DAB Summary

DAB could be a good system because it is capable of delivering a very high quality audio signal.  It does offer a greater choice of stations than you would be able to receive on FM and it has a data channel which can send song titles and artist names and news and travel information which will be useful for future hand-held devices.

However, because there are too many stations crammed into the existing multiplexes, the bit rates of the majority of services have had to be reduced. Because the BBC have introduced 5 new stations onto their mutliplex the bit rates of all the BBC's stations have had to be reduced to a level that is not even as good as that provided by FM. On top of this, Radios 1 & 2 and most of the commercial stations use high levels of audio processing to increase the loudness of their station's sound, and this further degrades the already low audio quality.

Listeners to stations that are only otherwise available on AM would benefit from buying a DAB radio, but DAB sounding better than AM is hardly much to boast about...

If you listen on portables then because of the improved reception over FM then it may be worth buying a DAB radio (portables are very expensive at the time of writing though).

DAB car stereos are still quite expensive, starting at around £200, so I would put off getting a DAB car stereo until prices dropped. Also digitally-enhanced FM receivers for car CD players have been added by the likes of Pioneer (look for ones with D4Q) and Blaupunkt (DigiCeiver) which significantly improve FM reception in cars and are much cheaper than car stereos with DAB.

The problem with audio quality on DAB could easily be solved if the radio stations increased their bit rates, but the commercial radio stations don't seem to want to do this (they leave unused space on their multiplexes, when they could just as easily increase bit rates to fill up the multiplexes) and the BBC may not get any more DAB bandwidth. This would leave DAB

A better system for listening at home than DAB is receiving digital radio via satellite. This is described in more detail on the Digital Satellite (DSat) Radio page, but briefly, it is as cheap if not cheaper than a DAB radio (you don't have to pay a subscription to get the digital radio stations, see what you get without a subscription here), the bit rates on the vast majority of stations are higher than on DAB (none are lower on DSat than on DAB) and therefore the audio quality is far superior to that on DAB. For example, Radios 1-4 are all transmitted at 192kbps on satellite whereas Radios 1, 2 and 4 all use 128kbps on DAB. 

Therefore, for home listening I would recommend people to get satellite.

Introduction to Wi-Fi Internet radios