Input Connection; Unbalanced Input Wiring; Balanced And Unbalanced Phone Plugs - Crown STUDIO AMPLIFIER Owner's Manual

3.3.4 Input Connection

The balanced inputs have a nominal impedance of
10 K ohms (5 K ohms unbalanced) and will accept the
line-level output of most devices. Phone jacks are pro-
vided on the back panel, while the factory-installed
P.I.P.-FX provides female XLR input connectors (see
Figure 2.2). Optional P.I.P. modules like the P.I.P.-BB
and the P.I.P.-FPX can provide barrier block and
phono (RCA) connectors. Various P.I.P.s are also avail-
able which provide a wide range of input signal pro-
cessing features (see Section 8).
Correct input wiring depends on two factors:
(1) whether the input signal is balanced or unbal-
anced, and (2) whether the signal floats or has a
ground reference. Figures 3.8 and 3.9 show the recom-
mended connection techniques for each combination
of source signal characteristics.
Floating
source
Output
2-wire line cord
(or battery power)
Grounded
source
Output
3-wire grounded line cord
(or other ground connection)
Floating
source
Output
2-wire line cord
(or battery power)
Grounded
source
Output
3-wire grounded line cord
(or other ground connection)
Fig. 3.8 Unbalanced Input Wiring
I I I I I II II II II II
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
source
Output
3-wire grounded line cord
(or other ground connection)
Fig. 3.9 Balanced Input Wiring
The amplifier's built-in 1 ¦
be wired similarly for balanced or unbalanced, floating
or ground-referenced sources. They have a standard
tip-ring-sleeve (TRS) configuration: the tip is positive
(+), the ring is negative (–) and the sleeve is ground
(see Figure 3.10). Wiring for various sources follows
the XLR wiring examples in Figures 3.8 and 3.9.
If you install a P.I.P. module other than the P.I.P.-FX,
P.I.P.-BB, P.I.P.-FMX or P.I.P.-FPX, do not connect in-
put signals to the phone jacks. The phone jacks are in
parallel with the output of the P.I.P. module, so the
source connected to the phone jacks can feed into the
P.I.P. and generate a distortion in the output. The
phone jacks can still be used as "daisy chain" outputs
to feed the post-processed signal from the P.I.P. to the
input of other amplifiers.
If the amplifier will be used in Bridge-Mono or Parallel-
Mono mode, be sure to follow the instructions provided
in Sections 3.3.2 and 3.3.3. Do not use the channel 2
input in either mono mode.
Fig. 3.10 Balanced and Unbalanced Phone Plugs
Professional Studio Amplifiers
-inch input phone jacks can
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