In article ,
Mark Roberts wrote:

On a synchronous detector, it sounds worse...like a mosquito buzzing
in the background.

That's because it's in quadrature, which is "invisible" (modulo
transmission artifacts and channel noise) to envelope detectors. Your
sync. detector is only detecting one sideband at a time, so the IBOC
carriers don't cancel out.

(This is why I no longer listen to WBZ much during the daytime.)

None of the engineers I've talked to like the AM system. Some of them
see it as having potential to bring back a long-lost audience, in
spite of its significant flaws. Most of them see it as a pointless
corporate mandate that will waste their engineering budgets, reduce
their coverage areas, and dirty up their audio chains.

People I talk to in *my* business (computing, not broadcasting) are of
the opinion that traditional, reserved-spectrum broadcasting will
cease to exist inside of three decades, for various reasons, social as
well as technological. (That's assuming it isn't already dead -- many
of the people I know, my age and younger, are simply no longer users
of radio at all. It doesn't connect with them in any meaningful way,
nor does it serve their needs.)

-GAWollman

--
Garrett A. Wollman | As the Constitution endures, persons in every
| generation can invoke its principles in their own
Opinions not those of| search for greater freedom.
MIT, LCS, CRS, or NSA| - A. Kennedy, Lawrence v. Texas, 539 U.S. ___ (2003)