Monoblock Wide-Range Class-D Amplifier:
The JL Audio HD1200/1 is a very powerful and
compact monoblock (single channel), wide-range amplifier utilizing patented
Single Cycle Control Class D technology. This technology delivers reference
grade sonic performance while requiring far less current from the vehicle's
electrical system than a conventional amplifier. Unlike most monoblock
amplifiers, the HD1200/1 is a wide-range design (freq. response: 6 Hz - 8 kHz) so it can be used as a subwoofer
amplifier or to drive high-performance midrange speaker systems.
Amplifier Rating: The JL Audio HD1200/1 Class D
monoblock, wide-range amplifier is rated at 1200 Watts RMS x 1-channel at
1.5 to 4-ohm at 20-20kHz with a signal-to-noise-ratio of 110 dB and a total
harmonic distortion of 0.03% while receiving 11 to 14.5 Volts.
High-Fidelity Class D (HD) With Single-Cycle Control: The JL Audio
HD1200/1 utilizes Single Cycle Control Class D technology
for all channels. This patented technology delivers reference-grade sonic
performance while requiring far less current from the vehicle's electrical
systems than a conventional amplifier.
Compact/Efficient Design: The JL Audio Class D amplifier on average is
13% smaller overall and over 1/2-inch shorter in height than most class AB
amplifiers. The HD1200/1 features outstanding overall efficiency (80% at 1/2
rated power) which allows for huge power from a tiny chassis and is easy on your
vehicle's charging system, drawing 60% less current than a class AB design of
R.I.P.S. (Regulated, Intelligent Power Supply): R.I.P.S. stands for
"Regulated, Intelligent Power Supply" and is a central feature of the JL Audio's HD amplifier. The JL Audio R.I.P.S. System ensures consistent power
delivery over a wide range of battery voltages and load impedances. This
technology provides optimum power at any impedance level between 1.5 ohm to 4
ohm per channel and at any vehicle voltage level between 11V and 14.5V.
- Regulated Power Supply: "Regulated" means that the power supply
adjusts its operation so as to maintain the amplifier's rated power output
and low distortion operation over a wide range of vehicle voltages (11V-14.5
V). This allows the JL Audio HD amplifier's the rail voltage and clean
power output to remain stable in real-world car-audio systems, resulting in
superior fidelity and stability.
- Intelligent Power Supply: The "Intelligent" portion of the
R.I.P.S. System is a circuit that actually monitors output current to
optimize the amplifier's output power over a wide range of load impedances
(1.5 ohm to 4 ohm per channel). The R.I.P.S. System detects the actual
impedance being driven and adjusts output rail voltages to deliver optimum
output. The entire process is seamless, automatic, and results in incredible
dynamics for satellite channels and consistent power output for a wide range
of subwoofer configurations. It also takes into account the real impedance
of your car-audio system, rather than relying on often inaccurate
assumptions based on a speaker's rated impedance.
RealSink Heat Management With Rollback Protection:
This JL Audio amplifier employs an advanced type of heat management, called RealSink. This features takes advantage of
convection and radiation effects to remove heat from the amplifier circuitry.
For optimum cool performance, the vertical heat sinks located at the sides of
the amplifier should be exposed to as large a volume of air as possible.
If a JL Audio HD amplifier should ever reach an unsafe temperature, its unique
Advanced Rollback Protection circuit also adjusts power until the amplifier
cools down, without ever shutting your music down.
