OPA 181 SP






The OPA-181SP is a single 18-inch high-output, low frequency subwoofer sytem. The OPA-181SP features multiple M10 rigging points that allow for either vertical or horizontal eyebolt syspension. The enclosure is designed for bi-amp applications and is optimized for use between 35Hz and 80Hz. Maximum system performance is achieved when 4th order filters are implemented. The recommended crossover frequency is between 80Hz and 100Hz.

The OPA-118 Sub is an ideal complement to On Point Audio’s full range enclosures, such as the OPA-12, the OPA-15YNP, and others.

The system utilizes a rectangular enclosure geometry. This geometry provides increased low-frequency response, due to its larger internal volume, as compared to a conventional trapezoidal enclosure.

The OPA-118 Sub is intended for use in professional bi-amp applications only. The On Point Audio OPA-118 Sub features an 18-mm void free plywood enclosure. The 18-inch (457mm) low frequency transducer offers excellent power handling and extended llinear excursion.

The input section consists of a single four position barrier strip. The nominal system impedance is 8 ohms.

The enclosure is built with high strength void free plywood and finished in On Point Audio’s Power Coat polyurea resin system.

  • Rectangular enclosure with multiple M10 rigging points.
  • High-performance 18-inch woofer with large- format 4-inch voice coil.
  • Vented design delivers usable response to 35 Hz DSP Signal Processing
  • Rated SPL max output 133dB (half space acoustic environment)
  • 130 dB / 127 dB max SPL (Peak / Continuous)
  • Void free multi-plywood enclosure with wear- resistant Power Coat polyurea finish.