In an article for the DRM Consortium, the president of JHBC Broadcast Consulting, Jochen Huber, discusses the advantages of using DRM for wide coverage transmissions.
 

Most countries in the world operate medium wave transmitters using output power of above 500kW.  The aim of the medium wave broadcast is to achieve basic radio propagation for wide range areas and to influence neighbouring countries. In several European and North African countries longwave transmitters, which are high powered above 300kW and up to 2MW, are in operational use…

A new and very interesting opportunity presents itself with the advent of the DRM standard. With DRM the broadcaster can use the large area coverage benefit given by AM transmissions and all the advantages of modern digital radio technology at a fraction of the analogue energy costs. DRM offers at least the same coverage as before with AM with sound that is free of interference and  crystal clear.  Additionally many new features such as Journaline or Emergency Warning are available….

Read the full article here.