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BBC Radio 3 CD player

Almost everything in broadcast is file based these days.

Amazing what sending it down the airwaves to R3 (albeit digitally) does for s.q. On Saturday afternoons, from 4 to 6 ish, there's a mix of recorded and live jazz. Detectable on my 01, but really not a lot of difference with good recorded material (presumably file-based).
 
Amazing what sending it down the airwaves to R3 (albeit digitally) does for s.q. On Saturday afternoons, from 4 to 6 ish, there's a mix of recorded and live jazz. Detectable on my 01, but really not a lot of difference with good recorded material (presumably file-based).

Sending the sound via the airwaves smooths out the rough edges of the digits.
The further you are from the transmitter the better because more of the rough edges get taken off the further the waves travel.
Surprised you didn't know that.
 
Sending the sound via the airwaves smooths out the rough edges of the digits.
The further you are from the transmitter the better because more of the rough edges get taken off the further the waves travel.
Surprised you didn't know that.

:D A eureka moment indeed ! Following your logic, if you stray out of transmission range, ALL the rough edges would be smoothed.
 
:D A eureka moment indeed ! Following your logic, if you stray out of transmission range, ALL the rough edges would be smoothed.

No, that is obviously absurd.
The optimum location is just at the limit of reception just before the signal finally fades away. At that point all of the digital rough edges have been smoothed out, and it sounds really 'analogue'. You will have seen pictures of those nasty 'staircase' digital waves.

That's why real radio enthusiasts have very big aerials, so that they can pick up the furthest possible transmitter - get it?

Some expensive radio receivers have a meter to check the signal. Some people mistakenly call these 'signal strength' meters. Actually you are searching for the weakest signal which has passed the greatest distance.
 
I may be wrong on this but sound quality of FM stations depends mostly on the dac used to play server based digital files.
 
As far as I know it only enters the analogue domain at the transmitter, having been distributed in whatever the modern version of NICAM is.
 
That's why real radio enthusiasts have very big aerials, so that they can pick up the furthest possible transmitter - get it?

A G23 on h/d rotator 40m + above street level, overlooking the English Channel and with miles of multi-strand cable etc. going back to the hifi room. I did my bit when I was younger (and radio was fully analogue).
 
Been thinking about this lately. For all the money I spend on other sources, by far the best sound I ever get is a good FM BBC broadcast . I assumed everything other than live broadcast is file based - so what kit do they use in the studio ?
 
Been thinking about this lately. For all the money I spend on other sources, by far the best sound I ever get is a good FM BBC broadcast . I assumed everything other than live broadcast is file based - so what kit do they use in the studio ?

Whatever they use, it's all transmitted over a 13 bit digital link anyway, so it's presumably more or less irrelevant.
 
Whatever they use, it's all transmitted over a 13 bit digital link anyway, so it's presumably more or less irrelevant.

Do you mean that because it is transmitted over 13 bit that it cannot be of sufficient quality to bother with?
 
Whatever they use, it's all transmitted over a 13 bit digital link anyway, so it's presumably more or less irrelevant.
Is this still true? I know it was in the past. For the digital aac stream I believe it’s 24/48 before encoding. Is this still reduced to 13:16 or whatever before fm broadcast?
 
Yes, NICAM is still used: http://www.bbc.co.uk/rd/blog/2016-01-35-million-people-didnt-notice-a-thing-dot-dot-dot

The reason it uses the lossy compression system that it does is that the quantisation noise caused by dropping some of the bits is comparable to the signal/noise ratio of FM transmission.
Sure. There was a good reason to invent the 13 bit coding when the rest of the system was analogue. Now that the front end is all digital anyway I just assumed that they might have got rid of it or unpgraded the codec.

I loved the link to the "BBC Engineering" release from 1978
http://downloads.bbc.co.uk/rd/pubs/archive/pdffiles/engineering/bbc_engineering_109.pdf
 
Mapping PCM data into NICAM should be an easy mathematical and software conversion without dropping into analog.
Never underestimate the fear of losing backwards compatibility
 
Yes, so far as I know, the BBC still use NICAM for distributing the audio for FM stereo. If anyone wants to know the details, you can find the 'history' here

http://www.audiomisc.co.uk/BBC/PCMandNICAM/History.html

as reported to me by those involved.

The 'weak link' in general remains that part from FM TX to the output of your tuner. Chances are that'll be where most distortion and noise will be added.
 


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