http://news.com.com/High-definition+radio+gears+up+for+reality/2100-1041_3-5722285.html > Hope to hear more info.
This looks like what is already available in the UK and known as DAB -
digital audio broadcasting.
Although it has the possibility of providing decent quality - although not
that of CD due to the data reduction employed - it's been implemented here
to give more choice of stations but with rather poor audio quality due to
the low data rate.
*Some days we are the flies; some days we are the windscreen.*
Dave Plowman email@example.com London SW
On Sat, 08 Oct 2005 17:43:46 -0400, Malt_Hound <""Malt_Hound\"@*spam-me
not*yahoo.com"> wrote:>Skip wrote:
Give it more than a moment of thought: digital transmission invariably
consumes narrower bandwidth than analog, given the same information. This
enables expanding the digital content to use up the same channel bandwidth as
the analog version. Hence, "higher definition".
Clues: cable companies are moving analog stations to their digital realm,
allowing the use of the bandwidth for even more digital channels...
Your statement is completely false. The reason that digital signals use
less bandwidth is not content-related. It's due to the fact that we've
quite a lot about compression technology, have radio receivers/amps
with far lower noise than tube technology, can use the time dimension
now that we have cheap volatile memory, and other various and sundry
Oh, no. *YOU* are the one with incomplete knowledge of digital and analog
coding techniques. Do you even know that digital music encoding *NEVER*
precisely reproduces the original analog music source? Do you know what
an integral is and how it works? Obviously not.
Oh dear. You seem to think that analogue recording is seamless. Magnetic
tape has a series of tiny magnets which have to be aligned to do their job.
Vinyl records are made out of particles too. So really rather similar to
the sampling rate of digital.
*The closest I ever got to a 4.0 in school was my blood alcohol content*
Dave Plowman firstname.lastname@example.org London SW
Not even remotely the same thing, Dave. There is no DAC in a phono
cartridge or pre-amp input circuit, nor in the analog tape recorder in my
Although the *result* is very close, the abstraction of digitally-encoded
data is a very different animal than analog encoding.
I want to apologize for the rather hasty reply. How about this thought
experiment. Consider a substitute for a vinyl record: take a laser and
modulate it to draw the analog waveform in a cd/dvd type medium. It's
clear (to me, and I believe to you) that such a system could very precisely
record the analog input. In fact, it would be much better than the stereo
record, because the channels wouldn't have to be intermixed into the
same groove/engraving via the encoding scheme (I can't even remember
the name right off hand it's been so long).
It's clear that a scheme like this could easily exceed the current cd for
accuracy and clarity, and would have no more noise than a current cd.
For some reason, the "daytripper" character seems to believe that
"digital" automatically mean's it better than "analog". Also, he seems
to believe that "digital radio" transmits by some magical means beyond
the physical analog world. Neither belief is true, unless everything every
physicist in the world is wrong.
Now, if you want to say that current digital and radio transmission
technology allows us to design systems that exceed the performance
of 50-75 year old analog systems, I won't argue that point. Notice,
however, that the *DESIGN* of those systems embodies assumptions
about the physical limitations of the human senses of sound and sight
to "trick" those senses. One might also note that current technology
(tv's and monitors) don't come close to the limits of what the
eye/mind can perceive, *because* of the limitations of digital display
Hey, you want to mischaracterize what I said (digital transmission of the same
source data occupies narrower bandwidth) with all your misconceptions on the
topic, fine, knock yourself out.
You can stick your degrees where the sun don't shine, they mean nothing if you
cannot think for yourself, and in any case, would easily be trumped by someone
with the degrees from actual, reputable schools *and* 35 years of digital
design, from IBM mainframes through Digital superminis to fault tolerant
non-stop servers, with over two dozen US and international patents to his
credit. That, plus an IQ that'd make you pee your pants.
Go nuts, man. But when your head is finally below ground, you really should
consider putting the shovel down...
/that daytripper character ;-)
You said: "Give it more than a moment of thought: digital transmission
consumes narrower bandwidth than analog, given the same information."
That's not what you're claiming now. And, it is true only if you make
about the requirements when rendered for human senses. If you want PRECISE
transmission of analog data, you cannot (in general) depend upon digital
Actually, it's quite amusing to read the whole conversation and see where
both of our posts - all of which are fairly imprecise and subject to
by the other side - demonstrate the problem of conversation-at-a-distance.
Which, of course, is analogous to the (necessarily) imprecise
of an analog signal after A-D and D-A conversions.
We're both right, but on different points.
After I previously replied, I thought of a much better comeback that I had
If your statement is true, how do you explain the fact that the digital
you claim carry more data than analog signals do, are themselves carried
on analog signals?
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