-6! *(! 25,,! *(! )=-! 05/4='&-! './--3-()#! '/-! 1',*6! %(,E! *2! )=-! &E()=-&*>-/! *&!
5&-6!*(!)=-!4%(6*)*%(&!%2!*()-(6-6!5&-@!
F=-!%(,E!-G4-0)*%(&!)%!)=-!3'*()-('(4-!6-&4/*:-6!*(!)=-!4='0)-/@!H+"IFJI+IAJ!'(6!0-/2%/3-6!
K*)=! )=-! 0/%4-65/-&#! '(E! /-0'*/&! %/! 3%6*2*4')*%(&! )%! )=-! 35&*4',! *(&)/53-()! %/! 4%30'(*-&! (%)!
'5)=%/*>-6!:E!)=-!5&-/!6-)-/3*(-&!)=-!6-4'E!%2!)=-!K'//'()E@!
F=-! K'//'()E! 6%-&! (%)! -G)-(6! )%! 6'3'.-! 4'5&-6! :E! 3',0/'4)*4-! %/! (-.,*.-(4-! *(! )=-! 5&-! %2! )=-!
&E()=-&*>-/#!%/!:E!0%%/!3'*()-('(4-!%/!2'*,5/-@!
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F=-!0/%654)&!K-!&-,,!'/-!4%1-/-6!:E!K'//'()E!'&!)%!)=-!&E()=-&*>-/!)%!)=-!2%,,%K*(.!4%(6*)*%(&9!
L!
F=-!K'//'()E!*&!1',*6!2%/!'!0-/*%6!%2!M!N)K%O!E-'/&@!
M!
LO F=-! 3'(52'4)5/-/! 5(6-/)'P-&! )%! /-0,'4-#! ')! *)&! 6*&4/-)*%(! 0'/)&! 3',25(4)*%(*(.! %/! *(4%//-4),E!
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SO F=-! 3'(52'4)5/-/! '&&53-&! (%! /-&0%(&*:*,*)E! 2%/! '(E! 6*22*45,)*-&! )=')! 3'E! '/*&-! *(! )=-! 5&-! %/!
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V!
DO +/-! -G4,56-6! 2/%3! )=-! K'//'()E! 4%1-/! 0'/)&! &5:W-4)! )%! K-'/#! &54=! '&! 4%((-4)%/&#!
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F=-! 3'(52'4)5/-/! *&! (%)! ,*':,-! 2%/! '(E! 6'3'.-! )%! 0-/&%(&#! '(*3',&! %/! 0/%0-/)E! /-&5,)*(.! 2/%3!
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*(2%^./0&E()=-&*>-/@*)!=))09RR=))09RRKKK@./0&E()=-&*>-/@*)!
!
!
!

Grp A4 Synthesizer – Owner’s Manual
!
D"
T5-!)%!)=-!4%()*(5%5&!-1%,5)*%(!%2!0/%654)&#!2-')5/-&!'(6!6-&*.(!%2!)=*&!3%6-,!3'E!
4='(.-!K*)=%5)!(%)*4-@!
!
ID Labels
F=-! Y$7! ZE()=-&*>-/! +S! *&! -_5*00-6! K*)=! '(! *6-()*2*4')*%(! 0,')-! %(! K=*4=! )=-E!
/-0%/)-6! )=-! *6-()*2*4')*%(! %2! )=-! 6-1*4-! '(6! )=-! 3'*(! )-4=(*4',! 6')'! /-,')*(.! )%!
0%K-/!&500,*-&@!
!
!
+
+
`%&*(*/a+
+
+
')+-%(*'%(*+'2"+(*'"/&('.+b),+%$$+#)-0)*"*'1+
!"4(#"+(1+"11"*'(%$+#)-0$.+
10"#(,(#%'()*1+$(1'"!+)*+'2"+$%c"$[+
+
!
!
!
+
+
!%*/"&+
+
+
%##"11+')+0&)'"#'"!+)&+0%&'1+),+'2"+#$)1"!+
/&0+1.*'2"1(3"&+%D+-^1'+c"+-%!"+)*$.+
,)&+)0"&%'()*1+%*!+-%(*'"*%*#"+)*$.+
%^'2)&(3"!+0"&1)**"$[+
+
!
!

Grp A4 Synthesizer – Owner’s Manual
!
E"
Operation
A%((-4)!)=-!0%K-/!4%/6!*()%!)=-!"JA!&%4P-)!%(!)=-!/-'/!0'(-,#!3'P*(.!&5/-!)=')!)=-!
