In article , Dave Plowman (News)
scribeth thus
In article , tony sayer
wrote:
In article , Dave Plowman (News)
scribeth thus
In article , tony sayer
wrote:
I don't supposed you've listened to that much net radio .. some
indeed is poor but some is very good...

The same applies to DAB - and FM.

To me the processing which is applied *in spades* to all the light
music stations is far more annoying than the low bit rates on DAB. I'd
rather not listen to badly set compressors pumping away.


Thats not a function of the transmission system just how broadcasters
use it!..

Perhaps that's the difference between us. I'm only interested in the sound
I hear in my room. I don't really care how it is unacceptably degraded.


That I find a really odd attitude from someone who works as a sound
recordist;?..
--
Tony Sayer

In article ,
tony sayer wrote:
Perhaps that's the difference between us. I'm only interested in the
sound I hear in my room. I don't really care how it is unacceptably
degraded.


That I find a really odd attitude from someone who works as a sound
recordist;?..

No, IMHO, the correct one. It's the end result that matters - not what
equipment is used.

--
*The severity of the itch is proportional to the reach *

Dave Plowman London SW
To e-mail, change noise into sound.

tony sayer wrote:
In article , Rob
scribeth thus
David Looser wrote:
"Rob" wrote in message
om...
Of course. In fairness the centre of the DAB 'whinge' was always that it
could have been so much better, and not that it was/is intrinsically bad.
'Better', as you seem to suggest below, can't always be detected even if
it has theoretical advantages.

Of course it could have been better, broadcasting quality is a compromise
between performance and cost, always has been. The broadcaster's aim is to
provide a quality that is "good enough" without being too expensive, both
for themselves and the buyers of receiving equipment.

The problem is that what is good enough for the bulk of the audience may not
satisfy the enthusiasts, how much cost do you impose on the system to
satisfy a small minority?

I don't know the costs of transmitting at higher quality. Presumably you
know they are prohibitive ...

Its the multiplex system where each MUX has so many bits .

Course the more bits the less services you can carry.

And bitz cost;!..

Yes. I suppose my issue is the quality/quantity thing. I will at some
point accept that people listen to/enjoy some of these radio stations.
Just not today ;-)

In the particular case of DAB I think a small improvement is justified, as
it can be done at little extra cost. But even as things are now the notion
that DAB is clearly worse than FM is challenged by some serious
commentators.

... and even if implemented, not worthwhile?

Debatable till the cows come home;!..

I'm of a view that if you do have an opportunity to provide something to
a high standard, you take it. Not everyone will appreciate it, maybe,
small price. I found the whole roll-out of DAB wrong-headed.

Rob

Dave Plowman (News) wrote:
In article ,
tony sayer wrote:
Perhaps that's the difference between us. I'm only interested in the
sound I hear in my room. I don't really care how it is unacceptably
degraded.


That I find a really odd attitude from someone who works as a sound
recordist;?..

No, IMHO, the correct one. It's the end result that matters - not what
equipment is used.


Rates of pay/unionisation/working
conditions/education-training-apprenticeships; equipment/process:
'green', efficient, effective, reliable, replicable, universal, under
review. And so on really. Tragic IMO - I'd have thought all these things
matter?

I have noticed this 'what matters is what works' has become more
pervasive, although even Labour had the sensitivity/expediency to remove
the phrase from their policy docs.

Rob

"Dave Plowman (News)" wrote in message
...
In article ,
Woody wrote:

AM radio, AFAIK, has always has an audio frequency response limit of
4KHz which means it needs an RF bandwidth of 8KHz. The station spacing
is thus set at 9KHz to (theoretically) leave a guard band between
stations. In practice for most domestic radios this is of little
consequence as it would be nigh impossible to hear two stations on
adjacent frequencies - something that would be possible on a
commercial/professional receiver with a much more closely controlled
passband.

