DAB is Mp2, an older lossy format. It is relatively inefficient so 160Kb Mp2 (Radio 3) is about the same quality as 128Kb Mp3. The other programmes are less than 160 so draw your own conclusion. CD is a lossless digital signal (if there is such a thing!) and should be as near as possible the same quality as the original signal. There was a claim made during early DAB PR campaigns that DAB was effectively the same quality as CD. I believe they were reprimanded for that claim because DAB/Mp2 is inferior to CD. In so saying, with a good signal and decent digital to audio conversion DAB can sound very respectable. However it will still be knocked into a cocked hat by DVB radio and FM.