1%,)'.-!'(6!2/-_5-(4E!4%//-&0%(6!)%!)=-!,':-,@!
"(&-/)!)=-!0,5.!*()%!)=-!K',,!%5),-)@!
F=-!0%K-/!;JT!%(!)=-!2/%()!0'(-,!*(6*4')-&!)=-!4%//-4)!25(4)*%(*(.!%2!*(6*1*65',!
&-4)*%(&!%2!)=-!7Z`@!
!
Handling and cleaning
F=-!Y$7!+S!6%-&!(%)!(--6!'(E!3'*()-('(4-!)%!)=-!*()-/(',!4*/45*)&@!
F%!4,-'(!)=-!4%()'*(-/!*&!&*30,E!'!4,-'(!4%))%(!4,%)=!'(6!&,*.=),E!6'30@!F=-!0'*()!*&!
/-&*&)'()! )%! (%/3',! 4,-'(*(.! 0/%654)&#! K*)=! )=-! -G4-0)*%(! %2! &)/%(.! &%,1-()&!
N:-(>-(-#!'4-)%(-#!6*,5-()&!*(!.-(-/',#!-)4@@O@!
Troubleshooting
a-/-!'/-!&%3-!0/%:,-3&!E%5!3*.=)!-(4%5()-/!K=*,-!5&*(.!)=-!Y$7!ZE()=-&*>-/!+S@!
Z%3-!4'&-&!'/-!-'&E!)%!&%,1-#!K=*,-!%)=-/&!/-_5*/-!)=-!*()-/1-()*%(!%2!&0-4*',*>-6!
0-/&%((-,!%/! )=-!3'(52'4)5/-/@!T%! (%)!=-&*)')-!)%!4%()'4)!5&! K*)=!'(E!_5-&)*%(&@!
b-!'/-!=-/-!)%.-)=-/!)%!&%,1-!-1-/E!0/%:,-3@!
c:O78:+ I7??:I@5?T+ @J:+ /&0+ %D<+ 96d:+ LK8:+ @J6@+ @J:+ U7;@6T:+ 6?N+ IK88:?@+
?:I:LL68]+@7+S:+I79A6@5S;:+R5@J+@J:+IJ686I@:85L@5IL+7O+@J:+N:U5I:[+
Y$7! ZE()=-&*>-/! 6*&4,'*3&! '(E! ,*':*,*)E! 2%/! 3*&5&-! %2! )=-! Y$7! ZE()=-&*>-/!
&E()=-&*>-/!+S@+
!'J:+/&0+%D+N7:L+?7@+I79:+7?+X6;;+$"!L+68:+7OOY[+A=-4P!2%/!'(E!(-)K%/P!
*(! )=-! &%4P-)@! A=-4P! )=-! 0%K-/! 4%/6@! A=-4P! )=-! 25&-! *(&-/)-6! *()%! )=-! "JA!
&%4P-)! %(! )=-! /-'/! 0'(-,@! "2! )=-! Y$7! +S! &)*,,! 6%-&! (%)! ,*.=)#! 4%()'4)! Y$7!
ZE()=-&*>-/@!
!)?:+78+978:+$"!L+7?+@J:+O87?@+N7:L+?7@+;5TJ@+KA+6?N+@J:+L]?@J+N7:L?e@+
L7K?NL[!A%()'4)!Y$7!ZE()=-&*>-/@!
Fuse change
F=-!%(,E!5&-/c'44-&&*:,-!25&-!*&!4%()'*(-6!*(!)=-!'00/%0/*')-!0,'4-!*(!25&-!=%,6-/&!
"JA!0%K-/!&%4P-)!%(!)=-!/-'/!0'(-,@!F%!/-0,'4-#!2*/&)!6*&4%((-4)!)=-!0%K-/!4%/6#!
)=-(!/-3%1-!)=-!25&-!=%,6-/!5&*(.!'!&4/-K6/*1-/@!
!
+
+
`%&*(*/+
+
+
#2%*/"+'2"+"f'"&*%$+,^1"+)*$.+`('2+%*)'2"&+),+'2"++
1%-"+'.0"<+#^&&"*'<+!(-"*1()*+%*!+c"2%4()&[+(,<++
%,'"&+%+,(&1'+1^c1'('^'()*<+,^1"+c$)`1+%/%(*<+!)+*)'+%''"-0'+
%+1"#)*!+1^c1'('^'()*g+(*1'"%!<+!(1#)**"#'+'2"+1.*'2"1(3"&+
,&)-+%#+0)`"&+%*!+#)*'%#'+/&0+1.*'2"1(3"&[+
+
+
!