Not so - the changes making the 9 kHz an international standard came in on
IIRC the early '70s. When R1 started up in the London area the 247 metre
transmissions had a bandwidth exceeding 12 kHz - the landline feeding that
transmitter was also wide band. With a good AM receiver the frequency
response didn't sound much different to FM when R1&2 did simulcasts.

--

Dead right! Woody has got this story back to front.

In the 1930s "HiFi" enthusiasts could, and did, spend hundreds of pounds
(equivalent to thousands at today's values) on "quality" receivers. These
sets had sideband responses reasonably flat to 12kHz or more, low distortion
detectors and push-pull output stages. Many had switchable sideband filters
for receiving "difficult" stations and switchable 9kHz notch filters. With
almost all broadcasts being live, and volume compression limited to a man
with a level control and a modulation meter could do, broadcast quality
could be very good indeed from a local station if a decent aerial was used,
much better than what was available from 78rpm records.

When Baird broadcast his 30-line TV on MW between 1930 and 1935 his
transmissions included baseband frequencies up to 13kHz.

What happened after the war was that increasing demand for MW stations lead
to them being packed together more closely, both in spectral and geographic
terms. So setmakers started to reduce the sideband responses of their sets
to minimise adjacent channel interference. By then, of course, the "quality"
brigade had moved to FM. Eventually it became apparent that all the
extended transmitted sidebands were doing was to increase interference, so
international agreements were made to limit transmitted bandwidth to 4.5kHz.

David.

In article , David Looser
wrote:


In the 1930s "HiFi" enthusiasts could, and did, spend hundreds of pounds
(equivalent to thousands at today's values) on "quality" receivers.
These sets had sideband responses reasonably flat to 12kHz or more, low
distortion detectors and push-pull output stages. Many had switchable
sideband filters for receiving "difficult" stations and switchable 9kHz
notch filters. With almost all broadcasts being live, and volume
compression limited to a man with a level control and a modulation
meter could do, broadcast quality could be very good indeed from a
local station if a decent aerial was used, much better than what was
available from 78rpm records.

Indeed. This was why the 'Armstrong' company sold a large number of models
of radio receiver chassis during the 40s and early 50s. (Many under other
names supplied as OEM items.) The idea being that at that time a good AM
radio could pick up quite a wide bandwidth signal. They were sold as high
quality chassis for those who wanted much better performance than the norm
for mass-produced radios and radiograms.

All must seem weird now... Different times, different ways.

What happened after the war was that increasing demand for MW stations
lead to them being packed together more closely, both in spectral and
geographic terms. So setmakers started to reduce the sideband responses
of their sets to minimise adjacent channel interference.

And also adding 9kHz[1] whistle notch filers. The old Armstrong 200 range
AM tuners also had a bandwidth that varied with input RF level. Wideband
when the signal was strong, narrowing down as the signal level was reduced.

[1] Or 8kHz for those regions of the world where 8kHz spacing was adopted.
9kHz isn't uniform around the world IIRC.

Slainte,

Jim

--
Change 'noise' to 'jcgl' if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

"Jim Lesurf" wrote in message
...
In article , David Looser
wrote:


In the 1930s "HiFi" enthusiasts could, and did, spend hundreds of pounds
(equivalent to thousands at today's values) on "quality" receivers.
These sets had sideband responses reasonably flat to 12kHz or more, low
distortion detectors and push-pull output stages. Many had switchable
sideband filters for receiving "difficult" stations and switchable 9kHz
notch filters. With almost all broadcasts being live, and volume
compression limited to a man with a level control and a modulation
meter could do, broadcast quality could be very good indeed from a
local station if a decent aerial was used, much better than what was
available from 78rpm records.

Indeed. This was why the 'Armstrong' company sold a large number of models
of radio receiver chassis during the 40s and early 50s. (Many under other
names supplied as OEM items.) The idea being that at that time a good AM
radio could pick up quite a wide bandwidth signal. They were sold as high
quality chassis for those who wanted much better performance than the norm
for mass-produced radios and radiograms.

