Balanced operation – Simaudio 740P Preamplifier User Manual
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740P Dual-Mono Preamplifier
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Figure 5: Remote Operation with 12V Trigger
In figure 4 we have a 740P Preamplifier and 860A
amplifier connected together via their respective 12V
triggers; The 12V trigger output on the 740P is
connected to the 12V trigger input on the 860A
(using a 1/8” mini-jack cable). When you turn on the
740P via remote control (or its Standby button), the
860A will turn on automatically. The same rule
applies when you put the 740P into Standby mode.
Balanced Operation
When using an unbalanced interconnect, the audio
signal runs through both the center wire and the
shield/ground wire. Any noise picked up by this
interconnect (ie. nearby magnetic fields such as an
AC power cord) will be reproduced by the integrated
amplifier, then heard through the loudspeakers.
Conversely, a balanced interconnect has three
separate conductors; one for the ground and two for
the actual signal. These two signals are identical
except that one is 180 degrees out of phase with the
other. For example, when one conductor is carrying
a signal of +10 Volts, the other will be carrying a
signal of –10 Volts. When these two inverted
signals on a balanced line are output from the
MOON 740P, any noise picked up by the
interconnect will be eliminated since a differential
circuit amplifies only the difference between these
two signals: Noise on a balanced interconnect will be
equal on both conductors and therefore cancel out.