!
!

Grp A4 Synthesizer – Owner’s Manual
!
A"
!
+
+
!%*/"&+
+
+
*"4"&+%''"-0'+')+#2%*/"+,^1"+`('2+!"4(#"+#)**"#'"!++
')+%#+0)`"&+$(*"+
+
+
Important safety warnings
F=-! -(1*/%(3-()',! 0%,*4E! %2! Y$7! ZE()=-&*>-/! ,*3*)&! )%! )=-! 3*(*353! )=-! 5&-! %2!
0%,,5)*(.! 3')-/*',&! N,-'6#! &%,1-()&#! -)4@@O@! `(6-/! 45//-()! ,-.*&,')*%(#! E%5! 35&)!
6*&0%&-!%2!)=-!Y$7!ZE()=-&*>-/!+S!*(!'44%/6'(4-!K*)=!,%4',!/-.5,')*%(&!/-.'/6*(.!
6*&0%&',! %2! K'&)-! -,-4)/*4',! '(6! -,-4)/%(*4! -_5*03-()@! [%/! (%! /-'&%(! )%! ':'(6%(!
)=-! 0/%654)! *(! )=-! -(1*/%(3-()9! '4)*%(#! )=*&#! '! 4/*3*(',! %22-(&-#! '(6! '! &%5/4-! %2!
,%(.!)-/3!0%,,5)*%(@!
"(!%/6-/!(%)!)%!*(45/!)=-!/*&P!%2!-,-4)/*4!&=%4P!'(6!R!%/!*(W5/*-&!E%5!35&)!4'/-25,,E!
2%,,%K!)=-!*(&)/54)*%(&!*(!)=-!3'(5',!'(6!*(!)=-!(%)-&!:-,%K@!
+
+
`%&*(*/+
+
+
')+%4)(!+&(1h+),+"$"#'&(#+12)#h+
%*!+Q+)&+(*\^&.+.)^+-^1'+,)$$)`+
'2"+(*1'&^#'()*1+(*+'2"+-%*^%$+%*!+'2"+*)'"1+c"$)`[+
+
!
F!7+ ?7@+ 7A:?+ @J:+ L]?@J:L5B:8g+ ?:U:8+ 7A:?+ 5@[+ 'J:+ 8:97U6;+ 78+
N5L6LL:9S;]+ 7O+ 6?]+ A6?:;+ 5?U7;U:L+ @J:+ 7A:86@78+ :iA7LK8:+ @7+
A7@:?@56;;]+ J6B68N7KL+ U7;@6T:L[+ ,78+ R78d5?T+ 5?L5N:<+ /&0+ 1]?@J:L5B:8+
6?N+ I7?@6I@+ 7?;]+ jK6;5O5:N+ A:8L7??:;[*7?+ 859K7U:8:+ 6;IK?6+ U5@:+ LK5+
A6??:;;5+:L@:8?5+N:;;e6AA686@7[+
Fk+ !7+ ?7@+ :iA7L:+ @J5L+ 6AA686@KL+ @7+ 865?<+ R6@:8+ LA86]<+ :iI:LL5U:+
975L@K8:<+ U6A78<+ NKL@<+ 9:@6;+ A68@5I;:L+ 78+ 6?]+ 7@J:8+ 96@:856;+ @J6@+ I6?+
A:?:@86@:+5?@7+@J:+U:?@5;6@57?+J7;:L[+
F!7+?7@+AK@+ 7@J:8+7Sl:I@L+5?+ @J:+%#+ A;KT+ 7?+@J:+ 8:68+ A6?:;<+:iI:A@+ @J:+
6AA87A856@:+A7R:8+I6S;:[+
F!7+?7@+:iA7L:+@J5L+6AA;56?I:+@7+J:6@[+
F!7+ ?7@+ :iA7L:+ @J:+ K?5@+ @7+ :iI:LL5U:+ LJ7Id+ 78+ U5S86@57?+ NK85?T+
7A:86@57?[+
Fk+ `J:?+ 5?L@6;;5?T<+ 78+ KL5?T+ 5?+ @J:+ ;7I6;+ J7@+ 6?N+ JK95N+ 6L+ 6+ 8:LK;@+ 7O+
L@786T:+ 78+ @86?LA78@+ 6@+ U:8]+ ;7R+ @:9A:86@K8:L<+ 5@+ 5L+ A7LL5S;:+ @J:+
O7896@57?+ 7O+ I7?N:?L6@57?+ 7?+ @J:+ 7K@L5N:+ 6?N+ 5?L5N:+ @J:+ N:U5I:[+ (@+ 5L+
@J:8:O78:+ ?:I:LL68]+ @7+ R65@+ O78+ @J:+ I7?N:?L6@57?+ N5L6AA:68L+ S:O78:+
@K8?5?T+]7K8+K?5@[+

Grp A4 Synthesizer – Owner’s Manual
!
