One of the biggest favorites of HD Radio is the HD2 and HD3 channels. Each radio station that broadcast in HD have the ability to have multiple channels, and they are adding twist on how they utilize these extra channels. All you need to listen to HD Radio is a capable receiver. There are no subscription fees or additional add on fees, once you have a radio or device that can receive in HD, it is all yours.
Traditional radio broadcast in analog, HD Radio converts analog to a digital signal and offers advanced audio and data features. Radio signals bounce off of objects as they are broadcast which is what gives conventional radio the distortion that you are used to hearing. What HD Radio does is eliminate all the reflected signals, static and distortion so that way when it reaches your tuner you hear a crystal clear audio.