Using Signal Sensing - Russound D850 Installation Manual

D850 and D1650 amplifiers have a signal sensing feature which will allow the
amp to turn on automatically when a signal from the source is "sensed". This is
useful if the source used with the D850 or D1650 amplifier does not have a 12v
trigger option.
There are many factors affecting the signal sensing of the D-series amplifiers,
and you can see a few recommendations and common scenarios listed below
to help set the levels in the system to best optimize the signal sensing feature.
This information is most useful when feeding a variable line level signal into
the amplifier. If the source being used with the amplifier is a fixed line level,
the amplifier should turn on and off consistently. If not, then some of the
troubleshooting tips below can help.
Keep in mind that the input signal will vary depending on the connected
equipment. For example, in the case of using a D-series amp to add additional
power to the zone outputs of an MCA multizone controller, the signal can vary
from zone to zone, and even from source to source. In this case, the MCA has trim
levels for both zones and source to even out the line level signals between the
different zones and sources.
Tech Spec: The threshold rating for the signal sensing is 4 millivolts at 1 KHz
RMS. This setting means that the sensing is sensitive to low signal levels. As a
comparison, an average line-level signal is about 2 volts. (Variable line outputs
will vary by nature, so these numbers are approximate.)
Common Practice: The way to get best results from Signal Sensing is to always
have a "hot" input signal, or in other words have the Source Input signal turned
up as much as possible, and to have the gains of the D-series amplifier set to
lower levels. There are going to be a wide variety of variables that will determine
how "hot" the input signal is, and every install and every scenario will be different,
however if the common practice is to have a the input signal turned up, and the
amp gains set lower, the signal sensing should be reliable for any given situation.
Steps to follow:
1. Set the D-series amp gains all the way down.
2. Turn the Source volume level up. Depending on the Source, it is usually
best to set the source volume level to about 80-90%, to avoid clipping the
signal.
3. Increase the gains of the D-series amp zone until the zone is at the loudest
level you would safely recommend for the installation, i.e. louder than what
the normal listening level would be.
4. Decrease the volume level of the Source down to normal listening level.
5. Turn the source off. The D-series amp will turn off after the set delay time.
6. Turn the Source back on. The D-series amp will turn back on.
7. See the troubleshooting section on page 11 if necessary.
Russound D850, D1650 Installation Manual

USING SIGNAL SENSING

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