I was just flipping through the stations on my DAB the other day, and was
struck by an underlying grotty feel to many stations. I am speaking of the
gritty sound that many, most often talk stations, Have now. Talk radio, to
pick one at random, sounds like one of the lower quality long play modes on
a minidisc. AM was better in my view, assuming you were close to the
transmitter. I'm just guessing that it is part of a reduction in bitrate or
increase in errors inherent in the system.
Even music stations, be they plus or otherwise are not totally immune, but
then I have no way to know what sort of encoding is in use.This distortion
though, seems to also affect other outlets of the same station, as if they
are all distributed in the worst possible system.

I just can't listen to the talk stations any more due to this gritiness.
However its worse I think if you are an ethnic minority, as their stations
even try to play music over it as well. Bah humbug.
Brian

--

--:
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The Sofa of Brian Gaff...
briang1@blueyonder.co.uk
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Note this Signature is meaningless.!

Don't get caught out Brian. Talk Radio (and for that matter GB News
Radio) is DAB+ (DAB PLUS) but at different rates. Talk is 32 kilobits in
stereo, GB News is 24 kilobits mono.

I have also noted that both stations (although more noticeably GB News)
seem to have some sort of muting system so that there is no noise
between speakers or between separate bits of the same speaker. It often
results in loss of the first syllable when the speaker starts talking
and the mute or whatever it is seems to have a relatively slow attack.

I don't notice any issues with grittiness as you report it, but could I
suggest that it may be something to do with distribution? We out here in
the frozen north seem to get clear quality - perhaps there is just too
much infrastructure or distribution noise in London?

On Sun 28/01/2024 17:26, Brian Gaff wrote:
> I was just flipping through the stations on my DAB the other day, and was
> struck by an underlying grotty feel to many stations. I am speaking of the
> gritty sound that many, most often talk stations, Have now. Talk radio, to
> pick one at random, sounds like one of the lower quality long play modes on
> a minidisc. AM was better in my view, assuming you were close to the
> transmitter. I'm just guessing that it is part of a reduction in bitrate or
> increase in errors inherent in the system.
> Even music stations, be they plus or otherwise are not totally immune, but
> then I have no way to know what sort of encoding is in use.This distortion
> though, seems to also affect other outlets of the same station, as if they
> are all distributed in the worst possible system.
>
> I just can't listen to the talk stations any more due to this gritiness.
> However its worse I think if you are an ethnic minority, as their stations
> even try to play music over it as well. Bah humbug.
> Brian
>

On 28/01/2024 20:22, Woody wrote:
>
> I don't notice any issues with grittiness as you report it, but could I
> suggest that it may be something to do with distribution? We out here in
> the frozen north seem to get clear quality - perhaps there is just too
> much infrastructure or distribution noise in London?

I can't imagine the distribution degrading the quality?

On 28/01/2024 20:28, JMB99 wrote:
> On 28/01/2024 20:22, Woody wrote:
>>
>> I don't notice any issues with grittiness as you report it, but could
>> I suggest that it may be something to do with distribution? We out
>> here in the frozen north seem to get clear quality - perhaps there is
>> just too much infrastructure or distribution noise in London?
>
>
> I can't imagine the distribution degrading the quality?
>
>
Of course it doesn't, and the stations are encoded and muxed together
centrally. So the quality is exactly the same whether you're using
Crystal Palace or Bressay.

It has to be that way, because muxes are SFNs

On 29/01/2024 12:15, Mark Carver wrote:
> On 28/01/2024 20:28, JMB99 wrote:

>> I can't imagine the distribution degrading the quality?
>>
>>
> Of course it doesn't, and the stations are encoded and muxed together
> centrally. So the quality is exactly the same whether you're using
> Crystal Palace or Bressay.
>
> It has to be that way, because muxes are SFNs

Do all the stations use the same bit rate on all the transmitters?

I can see no technical reason for that to be the case, and in Brian
Gaff's area, there is a lot more demand for setting up a station than
there is here in the Black Country, which gives an excuse for dropping
the bit rates there.

It may also be the case that Brian has more sensitivity to audio
artifacts than many sighted people.

--
Tciao for Now!

John.

On 29/01/2024 13:00, John Williamson wrote:
> On 29/01/2024 12:15, Mark Carver wrote:
>> On 28/01/2024 20:28, JMB99 wrote:
>
>>> I can't imagine the distribution degrading the quality?
>>>
>>>
>> Of course it doesn't, and the stations are encoded and muxed together
>> centrally. So the quality is exactly the same whether you're using
>> Crystal Palace or Bressay.
>>
>> It has to be that way, because muxes are SFNs
>
> Do all the stations use the same bit rate on all the transmitters?

The same bit rate has to be used on all transmitters that carry the same
mux. In fact the entire encoded transport stream has to be IDENTICAL on
all transmitters, or else the SFN won't work.

