This weekend, I've noticed additional deterioration of the audio
quality on KFRC-FM, both for the main channel, repeating all-news KCBS(AM),
and for the HD-2 channel, carrying the remnants of KFRC's former
classic hits format. An HD-3 channel for KFRC now pops up.

The odd thing is that this deterioriation was noticeable even
though there was no audio on the HD-3 channel. (I could live with
the sound at HD-2 compression levels, but not at HD-3.)

Is the HD compression scheme one that allocates a fixed number of
bits to each channel, regardless of the need for those bits at any
moment in time?

One also questions the wisdom of further compromising audio quality
on a station that's all-news. The HD compression scheme really
chews up voices but can be somewhat more tolerable on music. (I
readily admit this statement is a matter of perception.)

It also appears that, at least in the San Francisco Bay Area, CBS
is being most aggressive with its HD programming. If there will be
an HD-3 channel for KFRC-FM, it will be the second station in the
Bay Area with one. The other is KCBS's KITS, running alternative on
the main channel, "classic alternative" on HD-2, and the last.fm
"discovery" channel in mono on HD-3. None of the other stations
with HD are running a third channel. From a visit to New York City
last year, I recall that use of HD-3 is more widespread there.

(NB: crossposted to ba.broadcast.moderated and
rec.radio.broadcasting. Please consider directing followups as
appropriate, depending upon whether it would be of primarily
regional interest, or of broader interest.)


--
Mark Roberts - Oakland, California
If you quote, please quote only relevant passages and not the whole article.