Tuesday, September 7, 2010

HD Radio on AM – Not worth it

HD Radio on AM – Not worth it


August 29th, 2010 by Paul Riismandel in HD Radio
 
One of the supposed advantages of HD Radio is improved fidelity over analog. As I observed in my listening test of HD on FM, there’s almost no real improvement for HD over the analog signal. The advantage for HD on FM, then, is the addition of one or two more channels of audio. However, due to the more limited sonics of analog AM radio, we are led to expect HD AM stations to offer significantly better fidelity; they don’t offer any additional channels.

But compared to FM, there are much fewer HD stations on AM. This is largely due to the fact that the AM band is seriously congested, with quite a bit of interference. Adding an HD Radio IBOC side-channel to a station greatly increases the potential for interference to adjoining analog stations. A secondary reason is that the AM band is dominated by talk radio formats where fidelity improvement is less important.