As far as our *broadcast* spectrum is concerned, the FCC blew it by allowing companies such as EMF to drop in K-Love frequencies all over the land. Many markets have K-Love on as many as 6 FM channels. This carpetbaombing is flat-out wrong, and a real stretch of FCC rules (if they haven't been overturned while I speak). Then, they wonder why people are PO'ed about interference on FM. Then, why do they not extend the band down to 76MHz? I'm sure "well nobody has radios for that band". Okay, I'll buy that. However, some of the same voices stating that argument are the ones pushing for sunset of analog and full IBOC. Wait!! There are so few radios around! Did you just not contradict your concern for "no radios"
And should I even mention the handling of analog TV sunset??? People are STILL having issues receiving many of their favorite OTA signals.
Then, there is AM band. IMO, a LOT of these broom-closet automation trainwrecks *need* to go dark. How many AM signals does a market need with evangelists or hate-talk? I could hear Rush on NO LESS than 8 signals, all of which come in clear, in Flint. There is duplicate sports-talk on FOUR signals. To me, this is a waste. Granted, I'm an old-school radio guy who has despised automation since the days of Drake-Chenault reels.
One reason for so many duplicate signals on the AM band is skywave propagation (at night) and -- more recently -- RFI (24/7).
AM broadcasters are dealing with an increased noise floor from RFI broadcasting devices, and the coverage patterns of the 1960's do not cover the same area with noise-free reception in 2019. Hence, when there is a network (like a sports network, for example), they will use a main station and perhaps a rimshot or two. As Sports radio networks do not primarily rely on ratings the way music radio does, the multiple stations in a region can work. There are competing sports networks, but the number has declined since earlier in the decade.
HD on AM can work in some situations, and there are receivers already out there -- mostly in cars. There are much less numbers of FM receivers that go down to 76 MHz, and in the US that spectrum apparently is allocated for other services. I agree that the government could open it up and see what flies, but that ship might have already sailed as younger demos use streaming more and more.
As for your question "How many AM signals does a market need with evangelists or hate-talk?" you could say the same for
any radio format. How many AC or pop stations does a market need? How many NPR outlets does a metro need? Some markets have more than one. Apparently the market will support it, so they make a go of it. And as for EMF, in my metro there is a KLove and an Air1 (rimshot FM) and that's it. My entire state has only 8 or 9 EMF stations, and they are widely placed, low power stations.
The fact is, all radio station owners make their format and marketing decisions based on what will support the station and keep it on the air, and hopefully make some money.
As for the AM broadcasting quality issue, I think a lot of it is low revenue, and the NAB standards (limiting of audio bandwidth) that happened back in the 1980's didn't help things much. The revenue issue has only added to the audio issues.