A comparison of HD Radio, XM Radio and AM radio
Sunday, October 28th, 2007The following samples represent the following radio formats:
- HD-AM
- XM low bitrate talk radio
- Standard AM
- 24 kbps, KFAB, Omaha
- 24 kbps
- KFAB, Omaha
Mainly these samples exist to show what digital HD Radio sounds like on AM. Recently the FCC granted radio stations the privilege to broadcast HD-AM at night. This makes a world of difference for talk radio shows.
According to sources on the web, both HD-AM and XM Talk 165 broadcast around 24 kbps. Their audio samples do sound about the same to the ear.
The compression artifacts on both HD AM and XM radio are quite noticeable at this low bitrate. A strong AM signal on a good radio can rival the digital in overall fidelity. However, the lack of hiss, pop and fade, along with immunity from outside interference makes the digital experience more enjoyable.
About the recordings
The HD Radio recording was made using a Sangean HDR-1 connected via a standard stereo audio cable to my PC’s line-in jack. The recording was made using TotalRcorder as a full, uncompressed wave file and then saved into a 320kbps MP3.
The XM recording was made using an XM Radio Roady2 in a similar recording configuration.
The AM recording was made using a Sony boombox with an analog tuner that gets pretty fair reception and fidelity.
