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JL Audio A Series A1800
Mono subwoofer amplifier
1,000 watts RMS x 1 at 2 ohms
Item #: 136A1800
This item is no longer available.
JL Audio A Series A1800
Our take on the JL Audio A Series A1800 by Crutchfield's Buck Pomerantz
JL Audio builds their A-Series amplifiers with the high-end technology that's made their amps legendary. These hard-working amps feature an advanced thermal and low-impedance protection system that doesn't shut your amp down when the going gets tough. Instead, it rolls back peak voltage demands to protect the amp, while continuing to play your music at a safe power level.
The A1800 mono amplifier puts out up to 1,000 watts RMS, and JL Audio's patented Class-D amp circuitry keeps a tight rein on cone movement. JL Audio amps use "differential-balanced inputs" to isolate the signal's ground from the chassis ground, reducing noise and making this amp compatible with almost any system, including most factory radios.
A tunable low-pass filters and a bass boost give you precise control over your sound. The optional RBC-1 remote lets you dial in your bass from the comfort of your front seat.
What's in the Box:
- Monoblock subwoofer amplifier
- 2.5mm Allen wrench
- Owner's Manual
- mono subwoofer amplifier
- at 14.4 volts:
- 640 watts RMS x 1 at 4 ohms (1,000 watts RMS x 1 at 2 ohms)
- at 12.5 volts:
- 480 watts RMS x 1 at 4 ohms (800 watts RMS at 2 ohms)
- differential-balanced inputs
- Advanced Rollback Protection System
- variable low-pass filter (40-200 Hz, 12 or 24 dB/octave)
- switchable bass boost (0, 6 dB at 48 Hz)
- optional wired remote bass boost
- Class-D amplifier design
- MOSFET power and output stages
- preamp-level inputs
- speaker-level input with optional converter
- preamp outputs
- 4-gauge power and ground leads and a 80-amp fuse recommended wiring and hardware not included with amplifier
- no onboard fuses when installing multiple amps in a system, an additional 80-amp in-line fuse between the distribution block and the amplifier is recommended
- 16-1/8"W x 2-1/2"H x 9-1/4"D
- warranty: 2 years
- Our 60-day money-back guarantee
Features and Specs
|RMS Power Output (Watts x Channels)||
640 x 1
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||1000 x 1|
|Bridged Power (Watts x Channels)||N/A|
|Minimum Impedance Bridged||N/A|
|Minimum Impedance Unbridged||2|
|Best Frequency Response||10-250 Hz|
|THD at Rated RMS Power||1%|
|Signal to Noise Ratio||95 dB|
|Low-Pass Crossover Frequency||40-200 Hz|
|Low-Pass Slope (dB/octave)||12 or 24 dB/oct|
|High-Pass Crossover Frequency||N/A|
|High-Pass Slope (dB/octave)||N/A|
|Bass Boost||0 or 6 dB|
|Bass Boost Frequency||48 Hz|
|Speaker Level Inputs||RCA|
|Preamp Outputs||1 pair|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
Mono-Channel Subwoofer Amplifier: The JL Audio A1800 is a class D monoblock subwoofer amplifier that is rated at 640 Watts RMS x 1-channel in 4 ohm at 20 to 250 Hz with a signal-to-noise-ratio of 95 dB and a total harmonic distortion of 1% while receiving 14.4 Volts. The amplifier is rated at 1,000 Watt RMS x 1-channel in a 2 ohm load at 14.4 Volts. While receiving 12.5 Volts the amplifier is rated at 480 Watts RMS x 1-channel in 4 ohm with a total harmonic distortion of 0.08% or 800 Watts RMS x 1-channel in 2 ohm. The JL Audio subwoofer amplifier's frequency response is limited to the range of 10-250Hz and is not designed for driving midrange speakers or tweeters. Every aspect of the amplifier's operation has been optimized for low-frequency amplification.
Class D Circuitry: This JL Audio Class D subwoofer amplifier utilizes a proprietary Class D circuit. JL Audio's Patented Class D output circuit utilizes a discrete control section and a unique feedback loop design that results in outstanding power regulation and a damping factor greater than 500 at 4 ohms (>250 at 2 ohms). This is vastly higher than other Class D designs and also higher than most Class A/B amplifiers. The benefit of this exclusive JL Audio technology is tight, clean bass reproduction with the efficiency advantage of Class D amplification.
Simplified Gain Setting: The A-Series amplifier makes setting the gain level of the amp 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).
Differential-Balance 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 A1800 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 precision.
Note: You will need a speaker wire to RCA adaptor (136CLR2SW, sold separately) to connect this amplifier to your headunit via speaker-level.
Preamp Outputs: The A-Series amplifier features on pair of preamp outputs that make connecting multiple amplifiers simple. The preamp pass-through outputs are configured in parallel with the amp inputs. The signal present at these outputs is identical to the signal at the amp inputs and is unaffected by any on-board processing.
Active Crossover: The active crossover sections of the A-Series amplifier offer excellent flexibility and precise tuning. The A1800 features the following crossover adjustments.
Low Pass Filter: You can select a 12 dB/octave Low Pass or 24 dB/octave Low Pass. You can also turn the amplifier's Low Pass crossover off if you choose to use an external electronic crossover. In the Off mode the amplifier has a frequency range up to 250 Hz.
Filter Frequency: The filter frequency for the 12dB/octave or 24dB/octave Low Pass crossover can be set from 40 to 200 Hz.
Bass Controls: The bass boost circuit of the A-Series amplifier offers the following controls.
Bass Boost: The amplifier is equipped with a fixed +6dB, 48 Hz Bass Boost.
Remote Bass Port: The amplifier is equipped with a connection for a wired Remote Bass Control (136RBC1, sold separately) that allows fully variable boost control (0-12dB) from the front of your vehicle.
Advanced Rollback Protection: Should an A-series amplifier ever
intelligent, unregulated power supply reacts by limiting available peak voltage until the amplifier returns to a safe temperature range. Likewise, if an impedance lower than optimal for the amplifier is present at the outputs, the A-series amplifier will roll back peak voltage to protect itself without shutting down.
Note: There is only one condition that will shut down the A-Series amplifier completely and that is if the battery voltage of your vehicle drops below 10 volts.
Protection Circuitry With Status Indicator Lights: There are two status indicator lights on the right side of the amplifier.
Power (Green): This LED lights green to indicate that the amplifier is turned on and operating normally.
Protect (Red): The Protection LED lights Red to indicate the amplifier's protection circuitry has been activated to prevent product failure due to a short-circuit or a dangerously low impedance connected to the amplifier's outputs.
Left Side Of Amplifier:
Power and Ground: The JL Audio amplifier's set-screw Power and Ground connections are designed to accept 8 to 4 AWG power wire.
Remote Turn-On: The A-series amplifier's set-screw turn-on lead will accept 18 to 12 AWG wire.
Speaker Outputs: The A1800 amplifier's set-screw speaker terminals will accept 16 to 8 AWG speaker wire.
Right Side Of Amplifier:
Preamp Inputs: The amplifier features one set of differential-balanced RCA jack inputs. 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 amplifier also features one set of pass-through preamp outputs so you can send an unaltered audio signal to another amplifier in your system.
Remote Bass Port: The amplifier is equipped with a connection for a wired Remote Bass Control (136RBC1, sold separately).
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