Differential-Balanced Inputs: The JL Audio amplifier features
differential-balanced input architecture to effectively control noise and ensure
compatibility with a wide variety of source units, including many OEM
systems. Without resorting to line output converters, you can directly connect
most OEM source units to the JL Audio amplifier without creating any noise or
compatibility issues. Unlike conventional single-ended inputs, the
differential-balanced design does not connect one side of the audio signal to
chassis ground. This eliminates any voltage sensitivity between one input
terminal and ground and greatly reduces the incidence of alternator whine in a
typical car audio installation. The JL Audio HD amplifier provides range switching
on each of its inputs via the "Input Voltage" switch. This permits connection to
a wide range of source voltages while retaining excellent sensitivity setting
Note: You will need a speaker wire to RCA adaptor (136XDCLR2S,
sold separately) to connect this amplifier to your headunit via
Protection Circuitry With Status Indicator Lights: There is
a single multi-color LED on the control panel of the amplifier to indicate the
amplifier's operating status.
- Flashing Green: When
the LED is flashing green, the amplifier is powering up and audio output is
- Constant Green: This LED lights green to indicate that the
amplifier is turned on and operating normally.
- Constant Red: This Red LED lights to indicate that the amplifier
has exceeded its safe operating temperature, putting the amplifier into a
shelf-protection mode, which reduces the power output of the amplifier. The
red light will shut off and the amplifier will return to normal, full-power
operating mode if the heat sink temperature drops back to a safe level.
- Constant Yellow: This amber LED lights to indicate that the
impedance of the speaker load connected to the amplifier is lower than the
optimum impedance load range for the amplifier. When this light is on, a
protection circuit engages and reduces the power output of the amplifier.
The amber indicator will also light when a short-circuit is detected in the
- Alternating Red/Green: The LED alternated between Red and Green to
indicate that the amplifier is experiencing a fault that may require service
of the amplifier, its wiring, or the vehicle's operating system. Audio is
muted when this fault occurs.
Note: Only one condition will shut down the HD1200/1 completely--if the battery voltage of your vehicle
drops below 10 volts.
Mounting Options: The HD1200/1 has two mounting options to
choose from during installation:
- Standard Mounting: The standard method of mounting
requires removal of the four corner caps with the 4mm Allen wrench included with
the amplifier. Using the appropriate mounting screws (not included), you can
then secure the amplifier in all four corners and replace the corner caps.
- Lateral Mounting Feet: Lateral Mounting Feet are also included
with the HD1200/1 to provide an alternative mounting option. Each mounting
foot should be attached to the bottom of the amplifier by screwing the
provided bolts into the bottom of the amplifier and up into the corner cap
with the supplied 2.5mm Allen wrench. Then, using the appropriate
mounting screws (not included), you can secure the amplifier by its four
lateral mounting feet.
Stacking: With the optional
HD Stack Kit, you can stack one HD amp on top of another HD amp.
Control Panel Cover: The
HD1200/1 features a Control Panel Security Cover which protects and hides the
amplifier's controls. When installed, the cover ensures that the amplifier's
settings are not accidentally changed while creating a clean aesthetic look for
the amplifier and your installation. The control panel security cover is
pre-installed at the factory and must be temporarily removed for access the
amplifier's controls. The security cover is secured by a single 2.5mm Allen-head
Simplified Gain Setting: The amplifier's R.I.P.S. feature
also allows for easy gain setup. Because the amplifier will always deliver the
same amount of power within its operational range of impedances and supply
voltages, the maximum, unclipped output is very predictable. This makes setting
the gain level of the amplifier via the input sensitivity control very simple.
All you need is Digital AC Voltmeter (142TK12V, sold separately) and a Test CD Disc (503CD104,
sold separately) with a sine-wave test-tone recorded at 0 dB reference level in
the frequency range to be amplified for that set of channels (50 Hz for
subwoofer channels, 1 kHz for a midrange application).
Flexible Input Section And Active Crossover Network: The JL Audio HD amplifier provides a
flexible input section and a comprehensive
crossover network to fine tune your system effectively and accurately. The
variable filter design employed in the JL Audio HD amplifier crossover sections
allow you to seamlessly switch slopes, easily change filter frequencies and
address what frequencies the preamp outputs will pass. The HD1200/1 offers the
following independent crossover adjustments behind a removal cover plate:
- Input Voltage: The wide range of signal input voltages
is divided into two sub-ranges. You can select "Low" if the input is 200mV
to 2V, or "High" if the input is 800mV to 8V.
