17
Cable connection
• Connect INPUT of the amplifier to the head unit line output with good quality RCA cables.
By connecting the RCA jacks OUTPUT with a additional amplifier, a full range signal will be
provided to the amplifier.
• Connect the subwoofer with the terminal block (SPEAKER BRIDGED -) of the
amplifier.
• The minimum final subwoofer impedance must not be below 4 Ohm per channel pair. Too low
speaker loads result in too high heat dissipation and may cause the amplifier run into
protection.
• Please observe speaker channel and polarity as printed by the speaker terminal block.
Incorrect phasing of the speakers results in total loss of bass response.
•
•
•
•
X-OVER - Switch & Control
• For the operation with one subwoofer select at X-OVER "LP/BP" (LOW PASS/BANDPASS).
Adjust a frequency between 30Hz - 150Hz, depending on the size and response of the Subwoofer.
The Lowpass adjustment can be done with the LOW PASS control.
• The HIGH PASS - Control is working in this configuration as controller to adjust the Subsonic-Frequency (lower Frequency Cut-off).
Therewith a BANDPASS-Signal will be generated, where too low and not hearable frequencies will be eliminated.
Thereby a clean and powerful Bass-Signal will be generated. The adjustable level depends on the size and response of the
subwoofer and should be between 10Hz (no cut-off) and 30Hz (max. suggested Level).
NOTE: If the HIGH PASS - Level is higher than the LOW PASS - Level, no Sound is hearable.
LEVEL INPUT - Control
• Turn the LEVEL INPUT - Control on the amplifier to "4V" position.
• Turn the head unit volume control to about 80-90% of its full setting.
• Turn the LEVEL INPUT - Control clockwise until you hear some distortion.
• Then turn back the LEVEL INPUT - Control slightly until you can hear clean sound.
BASS BOOST - Control
• The BASS BOOST - Control adjusts the bass level at 45 Hz from 0 up to 12dB. Please use the Bass-Boost carefully.
BASS REMOTE
• The BASS REMOTE allows to control the Bass-Level for example from the driver's seat.
1-Channel-Mode: 1 Subwoofer / Mono bridged
Caution
Please avoid to connect speaker (-) to the ground or vehicle chassis.
Connect RCA cable
from head-unit with
RCA input (INPUT).
Subwoofer
4 - 8 Ohm
FU
SE
BR
ID
GE
D
SP
EA
KE
R
OU
TP
UT
GN
D
RE
M
12
V
PO
W
ER
IN
PU
T
L
R
O
UT
PU
T
O
UT
PU
T
LL
RR
IN
PU
T
IN
PU
T
LL
RR
PO
W
ER
PO
W
ER
PR
OT
EC
T
PR
OT
EC
T
BA
SS
R
EM
OT
E
BA
SS
R
EM
OT
E
HPHP
LP
/BP
LP
/BP
FU
LL
FU
LL
X-O
VE
R
X-O
VE
R
BP
F
BP
F
4V4V
30H
z
30H
z1
50H
z
150
Hz
0d
B
0d
B
12d
B
12d
B
BA
SS
B O
OS
T
BA
SS
B O
OS
T
0.2
V
0.2
V
1.2
kH
z
1.2
kH
z
10H
z
10H
z
HIG
H P
AS
S
HIG
H P
AS
S
LO
W
P A
SS
LO
W
P A
SS
LE
VE
L I N
PU
T
LE
VE
L I N
PU
T
BASS REMOTE
2 Channel Amplifier - Speaker- & RCA-Connection
GTR420.2 – GTR620.2
