[Bulk] [BC] HD Radio's lack of upgrade capability

[Michael Bergman]

Rich,

> Personally, I don't want anything matrixed. I don't want a phantom 
> center or mono rear. To me 5.1 means 6 discrete channels. We're 
> already late, since 7.1 is common in home equipment.

> Are we too late to weigh in on this, too?

One proponent is MPEG SAC, which is discrete.  They obviously can't send as
much info as, say, Dolby Digital would require, but they do send discrete
info over less than 16kbps.  The jury appears to be out on how low the bit
rate requirement will be.  Neural can yield discrete effects.  Other
proponents are SRS and Dolby; Logic 7 has recently inquired as well.

Issues on all these systems are about how to prioritize the various
tradeoffs: fidelity to the source material, backwards compatibility with
analog, compatibility with existing surround equipment in cars and homes,
trained ears' evaluation of the resulting decoded audio, average consumer
evaluation of the resulting audio, how much L-R impact the system has (L-R
increase due to matrix encoding of the audio can increase multipath noise)
and how much change to the broadcaster equipment (studio, STL, etc.) is
required.

For example, matrix proponents point to the large number of receivers in the
field that have matrix compatible decoders, and that a matrix signal is
compatible with analog FM and IBOC, and that the broadcaster equipment
requires the smallest change.  Other proponents have more discrete surround
effects and do not increase L-R.

Something else to consider is the competition from surround emulation in
existing receiver systems.  For example, a Dolby ProII or SRS CS receiver
can take stereo audio and create a simulated surround environment.  

Some consumers will be happy with this result, and some will be happy with
stereo or won't splurge for the 5.1 system, so how much market is there for
"broadcast surround"--and how can we all make the public aware of and want
something like this, which is an upgrade from, say, iPod audio.

Some of the broadcasters leading the charge are Mike Pappas at KUVO, AES
Cincinnati, and NPR.  The NRSC has a study group looking at it and
monitoring these activities.

Mike Bergman