AM-band HD Radio bit rate

Scott Fybush
Thu Apr 2 12:19:40 EDT 2009

Dan.Strassberg wrote:
> Not counting subsidiary services (for example, whatever you call the
> DAB equivalent of RDS), how many bits per second do they squeeze into
> the AM-band HD Radio datastream? Is it 32 kbps? 

Indeed it is, using a proprietary codec.

> At the moment, I am
> listening to what is reported as a 32-kbps Web stream from WHAT (AM)
> Philadelphia. The content consists of adult standards music and
> occasional voicetracked voice. I can't imagine anyone having any
> complaints about the audio quality of what I am listening to with this
> (rather mundane) content. In other words, 32 kbps through what I'm
> assuming is a lossy CODEC seems just fine for routine suff such as
> Frank Sinatra backed by Nelson Riddle (at least as good as the best
> I've heard recently on AM) but would it cut it for classical music or
> something else intended for an audio connoisseur?

Music on AM HD can sound surprisingly good. The earlier versions of the 
codec were MUCH better with music than with talk, which is kind of 
backwards for AM. More recent installations sound pretty good even with 
talk. My local WHAM is much more listenable in HD than in its 
bandwidth-limited analog.


More information about the Boston-Radio-Interest mailing list