Monoblock Class D Marine Subwoofer Amplifier, 600 W x 1 @ 2 Ω / 400 W x 1 @ 4 Ω - 14.4V

This potent monoblock amplifier employs our high-speed NexD™ switching design to achieve unprecedented efficiency and amazing power output in a very compact chassis. Don't let the small size fool you, though... this amplifier is capable of serious subwoofer power, delivering a full 600 W of continuous power into a 2 Ω load (14.4V, 1% THD).

Dynamic Motor Analysis - DMA Optimized Motor

Summary:
JL Audio's proprietary Dynamic Motor Analysis system is a powerful suite of FEA-based modeling systems, first developed by JL Audio in 1997 and refined over the years to scientifically address the issue of speaker motor linearity. This leads to vastly reduced distortion and faithfully reproduced transients... or put simply: tight, clean, articulate bass.

Detailed Information:
Since 1997, JL Audio has been at the forefront of Finite Element Analysis-based modeling of loudspeaker motors and suspensions. This research is aimed at decoding what we refer to as the "Loudspeaker Genome"... a project aimed at understanding the true behavior of loudspeakers under power and in motion. A major component of this integrated system is DMA (Dynamic Motor Analysis). Starting with the 15W3 and the W7 Subwoofers in the late 1990's and early 2000's, DMA has played an important role in the design of all JL Audio woofers sold today, including our component woofers.

DMA is a Finite Element Analysis (FEA)-based system, meaning that it takes a large, complex problem, breaks it down into small solution elements for analysis and then assembles the data to form an accurate, "big-picture" solution. DMA's breakthrough is that it actually considers the effects of power through the coil as well as coil/cone position within the framework of a time-domain analysis. This gives us a highly accurate model of a speaker's actual behavior under real power, something that the traditional Thiele-Small models or other low power measurements cannot do. Because DMA does not rely on a steady-state model, it is able to consider shifts in the circuit elements being analyzed. These modeling routines are intense, requiring hours to run for a whole speaker.

DMA is able to analyze the real effects of fluctuating power and excursion upon the magnetic circuit of the motor, specifically the dynamic variations of the "fixed" magnetic field. This delivers intensely valuable information compared to traditional modeling, which assumes that the "fixed" field produced in the air gap by the magnet and the motor plates is unchanging. DMA not only shows that this "fixed" field changes in reaction to the magnetic field created by current flowing through the voice coil, but it helps our engineers arrive at motor solutions that minimize this instability. Analyzing this behavior is critical to understanding the distortion mechanisms of a speaker motor and sheds light on the aspects of motor design that determine truly linear behavior:

1. Linear motor force over the speaker's operational excursion range
2. Consistent motor force with both positive and negative current through the coil
3. Consistent motor force at varying applied power levels
    

Our ability to fully analyze these aspects of motor behavior allows our transducer engineers to make critical adjustments to motor designs that result in extremely linear, highly stable dynamic loudspeaker motor systems.

The payoff is reduced distortion, improved transient performance and stellar sound quality.

NexD™ Switching Technology

Summary:
NexD™ amplifier technologies produce exceptional audio quality, unsurpassed total efficiency and high power from very compact amplifier designs.

Detailed Information:
Beginning with the original 'Slash' subwoofer amplifiers, JL Audio has been at the forefront of Class D amplifier design. Our NexD™ switching technology stems from our Class D expertise to deliver outstanding fidelity and efficiency, leading to compact amplifiers that deliver high power and exceptional value.

Let's get a little nerdy... A traditional PWM switching amp design uses a fixed switching frequency and varies the pulse width based solely on the audio input signal to the pulse modulator. This basic approach assumes some ideal conditions, like a rock-steady power supply, that do not necessarily occur in a real, in-car installation. Power supply sag with signal causes distortion at all power levels with these designs, even well below clipping. The cure for this is feedback (a corrective signal sent back to the input side), but this becomes impractical as the audio frequency increases, making it a good solution for band-limited (subwoofer) amps, but not for full-range amplifiers.

Taking the above into account when designing the NexD™ subwoofer amplifiers, we have taken the simple fixed PWM approach and enhanced it with a very high switching frequency: 240 kHz, which is about 4x higher than most Class D subwoofer amplifiers. This pushes the amplifier's bandwidth to at least 500 Hz with minimal distortion and improves efficiency, while keeping typically bulky circuity more compact. Your subwoofers will reward you with tight, rock-solid bass performance.

