On 19/06/2023 14:22, JNugent wrote:
> Adobe Audition (or even predecessor app Cool Edit Pro, if your PC will
> run it still) has excellent vinyl restoration tools within it.

I've used Audition.

On some LPs by the time I've filtered out the noise it had an
appreciable effect on the sound, filtering out some of the higher
frequencies. I ended up putting up with the hiss rumble and clicks.

Incidentally I am beginning to go deaf, so I'm sure I don't hear all the
problems!

Andy

On 20/06/2023 11:53 am, Vir Campestris wrote:

> On 19/06/2023 14:22, JNugent wrote:

>> Adobe Audition (or even predecessor app Cool Edit Pro, if your PC will
>> run it still) has excellent vinyl restoration tools within it.
>
> I've used Audition.
>
> On some LPs by the time I've filtered out the noise it had an
> appreciable effect on the sound, filtering out some of the higher
> frequencies. I ended up putting up with the hiss rumble and clicks.
>
> Incidentally I am beginning to go deaf, so I'm sure I don't hear all the
> problems!
>
> Andy

Using the click-removal facility (whether automated or manual) doesn't
affect general noise.

There's a separate facility for that (good for recording which have come
from cassette tape).

On Monday, 19 June 2023 at 14:23:01 UTC+1, JNugent wrote:
> On 07/06/2023 10:12 pm, NY wrote:
SNIP
> My earliest exposure (other than it being mentioned in print) was that
> edition of "Tomorrow's World". The presenter (can't remember who) said
> to camera that viewers ought to be able to hear the difference between
> vinyl and CD versions over the air. Whether I did or not is something I
> don't recall, but it is easy to kid yourself in these circumstances.

but if you re-read my post about doing this on FM [Signal] radio driving along the M6 ~1986, I was easily able to tell which were vinyl and which CD within a few seconds and BEFORE they announced it. This was despite the radio segment and the road, wind and engine noise in the car.

Rarely wrong, usually CD's made from poor masters (e.g. anything by the Doors).

SNIP

On 20/06/2023 12:46 pm, R. Mark Clayton wrote:

> On Monday, 19 June 2023 at 14:23:01 UTC+1, JNugent wrote:

>> On 07/06/2023 10:12 pm, NY wrote:

> SNIP

>> My earliest exposure (other than it being mentioned in print) was that
>> edition of "Tomorrow's World". The presenter (can't remember who) said
>> to camera that viewers ought to be able to hear the difference between
>> vinyl and CD versions over the air. Whether I did or not is something I
>> don't recall, but it is easy to kid yourself in these circumstances.

> but if you re-read my post about doing this on FM [Signal] radio driving along the M6 ~1986, I was easily able to tell which were vinyl and which CD within a few seconds and BEFORE they announced it. This was despite the radio segment and the road, wind and engine noise in the car.

FM stereo had the reputation of being the most hi-fi transmission
system. Hearing vinyl groove noise and clicks over that medium wasn't
unusual, especially if a worn record was being played. Especially the
very prominent tape noise on 10cc's "I'm Not In Love".

Mono TV was a different proposition, I'd say.

I wasn't saying that I could or couldn't hear a difference between vinyl
and CD when played over the air on TV - I was saying that I can't
remember whether I did!

> Rarely wrong, usually CD's made from poor masters (e.g. anything by the Doors).

People used to say that about various specific CDs. Although I can't
remember whether it was a good example or a bad example, the one that
springs to mind is Dire Straits. There was some controversy about them,
but what it was has now slipped my memory. I only ever liked one of
their songs anyway.

On Tuesday, 20 June 2023 at 13:18:04 UTC+1, JNugent wrote:
> On 20/06/2023 12:46 pm, R. Mark Clayton wrote:
>
> > On Monday, 19 June 2023 at 14:23:01 UTC+1, JNugent wrote:
>
> >> On 07/06/2023 10:12 pm, NY wrote:
>
> > SNIP
>
> >> My earliest exposure (other than it being mentioned in print) was that
> >> edition of "Tomorrow's World". The presenter (can't remember who) said
> >> to camera that viewers ought to be able to hear the difference between
> >> vinyl and CD versions over the air. Whether I did or not is something I
> >> don't recall, but it is easy to kid yourself in these circumstances.
>
> > but if you re-read my post about doing this on FM [Signal] radio driving along the M6 ~1986, I was easily able to tell which were vinyl and which CD within a few seconds and BEFORE they announced it. This was despite the radio segment and the road, wind and engine noise in the car.
> FM stereo had the reputation of being the most hi-fi transmission
> system. Hearing vinyl groove noise and clicks over that medium wasn't
> unusual, especially if a worn record was being played. Especially the
> very prominent tape noise on 10cc's "I'm Not In Love".
>
> Mono TV was a different proposition, I'd say.