- Filter Mode: The amplifier features a variable
Low-Pass or High-Pass filter mode for the amplifier's preamp input
section. The filter can also be turned off for wide range operation.
- Filter Slope: When the low-pass or high-pass filter is
active, you can choose between a 12dB/octave Butterworth filter or
24dB/octave Linkwitz-Riley filter.
- Variable Frequency:
The cutoff frequency for the filter can be set between 50 and 500 Hz.
- Infrasonic Filter: The Infrasonic Filter is a 24 dB/octave
high-pass filter, with a fixed cutoff frequency of 30 Hz. This filter is
designed to conserve amplifier power and protect subwoofer systems, without
audibly degrading the sub-bass output. You can set the filter to On or Off.
Output Polarity Control: Depending on the distance relationship of the
mid-bass speakers and the subwoofers in your system, it can be desirable to
reverse the polarity of the subwoofer system in order to produce a better
transition between subwoofer and midbass speaker output. The amplifier's Output
Polarity switch allows you to quickly perform this polarity inversion.
The amplifier features a Power Connection plug which detaches from the
amplifier to make connecting your power, ground, and remote turn-on lead wires
more convenient. Allen wrenches are supplied for tightening or loosening the
set-screws. Once your connections are made, the Power Connector simply plugs
into the amplifier.
- Power and Ground:
The amplifier's set-screw Power and Ground
connections on the detachable Power Connection plug are designed to accept up to
4 AWG power wire. For power wire runs of more than 72", a minimum of 2 AWG
wire should be used from the battery to a fused distribution block, then
reduced to 4 AWG wire near the amplifier.
- Remote Turn-On: The amp's set-screw turn-on lead
receptacle on the Power Connection plug will accept 18 to 12 AWG wire.
Note: The Amplifier is not equipped with a fuse. An
external 100-amp AFS, ANL, or MAXI fuse (not included) must be installed on
the power wire. If a wiring kit is used which includes a fuse with a value
other than 100-amps, the original should be replaced with a 100-amp fuse.
Speaker Output Plugs:
The amplifier features one Speaker Output plug which detaches from the amplifier for
easier speaker wire connection. Once your speaker wires are connected to these
plugs, they simply push into the amplifier. The Speaker Output plug features
four set-screw terminals for an easy parallel subwoofer connection. The HD1200/1
amplifier's four set-screw speaker terminals found on the Speaker Output plug
will accept 16 to 12 AWG speaker wire. A 2.5mm Allen wrench is supplied for making
Preamp Inputs: The amplifier features one set of differential-balanced
RCA jack inputs. The amplifier features a
dedicated Input Sensitivity gain control for these inputs. These controls are designed to match the input sensitivity of the
HD1200/1 to the specific signal source that is feeding it. The amplifier's input level can be set to Low (200mV-2V RMS)
when connecting the amplifier to a low-level preamp signal or set to High
(800mV-8V RMS) when connecting the amplifier to a high-level speaker signal.
Preamp Outputs: The HD1200/1 incorporates a pass-through preamp output
sections, so that additional amplifiers can easily be connected to the same signal feeding the
HD1200/1. The preamp output signals are buffered to
prevent noise and are always preamp level, regardless of the level of signals
feeding the HD1200/1's inputs.
Remote Level Control: The amplifier features a RJ-14 standard
telephone connector for adding an optional wired remote level control. With the
addition of the optional wired
HD-RLC Remote Level Control (sold separately), you can control the volume
of the HD1200/1 form the front of your vehicle. This
is useful for subwoofer level control. If desired, multiple HD amplifiers can be controlled from a single
HD-RLC controller using a simple phone line splitter and multiple phone cables
(all sold separately).
Note: All inputs and outputs are located on the
rear of the amplifier to make installation of the amplifier simple and neat.