For the full-range NexD™ amplifiers and channels we applied a variable, ultra-high speed version of the NexD™ technology (switching at well over 400 kHz). In these designs, a self-oscillating modulator with "feed-forward" sends information about the instantaneous power supply voltage to the modulator, combining this with the input signal to cancel out any distortion due to supply voltage fluctuation. This reduces distortion prior to applying feedback, simplifying the overall feedback loop design.

The bottom line is simply great audio: clean, powerful and reliable.

Advanced Rollback Protection

Summary:
JL Audio's exclusive Advanced Rollback Protection circuit monitors the amplifier's thermal condition and adjusts amplifier operation to eliminate annoying amplifier shut-down events.

Detailed Information:
Should a JL Audio amplifier equipped with Advanced Rollback Protection reach an unsafe operating temperature, a special circuit rolls back peak power output, without changing gain, until the amplifier cools down to a safe operating temperature. The condition is generally indicated by a red “Thermal” or “Status” LED state. On VXI amplifiers, the LED ring will flash red. Once the amplifier cools down, the circuit restores full peak power output and the indicator reverts to its normal state. The operation of Advanced Rollback Protection is inaudible in most cases, but it ensures that your music keeps on playing, even under the most demanding conditions.

Find the answers to many common questions:

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U.S.A. Warranty Information - Marine Amplifiers and Electronics

JL Audio Marine Amplifiers and Electronics are warrantied against defects in materials and workmanship for Two (2) Years from purchase date. JL Audio will, at its discretion, repair or replace any products that exhibit defects in materials and/or workmanship during the warranty period.

Please hold on to your sales receipt! All warranty service requires original sales receipt documentation. The warranty only applies to the original purchaser from an authorized retailer.
Note: Products purchased from unauthorized dealers are not covered under warranty.


Warranty Limitations

The following is not covered under JL Audio's warranty program:
1. Product with defaced, altered or removed serial numbers (no valid, legible serial number = no warranty).
2. Product owned by anyone other than the original purchaser from an authorized JL Audio dealer. (The warranty is not transferable and will not apply to products purchased from unauthorized dealers.)
3. Product that has been physically abused (run over by a car or beat with a hammer, for example).
4. Product that has not been installed according to the instructions in the owner's manual
5. Product in which repair and/or modification has been attempted by unauthorized parties
6. Product damaged cosmetically due to improper handling or normal wear and tear
7. Product damaged in an accident, due to criminal activity (attempted theft, gunshot damage, etc.) or by 'acts of God' (flooding, lightning, locusts, etc.)
8. Custom finishes or other cosmetic treatments applied to products. (JL Audio will not be responsible for restoring or maintaining any custom finishes)
9. Installation and shipping costs associated with removing, re-installing or shipping the product to JL Audio for warranty service
Ask your dealer for details on warranty limitations.


If you need Service on your JL Audio Product:
All warranty returns should be sent to JL AUDIO freight prepaid through an authorized JL AUDIO dealer and must be accompanied by proof of purchase (a copy of the original sales receipt.) Direct returns from consumers or non-authorized dealers will be refused unless specifically authorized by JL AUDIO with a valid return authorization number. Warranty expiration on products returned without proof of purchase will be determined from the manufacturing date code. Coverage may be invalidated as this date is previous to purchase date. Return only defective components. Non-defective items received will be returned freight-collect. Customer is responsible for shipping charges and insurance in sending the product to JL AUDIO. Freight damage on returns is not covered under warranty. Always include proof of purchase (sales receipt).

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Voted "Favorite Stereo Manufacturer"
– 2011 Reader's Choice Awards, Powerboat Magazine

"Our customers are thrilled with the incredible sound quality of the JL Audio systems we're installing in our boats."
– Ariel Pared, SeaVee Boats

"We tested a boat with a complete JL Audio system... The clarity and power emitted by this system was second to no other boat system on any boat, of any size, we have ever heard. It was a truly amazing experience."
– Tony Adelo, Mayor's Cup Magazine

"My JL Audio sound system can turn a bad day of fishing into a fun day on the water."
– Captain Rimmer Covington, Owner - Mexican Gulf Fishing Company