Bridge And Parallel Modes - Samson Audio SX1200 Mode D'emploi

Bridge Mode
INPUT
CHANNEL
1(+) OUTPUT
CHANNEL
2(+) OUTPUT
The SX Series provides a rear-panel switch that allows it to be used in either a Bridge
or Parallel mode. When this switch is placed in the "STEREO" (center) position, the SX
Series functions as a true stereo amplifier, where both of the two independent ampli-
fier channels (Channel 1 and Channel 2) can receive different input signals and pro-
duce independent output signals. However, when the switch is placed in the "Bridge"
(left) position, the Channel 1 inputs signal is routed to both power amplifiers bridged
together, producing a single output signal with 900 watts for the SX1200, 1200 watts
for the SX1800, 1500 watts for the SX2400, 1800 watts for the SX2800 and a massive
2200 watts for the SX3200 into 8 ohms load.
WARNING: Bridge mode is to be used only when the SX Series is connected to an
8 or16 ohm speaker load. Use of Bridge mode with speaker loads of less than 8
ohms can result in severe damage to the unit due to excessive heat and current
limiting and will void your warranty!
The illustration on the right shows how this works. In Bridge mode, the polarity
(phase) of the Channel 2 output signal is reversed relative to that of the Channel 1 out-
put signal. Both channels then process the same input signal, with the speaker load
connected so that power is derived from both channels. The effective voltage swing
seen by the load is thus doubled, so that the power output is multiplied by more four.
When using the SX Series in Bridge mode, be sure to connect your loudspeaker as
shown in the illustrations on page 9 (and as silkscreened on the rear panel), with the
red (+) terminal of the Channel 1 output connected to the positive input of the speak-
er and the red (+) terminal of the Channel 2 output connected to the negative input of
the speaker.
Do not use the black ground (-) output terminal of either channel (the speaker
load must "float" away from the amplifier chassis).
When the rear panel switch is placed in the right "PARALLEL" position, the SX Series
operates in a unique Parallel mode. In this mode, only the signal present at the
Channel 1 input is used. This signal is then routed to both the Channel 1 and Channel
2 power amplifiers, thus producing a dual mono output, with the following power rat-
ings:
SX1200 2 x 300 Watts at 8Ω and 2 x 450 Watts at 4Ω
SX1800 2 x 400 Watts at 8Ω and 2 x 600 Watts at 4Ω
SX2400 2 x 550 Watts at 8Ω and 2 x 750 Watts at 4Ω
SX2800 2 x 700 Watts at 8Ω and 2 x 900 Watts at 4Ω
SX3200 2 x 800 Watts at 8Ω and 2 x 1100 Watts at 4Ω
See pages 9 - 10 in this manual for interconnection diagrams when using the SX
Series in Bridge or Parallel modes.
9

Bridge and Parallel Modes