Mackie SP1200 Stereo Amplifier User Manual


 
SP1200 11
CAUTION: When using multiple SP1200s
that use the expansion bus, these switch
settings
must
be unique to each unit or
you can damage your SP1200(s). Never assign
more than one program source to the same channel
on the Expansion Bus.
If there is a requirement for music-on-hold, use
Input 1 for the continuous music source (i.e.,
satellite feed, prerecorded background music, multi-
disc CD player). Then use the
DIRECT OUTPUT
jacks to route the signal to the telephone system.
If there is a jukebox or other device that needs
priority, use Input 4 in Program Priority mode (set
the
AMP ADDRESS
switch #7 UP to activate).
When a signal appears at Input 4 it overrides the
selected Input source.
Using a chart similar to the one below can be
very helpful in organizing the various components
of the system:
Zone
Source
SAT
CD
Cassette
Tuner
Jukebox
AXXXXX
XXXXX
XX X
XX X
XXX
XXX X
XX X
B
C
D
E
F
G
3.
Is there a paging microphone? Is there a
requirement for a local microphone for a guest
speaker?
You must decide where the microphones
are going to be located. Avoid placing a microphone
near a speaker, to increase gain before feedback. If
the mics require phantom power, set the
PHANTOM
power switches to the down position (ON) for the
Paging Mic and Mic/Line Inputs. Make sure the
GAIN +40 dB
switch is set to the down position as
well (+40).
Note: The Paging Mic has priority over the system,
including Input 4.
4.
Is there a manual switch for paging?
Up to
two switches can be connected to the SP1200
PAGING MIC CONTROL
to manually engage the
paging microphone. Otherwise, the paging mic can
be voice-activated. Adjust the
VOX
control as
described on page 19.
Connections
Connecting the Program Sources
All four Program Inputs use unbalanced RCA
connectors. They accept line-level signals (10
dBV). Each of the Program Inputs is equipped with
an AGC circuit instead of input trim controls. These
circuits automatically adjust the gain for the best
signal-to-noise ratio according to the strength of the
input signal. It also ensures that the relative volume
level remains the same when switching between
input sources.
Use high-quality, two-conductor shielded cable
to make these connections.
Connecting the Microphones
If using the XLR input for the paging microphone,
wire it per AES standard where pin 1 is ground
(shield), pin 2 is signal high (+), and pin 3 is signal
low (). If using the Phoenix-type connector, strip
the wire back about 1/4" inch. Then insert the wire
as far as it will go into the appropriate hole in the
connector, and tighten down the screw with a small
slot-head screwdriver. It is recommended that you
use 20 or 22 gauge wire with the Phoenix-type
connectors, where pin 1 (the left-most pin) is
ground (shield), pin 2 is signal high (+), and pin 3 is
signal low ().
The
MIC/LINE INPUT A is
for a local microphone.
This is a Phoenix-type connector, and is wired as
described in the previous paragraph for the paging
microphone.
All microphone inputs are equipped with a pad
switch for use with line-level signals. When connect-
ing a line-level signal to these inputs, make sure the
GAIN +40 dB switches (and the PHANTOM
switches) are in the up (OFF) position.
Connecting the Speakers
The speaker output connector is a two-
conductor Phoenix-type, with a position-locking
mechanism. Use 16 or 18 gauge wire for connecting
the amplifier outputs to the speakers. If the amplifier
output is configured for 8-ohm operation, connect
the speakers' output directly to an 8-ohm load. The
amplifier will deliver up to 200 watts. If the amplifier
is configured for either 70V or 100V operation,
connect the speaker output directly to the
distributed system. No output transformer is
required. Make sure that the taps on the speakers
add up to 200 watts or less per amplifier for 70V or
100V systems.