TheFonz said:
Maybe radio, especially AM, needs to abandon the "format" concept. Rather than try to program for 168 hours a week, start by programming for 4 hours on a Friday night or Saturday afternoon. I'm sure they'd be able to sell enough advertising for that. Eventually that time is going to be brokered anyway, if it isn't already. And it still gives some radio people a job, even if it is only part time. The days of people listening to radio for 10 hours a day are long gone. But like TV, people will tune in at a specific time if it's something they want to hear. Rush Limbaugh is proof of that.
AM, save small markets, is not a viable (read: you can make more money than it cost to run one) medium for music.
FMs have formats because block programming has proven itself to be ineffective. Listeners tend to think in terms of format, not programs, on FM music stations. 95.3 is the soft station, 99.1 is the rock station, etc.
Specialty shows are somewhat common on weekends... but did you know why they started? It was to make up for the lack of available talent to do local shows... in other words, a way to have a decent show and use board ops. Generally, thse shows were barter, so they were put in dayparts where it was virtually impossible to sell ads... Saturday and Sunday 7 to Midnight and Sunday morning.
Ad agencies do not buy Saturday evenings, no matter what is on or what the numbers are. They generally buy 6 AM to 7 PM, with rare exceptions. They ask for bonus (free) spots in other times.
No matter what you do in those hours you mention, you can not sell it in a competitive market (One of the stations I am with is #1 total market by nearly 2 to 1 on Saturday evening, and the show does not have any agency business and limited local direct business). Doing oldies or zither music does not matter. No revenue, no translation into other dayparts.
Those shows that sell block programming (infomercials) or do brokered shows (uncommon on major stations) in off dayparts are not going to give up the revenue of either for an unnsalable music show. And block or brokered shows give just as many jobs as some music show, probably more.
Comparing Rush, the most listened to long-form show in America, to some oldies or do-wop show is a very poor comparison. Talk radio does work more like TV, as it is talk-based (pardon the redundancy) while music radio is mood based. No point of comparison at all, ever.
By the way, people on average, never listened 10 hours a day. The average weekly listening in 1951 was 21 hours a person. Today, it is between 19 and 20 hours in the sales demos (18 to 54) so your "ten hour" observation is totally inappropriate and inaccruate to boot.