Input Connection; Unbalanced Input Wiring For The Optional Mt-Xlr; Balanced Input Wiring For The Optional Mt-Xlr; Balanced And Unbalanced Phone Plug Wiring - Crown Micro-Tech 600 Reference Manual

3.3.4 Input Connection

The balanced phone jack inputs have a nominal im-
pedance of 20 K ohms (10 K ohms with unbalanced
wiring) and will accept the line-level output of most de-
vices. Three-pin female XLR connectors are also avail-
able on the optional MT-XLR accessory and balanced
barrier block connectors are available on the optional
MT-BB accessory (see Section 8.2). Correct input wir-
ing will depend on two factors: (1) whether the input
signals are balanced or unbalanced, and (2) whether
the signal source floats or has a ground reference. Fig-
ures 3.7 and 3.8 provide examples of recommended
connection techniques for each type of signal source.
The optional MT-XLR connector is shown.
Shield connected
Floating
to ground terminal
source
Output
+
2-wire line cord
(or battery power)
Shield is not
Grounded
connected
source
at this end
+
Output
3-wire grounded line cord
(or other ground connection)
Floating
Shield connected to both
source
negative (–) and ground
input terminals
Output
+
2-wire line cord
(or battery power)
Grounded
Input ground
source
terminal not used
+
Output
3-wire grounded line cord
(or other ground connection)
Fig. 3.7 Unbalanced Input Wiring
for the Optional MT-XLR
Page 14
+
–
3
INPUT
1 2
– +
3
INPUT
1 2
+
–
3
INPUT
1 2
+
–
3
INPUT
1 2
Micro-Tech 600/1200/2400 Power Amplifiers
Note: If two or more channels with
the same input ground reference
are driven from the same
floating source, connect
Floating only one shield to the
source chassis.
source
–
Output
+
2-wire line cord
(or battery power)
Grounded
Shield not connected
source
at this end
Output
–
+
3-wire grounded line cord
(or other ground connection)
Fig. 3.8 Balanced Input Wiring
for the Optional MT-XLR
The amplifier's built-in 1 ¦
4
can be wired similarly for balanced or unbalanced,
floating or ground-referenced sources. The phone con-
nectors have a standard tip-ring-sleeve (TRS) configu-
ration: the tip is positive (+), ring is negative (–) and
sleeve is ground (see Figure 3.9). Wiring for different
sources follows the XLR wiring guidelines shown in Fig-
ures 3.7 and 3.8.
When either of the input connector accessories is in-
stalled, the unused input connectors can be used as
"daisy chain" outputs to feed the input signal from one
amplifier to another.
Please follow the input wiring instructions in Section
3.3.2 and 3.3.3 if the amplifier will be used in either
Bridge-Mono or Parallel-Mono mode. Remember, do
not use the channel 2 input in either mono mode.
Fig. 3.9 Balanced and Unbalanced
Phone Plug Wiring
+
–
3
INPUT
1 2
– +
3
INPUT
1 2
-inch input phone connectors
+
BALANCED
–
SHIELD
+
UNBALANCED
SHIELD