If you're taking about the same station on different local muxes, then
that's a different matter, although taking a quick look on Wohnort, even
then the bit rates are the same (probably because the station only wants
to encode itself 'once')

In message <l1pj7aFu98cU1@mid.individual.net> at Mon, 29 Jan 2024
12:15:30, Mark Carver <mark@invalid.com> writes
>On 28/01/2024 20:28, JMB99 wrote:
>> On 28/01/2024 20:22, Woody wrote:
>>>
>>> I don't notice any issues with grittiness as you report it, but
>>>could I suggest that it may be something to do with distribution? We
>>>out here in the frozen north seem to get clear quality - perhaps
>>>there is just too much infrastructure or distribution noise in London?
>> I can't imagine the distribution degrading the quality?
>>
>Of course it doesn't, and the stations are encoded and muxed together
>centrally. So the quality is exactly the same whether you're using
>Crystal Palace or Bressay.
>
>It has to be that way, because muxes are SFNs

By "distribution noise", I think Woody meant noise from _other_
distribution networks - such as the mains electricity supply - rather
than the one the listener is trying to receive. In other words, signal
degradation, not coding errors in the first place.
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

I'm too lazy to have a bigger ego. - James May, RT 2016/1/23-29

On 20:22 28 Jan 2024, Woody said:
>
> Don't get caught out Brian. Talk Radio (and for that matter GB News
> Radio) is DAB+ (DAB PLUS) but at different rates. Talk is 32 kilobits
> in stereo, GB News is 24 kilobits mono.
>
> I have also noted that both stations (although more noticeably GB
> News) seem to have some sort of muting system so that there is no
> noise between speakers or between separate bits of the same speaker.
> It often results in loss of the first syllable when the speaker starts
> talking and the mute or whatever it is seems to have a relatively slow
> attack.

My bete noir is the very rapid speech on GB News, and to a lesser extent on
TalkRadio. It certainly makes you pay close attention if you want to follow
the discussion!

> I don't notice any issues with grittiness as you report it, but could
> I suggest that it may be something to do with distribution? We out
> here in the frozen north seem to get clear quality - perhaps there is
> just too much infrastructure or distribution noise in London?

On 17:26 28 Jan 2024, Brian Gaff said:
>
> I was just flipping through the stations on my DAB the other day, and
> was struck by an underlying grotty feel to many stations. I am
> speaking of the gritty sound that many, most often talk stations, Have
> now. Talk radio, to pick one at random, sounds like one of the lower
> quality long play modes on a minidisc. AM was better in my view,
> assuming you were close to the transmitter. I'm just guessing that it
> is part of a reduction in bitrate or increase in errors inherent in
> the system.
>
> Even music stations, be they plus or otherwise are not totally immune,
> but then I have no way to know what sort of encoding is in use.This
> distortion though, seems to also affect other outlets of the same
> station, as if they are all distributed in the worst possible system.
>
> I just can't listen to the talk stations any more due to this
> gritiness.
>
> However its worse I think if you are an ethnic minority, as their
> stations even try to play music over it as well. Bah humbug.
> Brian

Years before DAB, I was complaining how radio stations were sounding
distinctly distorted. However it turned out to be some unusual damage to
my hearing from an infection.

On 29/01/2024 18:08, Pamela wrote:
> I have also noted that both stations (although more noticeably GB
> News) seem to have some sort of muting system so that there is no
> noise between speakers or between separate bits of the same speaker.
> It often results in loss of the first syllable when the speaker starts
> talking and the mute or whatever it is seems to have a relatively slow
> attack.

Isn't that common with automated presenter operated sources?

In message <upa7dn$t0j9$1@dont-email.me> at Tue, 30 Jan 2024 07:10:47,
JMB99 <mb@nospam.net> writes
>On 29/01/2024 18:08, Pamela wrote:
>> I have also noted that both stations (although more noticeably GB
>> News) seem to have some sort of muting system so that there is no
>> noise between speakers or between separate bits of the same speaker.
>> It often results in loss of the first syllable when the speaker starts
>> talking and the mute or whatever it is seems to have a relatively slow
>> attack.
>
>
>
>Isn't that common with automated presenter operated sources?
>
>
AGC to mute background noise when the speaker is not speaking has been
around for decades; however, you'd think that today it would be trivial
to insert a slight delay - half a second ought to be more than enough in
most cases - so that the chopping-off-of-the-first-syllable that Pamela
has noticed could be avoided. Could be either at the presenter end or
the studio end. But obviously isn't being done.
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

"Grammar is there to help, not hinder."
-- Mark Wallace, APIHNA, 2nd December 2000 (quoted by John Flynn 2000-12-6)

Yes that can happen. I have tinnitus, but that was from being too close to a
couple of lightening strikes in my 30s. It does not impact the definite
grainy feel of the sound. Its a bit like its been recorded on a very bad
tape, you know the sort usually sold at markets.
My guess is its the half sample rate issue you can get on low bit rate
mp3s. These also affect phase between channels too, since they try to make
it sound right on smaller systems.
Brian

