Ebbw Vale, South Wales - Jul 20, 2011 - The introduction of a new station in South Wales illuminates an interesting feature of the DAB Multiplex transmission scheme used throughout England: The ease with which the multiplex operator can reallocate the available data bandwidth, thus creating room for another station or stations.
Ofcom (England's equivalent of the FCC) provides a form upon which changes are requested. One such example can be seen here. In this case, Mountain FM, previously only heard by way of the Internet, can now be heard on the MXR South Wales and Severn Estuary Multiplex. As you can see from the Ofcom document, Rock Radio went from a 128kb/s data stream (stereo) down to an 80kbps /mono stream; at the same time, RealRadio went from 128kb/s down to 112kb/s (stereo) thus freeing 64kb/s (mono) for Mountain FM. Another example is a subsequent change for Nation Radio. (Read that particular Ofcom document.) Nation went from 128kb/s stereo down to 64kb/s mono, thus freeing 64kb/s for a new service known as Bay Radio.