BF181 mkII

BF181 mkII - compact subwoofer

  • High-output, direct-radiating 18” subwoofer system
  • Extended-excursion vented-spider 18” woofer
  • X-venting™ for maximum breathing capacity
  • SIS™ pre-wired for very high damping and further reduced distortion (with ALC)
  • Low impedance for efficient amplifier loading
  • Front-positioned NL4 connector for easy cardioid connection

Product description

The BF181 is a high-performance subwoofer system, designed to deliver tight and accurate bass response with very low distortion.
It features a single 18” long-excursion woofer, with vented double-spider frame and 4” voice-coil, for a stable and prolonged high output.

The direct-radiating woofer is mounted in a vented chamber; exiting into the  X-Venting™ bass reflex port: This centrally located port takes more than 25% of the baffle surface and is designed to maximise the system’s breathing capacity, increasing overall output while minimising port-compression.

The double baffle board and the combination of complex internal panel lay-out with extensive bracing brings a rigid structure with a high enclosure stiffness from a relatively low-weight package. It is finished in Durotect™ scratch-resistant coating and is fitted with 2 handles for easy logistics (road-version).

For full system performance, the BF181 is driven and controlled by the ALC amplified loudspeaker controller; Driven by the ALC, the BF181 delivers maximum sound quality and output power with long-term operation reliability. The integrated factory presets in the drive processor of the ALC offer gain, phase and filtering matching with all Alcons top systems; Also selectable response characteristics are available; “sub”, “bass”, “punch”, as well as cardioid projection control presets. The additional front-positioned NL4 connector caters for easy “reverse connection” in cardioid arrays. The 4 ohms system impedance, makes for a very efficient amplifier loading.

The BF181 is SIS™ pre-wired: Through the Signal Integrity Sensing circuit of the ALC, the cable-length and connector resistance between the BF181 and ALC is dynamically compensated (system damping factor 10.000), further reducing distortion, while increasing response accuracy.

The BF181 is available in road-version and installation (“i”) version, without handles, wheel dolly board and M20 threaded stand mount flange. Through the Architect Color Option™ program, the BF181 can be finished in any RAL™ color.

Dimensional drawing

Technical specifications

Frequency response 36 Hz - 200 Hz (+/- 3 dB)
30 Hz - (+/- 10 dB)
Sensitivity nominal 99 dB (40 Hz - 100 Hz)
Nominal impedance   4 ohms
Recommended drive Sentinel3 min.
Nominal SPL peak 128 dB (Sentinel3 40 Hz - 100 Hz)
133 dB (Sentinel10 40 Hz - 100 Hz)
138 dB (comparative)
Dispersion H x V omni / (hyper) cardioid
in array with processing

Physical specifications

System   subwoofer, front loaded
Drivers LF   1x AW18.4/4 18” vented
Connectors   3x Speakon NL4 input/link
Physical dimensions   mm        inches
Height   613         24.1
Width   596         23.5
Depth   712         28.0
Weight (approx.) BF181   53,6 kg    118.2 lb
                             BF181i   45,7 kg    100.8 lb
Warranty   6 years limited


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