G"
F%;R6]L+KL:+@J:+A87A:8+6?N+K?N696T:N+A7R:8+I6S;:L[+"LA:I56;;]<+?:U:8++
S8:6d+@J:+I:?@:8+I7?NKI@78+7O+@J:+A5?L+78+L7Id:@L+I7??:I@5?T+@7+:68@J+
@J:+A87@:I@5U:+9:@6;+I6L5?T[+
Fk+%;R6]L+IJ:Id+@J6@+@J:+965?L+A7R:8+5L+I7?L5L@:?@+R5@J+@J6@+8:A78@:N+
5?+@J:+S6Id+7O+@J:+N:U5I:[+
Fk+!7+?7@+7SL@8KI@+@J:+U:?@5;6@57?+J7;:L+7O+@J:+K?5@[+
F(?+ I6L:+ 7O+ L:U:8:+ @JK?N:8L@789L<+ 6U75N+ KL5?T+ @J:+ N:U5I:+ 6?N+
N5LI7??:I@+5@+O879+965?L+6?N+7@J:8+:jK5A9:?@[+
F(O+ @J:+ OKL:+ 5L+ ?7@+ 6+ 8:LK;@+ 7O+ :i@8678N5?68]+ :i@:8?6;+ :U:?@L<+ LKIJ+ 6L+
LKNN:?+ 78+ U57;:?@+ ?:@R78d+ 7K@6T:L<+ L@789L+ :@I[[<+ N7+ ?7@+ @8]+
8:A;6I:9:?@<+SK@+N7+IJ:Id+@J:+K?5@+S]+6+jK6;5O5:N+@:IJ?5I56?[+
F!7+?7@+O78I:+@J:+8K?+7O+@J:+8:TK;6@57?L+S:]7?N+@J:+;595@L[++
!
Notes
!
!
!

Grp A4 Synthesizer – Owner’s Manual
!
9H"
!
FOREWORD!
Thank you for purchasing the Grp Synthesizer A4: this machine will rewards you with
years of sonic satisfactions and, to ensure your instrument will functions properly,
please read this manual.
SOME!WORDS!OF!WISDOM!
Read the following safely tips carefully! You should always observe some basic
precautions when dealing with electronic equipment, for you safety and for safety of
your own equipment.
OPERATING!CONDITIONS!
•Never use the synthesizer under potentially damp/wet conditions such
bathrooms, swimming pools, etc.
•Do not use the instrument in extremely dusty and dirty environments.
•Do not place the instrument near heat sources like radiators.
•Do not expose the instrument to direct sunlight; the wooden cabinet is
varnished with a traditional and trusted procedure, but ultraviolet rays from
sunlight can quickly fade the original wooden colour.
•Do not expose the device to extreme vibrations.
•Save the original crate and boxing for future shipping of the instrument.
POWER!SUPPLY!
•Your Grp A4 Synthesizer is already set for the correct AC powering for your
area. You can read it on the label in the rear panel.
•Unplug the device when you are not using it for longer periods.
•Never touch the plug with wet hands.
•When unplugging the instrument, always grab and pull the plug, never the cable.
OPERATION!
•Although you are a rockstar, NEVER place cans of beer, coke, water (?) or
other potentially spilling liquids on or near the instrument.
•The Grp A4 Synthesizer is an heavy synthesizer: place it on a suitable solid
surface or table.
•The Grp A4 Synthesizer can be very LOUD: please, be careful with the big
volume knob on the lower right of the front panel.
MAINTENANCE!
•Do not open the instrument; do not unscrew the front/rear panels. Inside the
instrument, there aren’t user’s serviciable parts.
PROPER!USE!
•This synthesizer is designed exclusively to produce audio rate frequency signals
for musical purpose. Any other use is prohibited and voids the warranty
extended by Grp Synthesizer. Grp Synthesizer is non liable for damanges due
to incorrect use.