--

--:
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...
briang1@blueyonder.co.uk
Blind user, so no pictures please
Note this Signature is meaningless.!
"Pamela" <pamela.private.mailbox@gmail.com> wrote in message
news:XnsB108B8FD418565D4AM2@135.181.20.170...
> On 17:26 28 Jan 2024, Brian Gaff said:
>>
>> I was just flipping through the stations on my DAB the other day, and
>> was struck by an underlying grotty feel to many stations. I am
>> speaking of the gritty sound that many, most often talk stations, Have
>> now. Talk radio, to pick one at random, sounds like one of the lower
>> quality long play modes on a minidisc. AM was better in my view,
>> assuming you were close to the transmitter. I'm just guessing that it
>> is part of a reduction in bitrate or increase in errors inherent in
>> the system.
>>
>> Even music stations, be they plus or otherwise are not totally immune,
>> but then I have no way to know what sort of encoding is in use.This
>> distortion though, seems to also affect other outlets of the same
>> station, as if they are all distributed in the worst possible system.
>>
>> I just can't listen to the talk stations any more due to this
>> gritiness.
>>
>> However its worse I think if you are an ethnic minority, as their
>> stations even try to play music over it as well. Bah humbug.
>> Brian
>
> Years before DAB, I was complaining how radio stations were sounding
> distinctly distorted. However it turned out to be some unusual damage to
> my hearing from an infection.
>

On Mon, 29 Jan 2024 13:18:01 +0000, Mark Carver <mark@invalid.com>
wrote:

>On 29/01/2024 13:00, John Williamson wrote:
>> On 29/01/2024 12:15, Mark Carver wrote:
>>> On 28/01/2024 20:28, JMB99 wrote:
>>
>>>> I can't imagine the distribution degrading the quality?
>>>>
>>>>
>>> Of course it doesn't, and the stations are encoded and muxed together
>>> centrally. So the quality is exactly the same whether you're using
>>> Crystal Palace or Bressay.
>>>
>>> It has to be that way, because muxes are SFNs
>>
>> Do all the stations use the same bit rate on all the transmitters?
>
>The same bit rate has to be used on all transmitters that carry the same
>mux. In fact the entire encoded transport stream has to be IDENTICAL on
>all transmitters, or else the SFN won't work.
>
>If you're taking about the same station on different local muxes, then
>that's a different matter, although taking a quick look on Wohnort, even
>then the bit rates are the same (probably because the station only wants
>to encode itself 'once')
>
Until very recently Gold in London was 40 kbps and Gold UK was 32
kbps. Now they seem to be equalised.

On 11:10 30 Jan 2024, J. P. Gilliver said:
> In message <upa7dn$t0j9$1@dont-email.me> at Tue, 30 Jan 2024 07:10:47,
> JMB99 <mb@nospam.net> writes
>>On 29/01/2024 18:08, Pamela wrote:
>>>
>>> I have also noted that both stations (although more noticeably GB
>>> News) seem to have some sort of muting system so that there is no
>>> noise between speakers or between separate bits of the same speaker.
>>> It often results in loss of the first syllable when the speaker starts
>>> talking and the mute or whatever it is seems to have a relatively slow
>>> attack.
>>
>>Isn't that common with automated presenter operated sources?
>>
>>
> AGC to mute background noise when the speaker is not speaking has been
> around for decades; however, you'd think that today it would be trivial
> to insert a slight delay - half a second ought to be more than enough in
> most cases - so that the chopping-off-of-the-first-syllable that Pamela
> has noticed could be avoided. Could be either at the presenter end or
> the studio end. But obviously isn't being done.

Woody said that, not me. It was attrubuted incorrectly.

"J. P. Gilliver" <G6JPG@255soft.uk> wrote in message
news:S7+ukbbjkNulFwOv@255soft.uk...
> In message <upa7dn$t0j9$1@dont-email.me> at Tue, 30 Jan 2024 07:10:47,
> JMB99 <mb@nospam.net> writes
>>On 29/01/2024 18:08, Pamela wrote:
>>> I have also noted that both stations (although more noticeably GB
>>> News) seem to have some sort of muting system so that there is no
>>> noise between speakers or between separate bits of the same speaker.
>>> It often results in loss of the first syllable when the speaker starts
>>> talking and the mute or whatever it is seems to have a relatively slow
>>> attack.
>>
>>
>>
>>Isn't that common with automated presenter operated sources?
>>
>>
> AGC to mute background noise when the speaker is not speaking has been
> around for decades; however, you'd think that today it would be trivial to
> insert a slight delay - half a second ought to be more than enough in most
> cases - so that the chopping-off-of-the-first-syllable that Pamela has
> noticed could be avoided. Could be either at the presenter end or the
> studio end. But obviously isn't being done.

Almost as bad is when AGC mutes significant background noise in a drama,
where the noise is ambient sound (eg birdsong, traffic noise) which is
*wanted* to give atmosphere. There is an episode of Inspector Morse that was
fine on its original ITV broadcast but every time it is shown on ITV3 the
sound is very poor (maybe ITV3's copy was badly copied from the master) and
the background noise in some exterior scenes pulsates every time anyone
speaks - you see the characters walking along talking, and there is absolute
silence except when someone speaks when you suddenly get a blast of birdsong
as well which is not there when no-one is talking - very unnerving.