Bridge / Stereo / Parallel switch
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Output connectors
Input connectors
Channel Input control
Protection LED
Three-segment LED meter
Setting Up and Using Your SX Series
Setting up your SX Series is a simple procedure which takes only a few minutes:
1. Remove all packing materials (save them in case of need for future service) and decide where the
amplifier is to be physically placed—it can be used free-standing or mounted in a standard 19" rack,
requiring only two rack spaces. When installed, make sure that both the front and rear panels are
unobstructed and that there is good ventilation around the entire unit (we recommend the use of
spacer panels, especially if multiple amplifiers are used in a rack.
2. Set the rear panel Bridge/ Stereo / Parallel switch as desired (see the "Bridge and Parallel Modes"
section on page 8 in this manual for more information).
3. Make the speaker connections, using the banana, or Speakon™ output connectors on the rear
panel. It is never a good idea to power up any amplifier that is not connected to loudspeakers.
When operating in Stereo or Parallel mode, any loudspeakers with a minimum impedance load of 4
ohms (that is, 4 ohms or greater) can be used; however, in Bridge mode, 8 or 16 ohm speakers must
be used. Be sure to connect the loudspeaker correctly. In Stereo or Parallel mode, make sure the
red (+) terminal is connected to the positive input of the speaker and the black (ground) terminal
is connected to the negative input of the speaker. See page 8 in this manual for more information
about Bridge mode and pages 9 - 10 in this manual for full speaker interconnection instructions.
4. Next, make the signal input connections, using the Combination input connectors on the rear
panel (if operating the SX Series in Bridge or Parallel mode, use the Channel 1 input only—see page
8 in this manual for more information). If your mixer or crossover network has balanced outputs, we
recommend the use of three-conductor cabling and connectors (unbalanced two-conductor plugs
can also be inserted into the Combo inputs, but you'll get better signal quality and less outside
noise and hum if you use balanced lines).
5. On the front panel of the SX Series, turn both Channel input controls fully counterclockwise (to
their "MIN" setting). Then connect the supplied heavy-gauge 3-pin "IEC" cable to the rear panel IEC
connector and to any grounded AC socket.
Because of the relay protection circuitry built into the SX Series, you can even plug it into the same
power strip that other audio devices (such as a mixing console) are connected to. You can then turn
on all devices at once with the single power strip on-off switch, with no danger of damaging con-
nected speakers by generating "thumps. "
6. Press the front panel Power switch in order to turn on the SX Series. The Power LED will light
and the Protection LED will go on. After approximately five seconds, the Protection LED will go off
(you'll hear a click when this occurs).
7. Apply an input signal to the SX Series at or about +4dBu (if sending signal from a mixer, drive the
output meters at approximately 0 vu). While the input signal is present, slowly raise the Channel
Input controls until the desired sound level is achieved. The SIGNAL and PEAK LED indicators next
to each Channel input control will show you the continuous power output of the SX Series as signal
is being passed. For the best signal-to-noise ratio, the SX Series should normally be run with the
Channel Input controls at or near maximum (fully clockwise, at the "MAX" position) and the PEAK
segments should light occasionally (but not frequently) during peak levels. If you are using a mixer
that has a master output level control (sometimes called "control room level"), use it to attenuate
the signal as necessary to achieve the desired speaker level.
NOTE: If you are operating the SX amplifier at high power levels for long durations in fixed installations,
you may consider switching the operating voltage to 220 volts. A licensed and insured electrician and/or
technician should perform this modification.
If you encounter difficulty with any aspect of setting up or using your SX Series, contact your local
Samson dealer. If purchased in the United States, you can call Samson Technical Support (1-800-
372-6766) between 9 AM and 5 PM EST.
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