Balanced operation – Simaudio 750D DAC User Manual
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750
D Reference DAC / CD Transport
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Figure 5: Remote Operation with SimLink™ and 12V Trigger
In figure 5 we have a 750D DAC connected to a
740P Preamplifier via their respective SimLink™
ports (using a 1/8” mini-jack cable), and the 740P
is connected to a 870A Amplifier via their respective
12V triggers (also using a 1/8” mini-jack cable).
When you turn on the 750D via remote control (or
its Standby button), both the 740P and 870A will
turn on automatically. The same rule applies when
you put the 750D 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 both the
preamplifier and 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 +4 Volts, the other
will be carrying a signal of –4 Volts. When these
two inverted signals on a balanced line are output
from the MOON 750D, 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.