The HK Audio SONAR 115 Sub D Subwoofer in Black is a powerful, state-of-the-art powered subwoofer. The particularly powerful 15-inch woofer, the 1500-watt power amplifier and the meticulous HK Audio acoustic engineering guarantee an impressively powerful bass experience.Illuminated LCD ScreenThe SONAR 115 Sub D is controlled by a 24-bit DSP with an illuminated LCD screen, which can be used to conveniently adjust the crossover frequency, polarity and, if necessary, the delay. Cardioid Rear PresetThe SONAR 115 SUB D meets all the requirements, both mechanically and acoustically, to implement effective cardioid setups quickly and easily, reducing the low bass radiated to the rear by up to 30 dB. This not only makes performing on stage much more relaxed, it also results in a better sound, as microphones no longer pick up unwanted low frequencies. A second SONAR 115 Sub D can be used to increase the sound pressure level in the bass range. The classic full-stack setup (shown on the left) with two subs projecting forward boosts the sound pressure by level 3 dB in all directions. But what makes the SONAR 115 Sub D so special are its cardioid capabilities. It has two special presets that allow you to configure a cardioid setup, where the lower sub projects to the rear, without the need for any complex calculations or time correction.