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Features
Inputs and Outputs Notes
Specifications
Features
Class D Amplifier: The XM-SD51X
amplifier is a Class D mono amp. Class D technology is a method to convert
and amplify music signals with MOSFETs to high-speed pulse signals. Class D amps
feature high efficiency and low heat generation.
Protection Circuitry:
This amplifier has 3-way protection circuitry which protects the amplifier in
the following cases:
- Thermal: Turns the amp
off when the operating temperature is too high
- Short Circuit: Turns
the amp off when the speaker outputs are short-circuited
- DC Offset: Turns the
amp off when a DC current is generated
LED: The
amplifier has an line of four LEDs on the top panel that glow blue when the amp
is on. There is also an LED that lights in red when the protection circuit is activated.
Low-pass Filter: The XM-SD51X
is equipped with a low-pass filter, continuously variable from 50-300 Hz, with a
slope of 12 dB/octave. It is constantly activate (cannot be switched off).
Bass Boost: For added low
frequency performance, this amplifier has a bass boost
centered at 40 Hz, variable from 0 to 10 dB.
Terminal Cover: The XM-SD51X
comes with a protective cap that fits over the power wire terminal strip to
help prevent accidental short circuiting.
Remote Level Control: A level
control is included that can be mounted in the front of the vehicle for easy
access. The remote is connected to the amp with the included cable (4 lead phone
cable with RJ-11 connectors at both ends). The width of the remote is 2.087",
height is 1.187", and depth is 2.196". Mounting hardware is included.
Inputs and Outputs
Notes
Speaker Outputs: Although this
is a mono amplifier, there are screw terminals for two speakers (each terminal
is 0.35" wide). They are not stereo outputs, but summed (L+R) mono, and
internally wired in parallel. If you connect two 4-ohm speakers to the amp, the
amplifier will see a 2-ohm load.
Power/Ground Terminals: The
power and ground screw terminals are 0.54" wide to easily accommodate 4-gauge
wire.
Remote Terminal: The remote
turn on screw terminal is 0.35" wide.
Speaker-level Input Harness:
The amp comes with a speaker-level input harness with a 4-pin Molex plug. This allows you to easily connect the amplifier to a factory radio or
a receiver without preamp outputs.
Preamp Output: This amplifier
includes a stereo preamp output, which allows you to send an unfiltered signal
to another amplifier. Note that you
must be using the line level input, not the speaker-level input, in order to use
the preamp output jacks.
Specifications
CEA-2006 Compliance: The
specifications given by Sony for the XM-SD51X amplifier comply with the new
CEA-2006 Amplifier Power Standard from the CEA (Consumer Electronics
Association). All manufacturers who comply with the standard can display the
CEA-2006 logo on their product.
RMS Power Rating
(measured at 14.4V): 250
watts x 1 into a 4-ohm load with an input voltage of 14.4 volts
Signal to Noise Ratio:
76 dBA (1 watt into 4 ohm load)
Note: Minimum impedance is 2
Ohms.
