4 channel full range stereo, 2 or 3 channel system, Stereo line input mono line input – MB QUART REF4.50 User Manual
Page 6
4-Channel Amplifiers
REF4.50 / REF4.80
5
FEATURES:
- 2 Sets of RCA inputs
- LEVEL: Variable sensitivity from 0.2V to 6V
- BASS BOOST: Adjustable 45Hz bass boost from 0dB to 9dB
- Crossover functions
- FULL: Bypasses all crossovers for full frequency operation
- HIGH: Selects the built in HIGHPASS filter, variable from 15Hz to 250Hz
- CLONE (Ch3/4): Will automatically duplicate the settings on Ch3/4 for Ch1/2
- POWER LED: Indicates the powered up and turned on condition
- PROTECTION LED: Indicates a high voltage, low voltage, short circuit,
hard clip, over heating or DC fault condition.
- MODE: “2” indicates one set of RCA’s are being used. This will also pass signal to channels 3/4 through 1/2 inputs.
“3” indicates bridging channels 3/4 while running 1/2 in stereo. “4” indicates connecting 2 sets of RCA’s to 1/2 and
3/4 inputs.
- LINE OUTPUT: Full range RCA pass through.
4 Channel Full Range Stereo:
Control checklist:
Interconnect cable checklist:
- Refer to the section “Settings for Best Performance”
- Connect the four inputs of the amplifier to a Radio/CD with quality RCA cables.
Switch setting checklist:
Minimum final loudspeaker impedances:
- 1/2CH X-OVER: FULL
- 2 ohm per channel.
- 3/4CH X-OVER: FULL
MODE: “4” since 2 sets of RCA’s are connected.
2 or 3 Channel System:
- It is necessary to feed the SAME signal to both left and right inputs via a Y-adapter RCA cable.
Here we show how to use the 4 channel amplifiers as a 3 channel unit by taking
- Connect the mono speaker positive terminal to the Ch3 +, and its negative terminal to Ch4 - as
advantage of the mono bridging capability of all MB Quart amplifiers. In order to create
shown.
a 2 channel system, simply follow the example to also mono bridge channel pair 1/2.
Interconnect cable checklist:
Switch setting checklist:
- Connect the inputs of channel pair 1/2 to a suitable stereo source, e.g. a head unit
- 1/2CH X-OVER: FULL
with good quality RCA cables.
- 3/4CH X-OVER: LOW (LOW PASS)
- A MONO signal source is required to bridge channel pair 3/4, such as would be
Control checklist:
available from the mono sub bass output of an active crossover, whether standalone, or
- Refer to the section “Settings for Best Performance”
built into a head unit or equalizer.
Minimum final loudspeaker impedances:
Important: Do not be tempted to connect the hot, or positive outputs, from any source
- 2 ohm per channel in stereo mode.
together to obtain a mono signal, as this could very well damage the output stage of
- 4 ohm mono bridged.
that source.
O
U
T
Ch3
Ch1
Ch4
Ch2
IN
P
U
T
L
E
V
E
L
6V
0
.2
V
15
H
z
2
50
H
z
F
U
L
L
H
IG
H
C
L
O
N
E
F
U
L
L
H
IG
H
L
O
W
(C
h
3/4
)
H
IG
H
P
A
S
S
30
H
z
25
0H
z
L
O
W
P
A
S
S
6V
0
.2
V
L
E
V
E
L
0d
B
9d
B
B
A
S
S
B
O
O
S
T
15
H
z
25
0H
z
H
IG
H
P
A
S
S
P
O
W
E
R
P
R
O
T
E
C
T
IO
N
M
O
D
E
2
4
C
h
1/2
C
h
3/4
P
O
W
E
R
IN
P
U
T
G
N
D
R
E
M
B
A
T
T
+
12
V
S
P
E
A
K
E
R
O
U
T
P
U
T
C
h
1
C
h
2
C
h
3
C
h
4
-
+
-
+
-
+
-
+
B
R
ID
G
E
D
B
R
ID
G
E
D
S
P
E
A
K
E
R
O
U
T
P
U
T
C
h
1
C
h
2
C
h
3
C
h
4
-
+
-
+
-
+
-
+
B
R
ID
G
E
D
B
R
ID
G
E
D
F
U
S
E
O
U
T
Ch3
Ch1
Ch4
Ch2
IN
P
U
T
L
E
V
E
L
6V
0
.2
V
15
H
z
2
50
H
z
F
U
L
L
H
IG
H
C
L
O
N
E
F
U
L
L
H
IG
H
L
O
W
(C
h
3/4
)
H
IG
H
P
A
S
S
30
H
z
25
0H
z
L
O
W
P
A
S
S
6V
0
.2
V
L
E
V
E
L
0d
B
9d
B
B
A
S
S
B
O
O
S
T
15
H
z
25
0H
z
H
IG
H
P
A
S
S
P
O
W
E
R
P
R
O
T
E
C
T
IO
N
M
O
D
E
2
4
C
h
1/2
C
h
3/4
P
O
W
E
R
IN
P
U
T
G
N
D
R
E
M
B
A
T
T
+
12
V
F
U
S
E
STEREO LINE INPUT
MONO LINE INPUT
OUT
C
h
3
C
h
1
C
h
4
C
h
2
INPUT
LEVEL
6V 0.2V
15Hz 250Hz
FULL HIGH CLONE
FULL HIGH LOW
(Ch3/4)
HIGHPASS
30Hz 250Hz
LOWPASS
6V 0.2V
LEVEL
0dB 9dB
BASS
BOOST
15Hz 250Hz
HIGHPASS
POWER
PROTECTION
MODE
2
4
Ch1/2
Ch3/4