The number of bands refers to the number of frequency bands that the loudspeaker or system reproduces. A single-band loudspeaker produces all the sounds from a single transducer, while a multi-band loudspeaker has multiple transducers, each optimised for a specific frequency range (e.g. high, mid, low frequencies). Multiband systems often provide better sound quality because each band can be reproduced by a transducer designed specifically for that frequency range.