Bose L1 Model II System Double Bass Package. Spatial DispersionTM and Articulated Array speaker technologies in the loudspeaker produce wide, uniform sound coverage. Integrated power amplifiers in the power stand provide clean, precise amplification for L1 Model II system with up to two B1 bass modules. ToneMatch port on power stand for digital audio and power connection to ToneMatch audio engine. Integrated power amplifiers in power stand deliver clean, precise amplification for L1 Model I loudspeaker and up to two B1 bass modules. Analog input, trim control and signal/clip LED for line-level analog input via " TRS phone cable. The 24 small drivers are arranged using Articulated Array speaker technology in a slim, vertical enclosure- The loudspeaker's two-piece, interlocking design makes for quick and easy setup, breakdown and transport. Creating nearly 180 degrees of horizontal coverage and consistent tonal balance. Can be used for instruments or other audio sources like DJ mixers, MP3 players, computers or DVD systems.