The XJ 600  - Power, Control and flexibillity

The XJ 600 is a unique monoblock subwoofer amplifier. XJ 600 is equipped with several advanced features that make it ideal for powering subwoofers or tactile shaker units.
XJ 600 distinguishes itself from traditional power amplifier by  Earthquakes unique class J amplifier circuit. Class J features  interface velocity controlled output and Look-Ahead technology. This technology enables high power and continuous operation in a demanding  2 ohm impedance.

Besides the high efficiency the XJ 600 amplifier is equipped with DSP containing  both EQ, phase and time correction. Earthquakes Overdrive and ODL technology ensures that all power resources are used safely and optimally

Flexibility
Keywords for this amplifier is flexibility, power, control, and adaptability. All areas of the amplifier can be aligned and optimized by the user. It can therefore be used in every imaginable bass (LFE)  situation.
It is the perfect amplifier for the advanced enthusiast who wants full control and ability to adjust all parameters of operation.
Similarly, it can easily be used by the novice user who wants large amounts of power from a compact and efficient amplifier.

XJ 600 shares many similarities with the IQ 600 plate amp and could replace a plate amp if you want your sub woofer amplifier separate.
XJ600 is passively cooled for silent operation.

Full DSP for total control
Several manufacturers different measures of room correction built into their sub woofers. Most are based on level adjustment by volume, which is a very simple equalization function. EQ does not consider the room’s phase related difficulties.
XJ 600 amplifier has genuine room correction which takes account of reflections, refractions, arrival and EQ. This complete DSP solution results in optimum acoustic alignment in any room.

The room correction in XJ600 is simple and straightforward to use.

1. Place the subwoofer at the desired location.
2. Play a 50 Hz test tone, turn phase delay button until the maximum output is reached. 
3. Using phase-switch button to turn the phase 180 degrees, and then turn the phase-delay button until the highest level reached. 
4. The option – 0 or 180 degree phase that needs the least amount of phase-delay to achieve the highest level – is optimal because it will give the least group-delay 
5. Now the phase-related correction is completed and regular EQ with 3 band equalizer can be started.
   

Unlimited power surplus
The brute force of the Xj600  springs from the class J amplifier. The patented Class J technology manifests a quantum leap in amplifier technology. The revolutionary aspect of Class J is its ability to combine a high efficiency of 99% with extraordinary bass control. Class J is an evolution on PWM technology that combines advanced multi-level feedback with an intelligent controller. It modulates the supply voltage and output switching frequency in real time based on the frequency and amplitude content of the input signal. This added level of intelligence to the amplifier offers several obvious advantages such as increased thermal headroom through the amplifier's optimum energy use, dramatically improved bass response and dynamic power capabilities. This results in a harder audible impact that adds a drive to the sound normally experienced only at live concerts. This combined with superb articulation, nuances and details are reproduced by the MKVI, but overlooked by traditional subwoofers.

Real specs
The patented technologies combined with a dramatically oversized power supply makes the XJ600 amplifier capable of delivering raw quantities of continuous power. The power supply is based on a rigid silicon-steel hard-wound Pancake low regulation 750VA toroidal transformer. The large and heavy transformer ensures a stable supply without voltage drop even at rigorous and continuous operation. The XJ 600 amplifier provides 1200 watts continuously for unlimited time at 18 dB crest factor and 600 watts TSP (True Sine Wave Power). This is real power the amplifier can deliver in the very tough 2 Ohm load. The ability to drive 2 Ohm loads enables the XJ600 amplifier to operate two 4 ohms woofers or four 8 Ohm woofers.

Overdrive - Optimal use of all power reserves
Overdrive is a patented system that gives the amplifier exceptional high dynamic output. The starting point for the Overdrive system is a constant monitoring of all amplifier power resources coupled with an intelligent dynamic high voltage supply. Information from the power amplifier is translated by the overdrive system into a dynamic power matrix which calculates the dynamic power potential in real time. A traditional amplifier will attempt to reproduce a transient signal although its duration exceeds the amplifier's resources which leads to speaker damaging distortion. Overdrives patented design ensures distortion-free amplification combined with optimal and safe use of all power resources. Sound is dynamic by nature therefore optimization of dynamic power resources is essential. Overdrive provides a peak power double the XJ600's nominal specification making the amplifier capable of reproducing 1200 watt program material.

ODL - Intelligent Protection
The patented Optical Distortion Limiting circuit is a revolutionary design that provides full protection against overdriving and distortion. The uniqueness of this design is that the audio signal remains immaculate, as ODL is not in the signal path. Traditionally, the signal runs through the protection circuit thereby complicating the signal path. ODL is unique because it insulates the protection circuit behind an optical coupler. The delicate input signal meets a Y-sensing and the signal is duplicated. The original signal continues  untouched to the amplifier section. The duplicated signal is translated into light where ODL compares it with the power amp section. The use of light gives ODL a response time unattainable in a conventional design. If ODL detects an overdriven signal that can not be amplified nominally or by Overdrive, ODL ensures distortion-free amplification by adjusting the input power in real time.

Specifications:

• 1200 watts dynamic power
• 750 watts continuous power 
• Earthquake class J amplifier 
• Frequency Response: 10-2000 Hz 
• Adjustable 24dB low-pass filter with bypass. 
• Selectable subsonic filter @ 25Hz by 12dB steepness. 
• No output below 10Hz via modulator limitation. 
• Manual on / off switch 
• Auto on / off switch 
• IR input and remote control with volume control 
• Crossover with bypass switch 
• Subsonic filter 
• Phase delay up to 20 milliseconds
• Phase switch 
• Manual channel 1 and 2 gain adjustment 
• Full and advanced room correction 
• RCA input 
• Balanced XLR inputs 
• High Level Speaker Output