HK Audio PORTABLE SUB Series: Universal Active Subwoofers
Seamless Bass Integration for Any Setup
The PORTABLE SUB series serves as the definitive low-frequency engine for the modern PA system. Engineered to provide a powerful, precisely controlled bass foundation, these active subwoofers are the ideal complement to the LUNAR series, while maintaining perfect, native compatibility with existing HK Audio systems including the POLAR MK2 and SONAR ranges.
One Subwoofer, Endless Possibilities
The PORTABLE SUB series follows a consistent system philosophy, ensuring seamless integration across the HK Audio ecosystem. By selecting a dedicated preset via an intuitive push button, the subwoofer automatically aligns its crossover and phase to match your chosen loudspeaker series. Whether you are using LUNAR for live sound, POLAR MK2 for column coverage, or SONAR for reinforcement, the PORTABLE SUB guarantees phase-stable, cohesive sound at the touch of a button.
This intelligent operating concept is designed to save time in high-pressure professional environments. The integrated 24-bit DSP technology ensures that the subwoofer adapts instantaneously to your specific system configuration. For scenarios requiring integration with loudspeakers from other manufacturers, a General preset with a 100 Hz low-pass filter is included, providing professional-grade flexibility without compromising on the precise, high-fidelity bass reproduction that defines the series.
Precision Engineering for Powerful Bass
With 1,400 watts of peak power and a maximum sound pressure level of up to 131 dB, these models deliver deep, well-defined bass that remains clean and punchy even at high volumes.
Integrated 24-bit DSP
Automatically optimises crossover and phase alignment for your chosen HK Audio system, ensuring perfect interaction and high impulse fidelity. The built-in limiter provides maximum headroom while protecting components from overload.
Fanless Power Amplifier
The high-efficiency Class-D design operates entirely without a fan, eliminating mechanical noise for quiet and noise-sensitive environments like corporate events or acoustic performances.
Stereo Preamplifier
Featuring built-in I/O, the subwoofer supports straightforward 2.1 system setups, allowing you to connect a stereo signal directly and route it to your top speakers without needing external components.
Professional Connectivity and Porting
Equipped with XLR/jack combo inputs and thru-outputs, the system adapts to any rig. Its open-port design increases acoustic performance and prevents airflow noise, ensuring cleaner bass reproduction.

Which Model is Right for You?
While both models share the same intelligent DSP and professional build quality, they are tailored for different performance requirements.
PORTABLE SUB 115 A
PORTABLE SUB 118 A
Built for Professional Demands
The sturdy enclosure ensures a clean, dry bass response and the durability required for professional mobile use. Ergonomically positioned MultiGrip handles facilitate safe, easy transport. Manufactured at the HK Audio site in St. Wendel, Germany, the series reflects a commitment to build quality backed by a five-year manufacturer warranty upon registration.
Whether you require the compact, punchy performance of the PORTABLE SUB 115 A or the additional low-end extension of the PORTABLE SUB 118 A, this series provides a scalable, high-performance foundation for mobile DJs, live bands, and installation professionals.
The specs
Concept: Active subwoofer
Cabinet principle: Bass reflex
Max. SPL peak3: 129 dB
Crossover frequency: 100 Hz / 80 Hz ->depends on Preset
Frequency range -6 dB: 42 Hz - X-Over
Frequency range -10 dB: 38 Hz - X-Over
COMPONENTS
Low frequency: 1x 15" with 3" voice coil
Crossover: X-Over with 24 dB/oct.
CONNECTIONS
Power supply: 1 x IEC connector
Analog input: 2 x XLR/jack combo symm.
Analog output: 2 x XLR Thru symm.
ELECTRONIC DATA
Preamplifier: Stereo preamp
Power amplifier: Class D - Biamped
Power amplifier output RMS: 700 W
Power amplifier output peak: 1400 W
Power consumption: 0,5 A / 220-240 V AC @ 1/8 output power 0,9 A / 100-120 V AC @ 1/8 output power
Maximum input level: 20 dBu
Speaker protection: Subsonic Filter, Peak and RMS Limiter
Sample rate: 48 kHz
Latency: 2ms - 3,3ms - depends on Preset
Filter presets: LUNAR, SONAR, POLAR, General LPF 100 Hz
MECHANICAL DATA
Cabinet features/rigging: 1 x M20 pole mount
Carrying handles: 2, MultiGrip
Cabinet material: MDF
Cabinet surface: acrylic enamel
Colour: Jet black (RAL 9005)
Front grille: Steel front grille, backed with acoustic foam
Dimensions (W x H x D), metric: 43 x 56,5 x 63,8 cm
Dimensions (W x H x D), imperial: 16-59/64 x 22-7/32 x 25-3/32 inch
Weight, metric: 32,8 kg
Weight, imperial: 72,32 lbs
Concept: Active subwoofer
Cabinet principle: Bass reflex
Max. SPL peak3: 131 dB
Crossover frequency: 100 Hz / 80 Hz -> depends on Preset
Frequency range -6 dB: 35 Hz - X-Over
Frequency range -10 dB: 31 Hz - X-Over
COMPONENTS
Low frequency: 1x 18" with 3" voice coil
Crossover: X-Over with 24 dB/oct.
CONNECTIONS
Power supply: 1 x IEC connector
Analog input: 2 x XLR/jack combo symm.
Analog output: 2 x XLR Thru symm.
ELECTRONIC DATA
Preamplifier: Stereo preamp
Power amplifier: Class D - Biamped
Power amplifier output RMS: 700 W
Power amplifier output peak: 1400 W
Power consumption: 0,5 A / 220-240 V AC @ 1/8 output power 0,9 A / 100-120 V AC @ 1/8 output power
Maximum input level: 20 dBu
Speaker protection: Subsonic Filter, Peak and RMS Limiter
Sample rate: 48 kHz
Latency: 2ms - 3,3ms - depends on Preset
Filter presets: LUNAR, SONAR, POLAR, General LPF 100 Hz
MECHANICAL DATA
Cabinet features/rigging: 1 x M20 pole mount
Carrying handles: 2, MultiGrip
Cabinet material: MDF
Cabinet surface: acrylic enamel
Colour: Jet black (RAL 9005)
Front grille: Steel front grille, backed with acoustic foam
Dimensions (W x H x D), metric: 51 x 61,5 x 70,3 cm
Dimensions (W x H x D), imperial: 20-5/64 x 24-3/16 x 27-21/32 inch
Weight, metric: 39,3 kg
Weight, imperial: 86,65 lbs