7
Bridged and Parallel Modes
The S1500 / S2000 provides a rear-panel switch that allows it to be used in
either a Bridged or Parallel mode. When this switch is placed in the “STEREO”
(center) position, the S1500 / S2000 functions as a true stereo amplifier, where
both of the two independent amplifier channels (Channel 1 and Channel 2) can
receive different input signals and produce independent output signals.
However, when the switch is placed in the “BRIDGED” (left) position, the
Channel 1 inputs signal is routed to both power amplifiers bridged together,
producing a single output signal with a true 1500 watt output into a single 8 ohm
channel (in the case of the S1500) or a true 2000 watt output into a single 8 ohm
channel (in the case of the S2000).
The illustration on the right shows how this works. In Bridged mode, the
polarity (phase) of the Channel 2 output signal is reversed relative to that of
the Channel 1 output 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 doubled.
When using the S1500 / S2000 in Bridged 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 2 output connected to
the negative input of the speaker and the red (+) terminal of the Channel 1
output connected to the positive 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
S1500 / S2000 operates in a unique Parallel mode. In this mode, only the signal
present at the Channel 1 input is used (and only the Channel 1 input control is
functional). This signal is then routed to both the Channel 1 and Channel 2
power amplifiers, thus producing a dual mono output, with 750 watts per channel
into 4 ohms (in the case of the S1500) or 1000 watts per channel into 4 ohms (in
the case of the S2000).
See pages 8 - 9 in this manual for interconnection diagrams when using the
S1500 / S2000 in Bridged or Parallel modes