HK Audio L SUB 1800 A - 18” Active Subwoofer for PA

HK Audio LINEAR SUB 1800 A – 18” Active Subwoofer for PA

The HK Audio LINEAR SUB 1800 A is an 18” self-powered subwoofer with a bass-reflex enclosure designed to deliver true low-frequency pressure and extension in professional PA systems. With a maximum SPL of 132 dB (peak, 10% THD) and a response that drops to 38 Hz (-10 dB), this subwoofer integrates naturally with LINEAR 3 and LINEAR 5 systems, and also functions as a bass extension in ELEMENTS Big Base configurations. It incorporates 1200 W (peak) Class D amplification, a 24 dB/oct subsonic filter and peak limiter, as well as active protections (undervoltage, thermal, short circuit and overcurrent) for reliable operation on the road and in events.

Its rear panel offers 2 balanced XLR/jack combo inputs , 2 XLR Thru outputs and 2 XLR Line Out Mid/High outputs with high-pass filter, allowing the creation of clean or stacked 2.1 systems without external processing. The selectable active crossover at 100/120 Hz (24 dB/oct) , 0°/180° phase switch and bass level control (±6 dB) simplify adaptation to the venue. Constructed from MDF with a black acrylic enamel finish , a steel grille with acoustic foam and an M20 plinth for stands, it combines durability with a compact size (51 × 67 × 72 cm) and a low weight (42 kg).

Main features

• Speaker: 1 × 18” with 3” coil.
• Enclosure: Bass-reflex optimized for punch and excursion control.
• Amplification: Class D, 1200 W (peak).
• Max. peak SPL: 132 dB (half-space, 10% THD); Max. average SPL: 130 dB.
• Frequency response: 42 Hz – X-Over (±6 dB) / 38 Hz – X-Over (-10 dB).
• Active Crossover: 100/120 Hz selectable, slope 24 dB/oct.
• Inputs/Outputs: 2 × balanced XLR/jack combo, 2 × XLR Thru, 2 × XLR Line Out Mid/High with high-pass.
• Controls: Bass gain ±6 dB, Phase switch 0°/180°.
• Protections: undervoltage, thermal, short circuit, overcurrent, 24 dB/oct subsonic filter and peak limiter.
• Auto Sleep Function: Saving mode when no signal is received.
• Construction: MDF with black acrylic enamel (RAL 9005), steel grille with acoustic foam.
• Mounting: M20 socket for satellite bar; 2 HK Audio MultiGrip handles.
• Dimensions (W × H × D): 51 × 67 × 72 cm; Weight: 42 kg.
• Power supply: 220–240 V~ 50/60 Hz; IEC connector with V-Lock retention.
• Input sensitivity: +4 dBu (center gain position).

Product benefits

• Deep, defined bass: true extension down to 38 Hz for electronic music, rock, or AV applications that demand impact.
• Plenty of headroom: 132 dB peak to adequately cover medium and large stages with fewer units.
• Easy integration: Selectable crossover, high-pass satellite outputs, and switchable phase make tuning easy without external processors.
• On-road reliability: a full suite of protections and a subsonic filter protect the driver in demanding situations.
• Quick assembly: M20 socket and MultiGrip for secure handling and stack or 2.1 configurations.

Use cases

• Bass reinforcement in LINEAR 3/5 systems for live gigs, DJs, and live music.
• Support subwoofer in ELEMENTS Big Base configurations for corporate events or mobile installations.
• Compact 2.1 systems with active tops using the filtered Mid/High outputs.

Frequently Asked Questions

• Can I use it in a 2.1 system? Yes. Connect your sources to the combo inputs, output the satellites from the XLR Line Out Mid/High outputs with the filter active and select the crossover frequency (100/120 Hz).
• Is it compatible with speaker bars? Yes, it has a standard M20 socket for bars and M20 studs.
• Does it include phase control? Yes, 0°/180° switch to optimize coupling with the tops.
• How many handles does it have? 2 integrated HK Audio MultiGrip handles.
• Does it have a power-saving mode? Yes, and it has an Auto Sleep function when there's no signal.

Description for projects

18” active bass-reflex subwoofer (3” voice coil) with 1200 W (peak) Class D amplification, max. SPL 132 dB (half-space, 10% THD), response 42 Hz – X-Over (±6 dB) / 38 Hz – X-Over (-10 dB), selectable active crossover 100/120 Hz (24 dB/oct), 2 × balanced combo XLR/jack inputs, 2 × XLR Thru, 2 × XLR Line Out Mid/High with high-pass, phase 0°/180°, input sensitivity +4 dBu, protections (undervoltage, thermal, short circuit, overcurrent, subsonic 24 dB/oct, peak limiter), M20 plinth, MDF construction with black acrylic enamel, steel grille with acoustic foam, dimensions 51 × 67 × 72 cm and 42 kg.