You’ve probably heard about HD Radio and D.A.B. Odds are you’ve never heard it. But it’s touted as being ‘better’ than FM. The typical bitrate for DAB programs is only 128 kbit/s and as a result most radio stations on DAB have a lower sound quality than FM, prompting a number of complaints.
An informal listening test has shown that for stationary listening the audio quality on DAB is lower than FM stereo, due to most stations using a bit rate of 128 kbit/s or less, with the MP2 audio codec, which requires 160 kbit/s to achieve perceived FM quality. 128 kbit/s gives a more smeared stereo image, and an upper cutoff frequency of 14 kHz, corresponding to 15 KHz of FM radio. CD quality audio is possible with 192 kbit/s. Still, most DAB owners (including mobile listeners) believes DAB to have equal or better sound quality than FM.Read More