May be a silly question but when you can go to a market stall and buy a basic FM radio for £1 and at Woolies for £5 you can get a FMstereo/AM radio working from a single cell - both work effectively. Could DAB versions ever get to the same cost effectiveness or is the technology so complicated and energy inefficient that you could never get to these price / running levels?
It depends. Remember the prices of DVD players when they first came out? Part of the price was a $5 license fee charged for each player.
When the little companies in China started producing them, the cost of the license fee was so high in comparison to the cost of the unit versus what they sold it for ($45 cost, $50 price from the manufacturer), that they sued the licensing company wanting a reduction in the license fee.
Obvioulsy they got it.
If the DAB (or DRM), etc licensing fees drop to the point that it is possible to manufacture them and sell them that cheaply, then someone will find a way.
An example of that was in the 1970's I bought an FM tube tuner at a thrift shop. To have made it stereo originally would have probably doubled the price. I was able to buy a single chip stereo demuxer and make it stereo for about $2. If someone were to apply the same technology CONCEPT, i.e. making a single chip which does it all, they could sell them as cheaply as you ask.
Not at first, as someone has to pay for the R&D costs of desinging and making the first run of the chips, but afterwards.
Another question is what happens a similar technology flops? Sony had a warehouse full of AM stereo decoder chips in the mid 1980's and absoultely nothing to do with them. Someone figured out that if you used one in a shortwave radio, they would make something that costs thousands of dollars for around $400 retail.
Maybe something like it can be found that already has long since paid off its R&D costs, for example a cellular phone chip. Or a chip designed for a handheld gaming device such as the PSP?
Geoff.
-- Geoffrey S. Mendelson, Jerusalem, Israel gsm@mendelson.com N3OWJ/4X1GM
On Fri, 17 Oct 2008 08:34:05 +0000 (UTC), snipped-for-privacy@mendelson.com (Geoffrey S. Mendelson) wrote as underneath my scribble :
Thanks Geoff - useful reply - your talk on the licence fees makes a lot of sense if that is how it works - I see that there is now talk of DAB+ so presumably the clock restarts again and as long as they can keep producing worthwhile innovations that are adopted as standard every few years this will keep happening therefore the answer to my original question "will DAB ever get to the analogue level cost effectiveness" is - probably not!
To the extent that I understand it (correct me if I'm wrong), DAB operates on a different band. This means that broadcasters have to invest in another transmitter. Ouch.
The US uses an in-band system, with the digital channels multiplexed on the existing carrier. * Consequently, adding HD doesn't cost very much, so many stations have it, despite the fact that hardly anyone has receivers. (iBiquity recently ran a promotional $50 rebate to get people to buy HD products. I got the Sony XDR-F1HD tuner for $50, including shipping.) There are at least 23 FM stations in the Seattle area broadcasting HD, including Public Radio stations that (I assume) don't have a lot of free capital.
What's the point of moving to a new band for a service that's sonically inferior to what you already have? ** It's possible to design a lossless system that gives at least CD quality and doesn't gobble up huge amounts of bandwidth. Note, for example, how phone-line modems can operate at 22kbps or faster, on lines with a 5kHz bandwidth.
I should mention that the Sony XDR-F1HD tuner will revolutionize the tuner industry. It uses a Philips DSP chip that makes possible a dirt-cheap tuner that blows away multi-thousand-dollar tuners for distortion, separation, selectivity, and sensitivity. (Its only "weak" point is that the ultimate quieting, though good, is not up to the best possible. ***)
A state-of-the-art stereo FM tuner can now be added to to just about any audio product for an incremental cost of about $100. Within a few years, the separate component tuner will have largely disappeared.
** If the station is broadcasting its analog signal at the quality level it _should_ be broadcasting at, HD or DAB will _always_ be sonically inferior to analog. Some people claim that this is not always true because some stations process
*** The reviewer states that, in compensation, the XDR-F1HD does not have the background noise or grunge that mars the sound of some other analog tuners.
Just because a service is allocated one band, does not mean that it has to be allocated the same band everywhere. For example, GSM cell phones first used 900mHz so they would not interfere with 800mHz AMPS cell phones.
When the expansion band was allocated, it is around the same frequencies, called the 1800mHz band here, and the 1900mHz band. The 1800 mHz band starts lower and ends lower than the 1900, but there is a big overlap.
800mHz GSM phones came about because AT&T Wireless had D-AMPS service through out the US, so convinced Erikson to build them base stations that could be sloted into their D-AMPS systems and Nokia to build them phones.So if there is enough (perceived) money behind it, anything can be done.
The FM broadcast band outside of Japan was framed by the VHF low TV band and aircraft band. It is unlikely that the aircraft band will be moved, but outside of the US, the VHF low TV band has been all but abandoned, and it will soon be abandonded in the US.
There always have been stations broadcasting "hidden" channels on FM, and it would not take too much to make them digital. In some places there was a digital channel on the FM band transmitting GPS data to replace the part hidden by encryption. I think that was stopped during the first Gulf War when encryption on GPS data was dropped.
In the US, an FM channel is 200kHz wide, allocated on the odd multiples of 100kHz, that should be plenty for digital data. Here they are allocated on every multiple of 100kHz, which causes problems with US radios when brought here.
How much do you really need? MPEG-2 audio encoding (commonly refered to as MP3) works fine with 128k bits per second and MPEG-4 (aka AAC) encoding works just as well with 64k. It's not CD quality, but FM radio never was. A 128k AAC encoded signal would give you almost CD quality.
I hate to say it, but that's this week. If there is a market for a a better product someone will make it, or Phillps will improve the programing of the chip to make it better.
Again, I'm not sure how much it matters, the only time my home is truely quiet (electricaly or audiably) is when there is a neighborhood wide power failure. :-)
All stations process the signal. The question is how much. I remember when Deutsche Gramafone stopped producing recordings with sound over 15kHz because they could not be heard properly over the air.
Geoff.
-- Geoffrey S. Mendelson, Jerusalem, Israel gsm@mendelson.com N3OWJ/4X1GM
You "need" fidelity as least as high as analog FM is capable of, and that is a very high level of fidelity.
No, it won't.
You're arguing for the sake of arguing. The application of DSP to RF signals will revolutionize consumer products.
Highly unlikely. Why go to the extra work of filtering the recording?
That's a matter of opinion.
From:
"The quality is close to CD also at 96 kbit/s (48kbit/s/channel) for stereo."
But how long has that been going on?
From:
"The Yamaha DSP-1 was a revolutionary piece of early home theater surround sound equipment, produced in 1985"
It was a "crossover device" with an analog Dolbly surround processor, but the main unit was digital.
Because there was no need for sounds over 15kHz. Most people can't hear them, they were illegal to broadcast over FM radio and LP's (this was before CD's were thought of), had difficulty playing them.
Geoff.
-- Geoffrey S. Mendelson, Jerusalem, Israel gsm@mendelson.com N3OWJ/4X1GM
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