On Sep 29, 7:22 pm, SFTV_troy wrote:
Tom wrote:

...So, too, does DRM benefit from said development, making it
possible to provide a digital carrier within LW,MW and SW channeling
plans. Thast said, I find it much less fatiguing to listen to a
program on an analog AM carrier than to the same program over DRM.

I've never heard DRM. How does it sound, and why is it "fatiguing" to
hear?

DAB...because of a concerted government, broadcaster and
manufacturing industry push, the likes of which we have not seen in
other countries. A stronger parallel can be drawn to the sizable
takeup of XMRadio and Sirius satellite services in the US and Canada -
the quality stinks but the program choice and wide ranging coverage
are unique.

The quality stinks? Really? I listen to XM streams via the internet,
and they sound just fine. Is there really that huge of a difference
between Internet and Mobile Receiver?

I've been more impressed by synchronous AM demodulation of AM signals
than by a digital equivalent. It's a pity we could not get mass
manufacturing of synch AM radios and ultimately convert all AM
stations to USB with reduced carrier for power savings and reduced
interference.

What's USB? What's synchronous AM demodulation? Thanks.

Earl answered the last question really well.

DRM (and I imagine HDradio-IBOC-AM) are fatiguing (to some people)
because very low audio encoding bitrates must be employed in order to
fit within the allowed spectrum; typically 10kHz of RF spectrum
restricts the audio to perhaps 20kbps. Considering that a CD streams
at about 75 times this rate, losses in encoding at these very low bit
rates along with the consequent artefacts are pretty severe. Low
bitrate audio tends to have a gurgling, grainy, grungy effect - hard
to describe but after a while, I just have to turn it off. Admittedly,
ambient noise (e.g. road noise) can mask a lot of it but I'm not sure
that it's any less fatiguing.

I was too general in my comment about satellite radio. Both XM and
Sirius use a range of encoding standards, putting news/talk on the
lowest and music on the highest. My main channel on Sirius Canada is
CBC Radio One which was stupidly assigned a news/talk standard when it
actually comprises an eclectic mix of content - we're currently
listening to Randy Bachman (BTO) playing #2 hits from the 60's and
70's in his weekly 3-hour program from the local FM. The Sirius news/
talk encoding is not much higher than 20kbps - voice is bad enough but
music really stinks. The highest standards on XM and Sirius are
better, but like Eureka DAB, frozen in quality at that which could be
provided by the adopted codecs of the day (1990's). What you hear over
the Internet will be encoded differently, using codecs popular for
Internet streaming, not their proprietary ones for satellite delivery.
Both XM and Sirius favour offering more choice than higher quality,
so, like Eureka DAB, subdivide their digital channel capacity into
more, smaller chunks - maybe that's what sells subscriptions - ergo,
lower quality.

Tom