The AC-12B is a wideband active monitor designed for bass players using digital modelling devices. The monitor is also prepared to work with analogue bass preamps. By connecting to the line out of another amplifier, the AC-12B can also be used as an extension of the sound system. The active monitor AC-12B is complemented by a PC-12B passive monitor. By combining these two speakers, a very good monitoring field on stage for the player and for the whole band can be created.

The AC-12B is equipped with two inputs to connect a mono or stereo signal. Also entire monitors signal from mixer's line out can be send straight to the AC-12B. Thus the bassist, beside of his own bass guitar's sound will also hear entire band's monitors mix. This is very important and very useful feature which allows very quick and precise adjustment of personal monitor mix on stage. The cabinets are equipped with neodymium speakers, which makes their weight and dimensions relatively small.

The cabinet is covered with hybrid polyurethane coating. The coating is extremely resistant to any kind of mechanical damage which may occur during transportation as well as protects the cabinets against moisture. It is also very easy to clean . An additional advantage of the coating with the polyurethane elastomer is a sealing and reinforcement of the entire cabinet's structure, thus eliminating undesirable vibrations as well as increases the overall cabinet's lifespan.