JL Audio RD500/1 Monoblock 1 Channel Class D Sub Subwoofer Amplifier 500w RMS

RD500/1

Monoblock Class D Subwoofer Amplifier, 500 W

RD500/1

Monoblock Class D Subwoofer Amplifier, 500 W x 1 @ 2 Ω / 250 W x 1 @ 4 Ω - 14.4V

Born to produce a whopping 500 watts into 2 ohms (14.4V, 1% THD), the RD500/1 amplifier was engineered to generate tons of pure subwoofer bliss from a sleek, ultra-compact chassis. The secret behind its power proficiency is our proprietary NexD™ switching technology, which delivers large amounts of power output with precise efficiency and ultra-low distortion.

For your convenience, the RD500/1’s controls are located on top of the amplifier, beneath a protective cover, with all connections found along one side of its chassis. Signal processing features include a 12 dB / octave low-pass filter, with continuously variable frequency selection from 50-500 Hz, and a variable bass boost EQ. Dual-range, differential-balanced inputs are also on-hand, capable of accepting most input voltage levels. Automatic turn-on capability (via signal sensing or DC-offset sensing) is standard, along with a set of preamp outputs so you can easily pass signals to another amplifier.

The RD500/1 is also equipped with an onboard LED-clipping indicator. This all-new, innovative feature lets you easily set your amplifier’s input sensitivity setting, quickly and accurately, with no special equipment needed. The RD500/1 features a durable, black powder-coated finish and a top-mounted, dual-color LED light strip that reports the overall status and condition. With the addition of an RBC-1 remote level control (sold separately), you can control the subwoofer output directly from the driver’s seat.

NexD™ Switching Technology

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

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.