 DAB has also been marketed as having two major advantages over analogue radio broadcasting in that using MPEG @-@ 1 Audio Layer II lossy audio compression technology , parts of the audio spectrum that cannot be heard by humans are discarded , meaning less data needs to be sent over the air . This , as well as multiplexing technology , allows a number of channels to be broadcast together on one frequency as opposed to one channel for analogue radio broadcasts . 