All must seem weird now... Different times, different ways.

What happened after the war was that increasing demand for MW stations
lead to them being packed together more closely, both in spectral and
geographic terms. So setmakers started to reduce the sideband responses
of their sets to minimise adjacent channel interference.

And also adding 9kHz[1] whistle notch filers. The old Armstrong 200 range
AM tuners also had a bandwidth that varied with input RF level. Wideband
when the signal was strong, narrowing down as the signal level was
reduced.

[1] Or 8kHz for those regions of the world where 8kHz spacing was adopted.
9kHz isn't uniform around the world IIRC.

Slainte,

Jim

--
Change 'noise' to 'jcgl' if you wish to email me.
Electronics
http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html



A few years ago when I worked for Harris, I was given a demonstration of AM
stereo at their factory, using one of their new digital modulation AM
transmitters. The quality was excellent, when compared to the CD being
transmitted there was rather less extreme top (10kHz bandwidth only), but
that was all that was obviously missing. The test was being done in a lab,
so there was no interference, but nevertheless, it showed that there was
little wrong with AM as a method of modulation. AM in the Midwest of the USA
seems better than AM in the UK, both in terms of interference and bandwidth,
maybe their very high powers and large distances between stations helps, but
driving cross-country AM listening is quite feasible, whereas here, it's a
painful experience.

S.

--
http://audiopages.googlepages.com

Jim Lesurf wrote:
In article , David Looser
wrote:
"tony sayer" wrote in message
...
You went involved in the MP2 codec tests for the development of DAB?..

No, voice codecs only, but the principle is the same. More to the point
I know just how hard it is, and the lengths we had to go to, to
eliminate bias from listening tests.

FWIW I've now had a chance to record some mp3 streams 'broadcast' by some
of the net stations. This meant I could write the results onto a CDRW and
listen to them on some players. Have examples at 128/192/256kbps. What I've
found interesting is that the results *didn't* show that the 'higher the
bitrate the better the sound'. This was a totally uncontrolled test, so is
suspect, but it does strengthen my bias towards feeling that the way the
specific encoder is used (and the details of the sound patterns to be
encoded) can matter more that the output bitrate chosen.

Slainte,

Jim


I don't suppose it makes a great deal of difference if you record using
a lossless format, but isn't it more logical to just capture the
streamed audio?

Rob

In article ,
Rob wrote:
Dave Plowman (News) wrote:
In article ,
tony sayer wrote:
Perhaps that's the difference between us. I'm only interested in the
sound I hear in my room. I don't really care how it is unacceptably
degraded.


That I find a really odd attitude from someone who works as a sound
recordist;?..

No, IMHO, the correct one. It's the end result that matters - not what
equipment is used.


Rates of pay/unionisation/working
conditions/education-training-apprenticeships; equipment/process:
'green', efficient, effective, reliable, replicable, universal, under
review. And so on really. Tragic IMO - I'd have thought all these things
matter?

And what do they have to do with equipment?

I have noticed this 'what matters is what works' has become more
pervasive, although even Labour had the sensitivity/expediency to remove
the phrase from their policy docs.

Sigh. Perhaps I should explain again.

Those who moan about current 'DAB quality' are almost certainly listening
to pop music stations - as R3&4 have a just about adequate data rate for
the material they carry. Or at least during the times I listen to them.
And *every* pop and light music station is so heavily processed on all
wavebands that - to me - they are simply dreadful to listen to. Ones like
R2 the worst - given the amount of speech they transmit.
Of course it obviously doesn't offend others. People are not the same.

Rob

--
*(over a sketch of the titanic) "The boat sank - get over it

Dave Plowman London SW
To e-mail, change noise into sound.

In message , Jim Lesurf
writes


[1] Or 8kHz for those regions of the world where 8kHz spacing was adopted.
9kHz isn't uniform around the world IIRC.

Out of interest, which region is 8kHz? I thought it was only 9 or 10.
I've had a quick look, but can't find 8.
--
Ian