The P.Audio XT-18A Sub was designed to complement the passive mid-hi cabinets in the XT series, which are available in sizes from 8 to 15 inches. The XT-18A Sub uses an on board two channel amplifier to pr ovide 1500w peak amplification to the 18” low frequency woofer, and also provides 500w peak amplification to the Speakon connector on the rear of the cabinet. This can be connected to a mid hi cabinet from the XT series to provide complete, simple set up using minimal time and effort. System performance can also be monitored and customised to the user by use of the optional cable adaptor and the XT Series computer softwar e. This software provides full control of delay, system gain, and equalisation using the powerful DSP. The amplifier also provides 8 presets on the rear of the amplifier for connecting to each of the XT Series mid-hi cabinets, a pink noise generator, and 2 user presets. The cabinet design is based around a large 18” woofer mounted into a bass reflex cabinet to provide extra low frequency extension. The cabinet is made from plywood, and covered in an extremely durable polyurea coating to ensure the system is truly road-worthy. The full face grill is made from 1.5mm thick steel to ensure the transducer is well protected. The XT-18A Sub can be used in both fixed installation and portable environments, but excels at small to medium scale sound reinforcement where there is a requirement for quick set up, ease of use, and considerable low frequency extension.