"From what I read, the only audiences for AM are Luddites like me and by our advanced age we won' t hear anything over 2k anyways..."
LOL! Fortunately it's better than that. AM actually can sound quite good without any digital "enhancements" if only TPTB would let us do it in an optimal way. Most stations are like mine--running transmitters capable of passing a full 50-15,000 hZ audio range, either in mono or C-QUAM stereo, if the Feds didn't force us to roll off the highs at 10 kHz. And if the receiver manufacturers had continued to make radios that could capture all that range and pass it through the audio amplifier stage into the speaker, you'd hear it come through just as clearly as an FM station. Some radios (including a lot of recent Delco car radios, like the one in my Chevy) actually do a pretty good job of presenting AM signals that are transmitted crisply and clearly, so it certainly can be done. IBOC actually does more harm than good, gobbling up a wider bandwidth than well-transmitted analog audio on AM while coming through little better than a phone call on most of the 99.99 per cent of us who still listen to radio on analog receivers.