Indeed, although reasonable [mono] with a decent receiver. Ni-cam was quite close to FM played through an external system.

>
> I wasn't saying that I could or couldn't hear a difference between vinyl
> and CD when played over the air on TV - I was saying that I can't
> remember whether I did!
> > Rarely wrong, usually CD's made from poor masters (e.g. anything by the Doors).
> People used to say that about various specific CDs. Although I can't
> remember whether it was a good example or a bad example, the one that
> springs to mind is Dire Straits. There was some controversy about them,
> but what it was has now slipped my memory. I only ever liked one of
> their songs anyway.

The sonic quality of Doors recordings was dire, even on vinyl.

"R. Mark Clayton" <notyalckram@gmail.com> wrote in message
news:6a9d7bcb-2ba4-42c5-99a9-a6f83d0b7299n@googlegroups.com...
> Indeed, although reasonable [mono] with a decent receiver. Ni-cam was
> quite close to FM played through an external system.

NICAM sounded better than FM, close to CD. FM was good, but I never heard a
stereo FM radio that didn't have at least *some* hiss - and the dreaded
intrusive sibilance on female newsreaders' voices.

On Thu, 22 Jun 2023 19:25:58 +0100, "NY" <me@privacy.invalid> wrote:

>"R. Mark Clayton" <notyalckram@gmail.com> wrote in message
>news:6a9d7bcb-2ba4-42c5-99a9-a6f83d0b7299n@googlegroups.com...
>> Indeed, although reasonable [mono] with a decent receiver. Ni-cam was
>> quite close to FM played through an external system.
>
>NICAM sounded better than FM, close to CD. FM was good, but I never heard a
>stereo FM radio that didn't have at least *some* hiss - and the dreaded
>intrusive sibilance on female newsreaders' voices.

I built a NICAM receiver from a Maplin kit, and it had a switch to
select FM or NICAM. On a mono broadcast, the only difference I could
hear was an increase in background hiss when I switched to FM.
Otherwise they sounded identical.

Rod.

On 22/06/2023 20:47, Roderick Stewart wrote:
> On Thu, 22 Jun 2023 19:25:58 +0100, "NY" <me@privacy.invalid> wrote:
>
>> "R. Mark Clayton" <notyalckram@gmail.com> wrote in message
>> news:6a9d7bcb-2ba4-42c5-99a9-a6f83d0b7299n@googlegroups.com...
>>> Indeed, although reasonable [mono] with a decent receiver. Ni-cam was
>>> quite close to FM played through an external system.
>>
>> NICAM sounded better than FM, close to CD. FM was good, but I never heard a
>> stereo FM radio that didn't have at least *some* hiss - and the dreaded
>> intrusive sibilance on female newsreaders' voices.
>
> I built a NICAM receiver from a Maplin kit, and it had a switch to
> select FM or NICAM. On a mono broadcast, the only difference I could
> hear was an increase in background hiss when I switched to FM.
> Otherwise they sounded identical.

My Panasonic video recorder had an option to switch its audio output
(from its phono sockets) between NICAM and FM for off-air, and between
linear and hifi soundtracks for off-tape. Switching between NICAM/FM was
very similar, as you say. My comments about the extra hiss of FM mainly
relate to the additional hiss of pilot-tone FM stereo compared with mono.

On Thu, 22 Jun 2023 23:56:51 +0100, NY <me@privacy.net> wrote:

>On 22/06/2023 20:47, Roderick Stewart wrote:
>> On Thu, 22 Jun 2023 19:25:58 +0100, "NY" <me@privacy.invalid> wrote:
>>
>>> "R. Mark Clayton" <notyalckram@gmail.com> wrote in message
>>> news:6a9d7bcb-2ba4-42c5-99a9-a6f83d0b7299n@googlegroups.com...
>>>> Indeed, although reasonable [mono] with a decent receiver. Ni-cam was
>>>> quite close to FM played through an external system.
>>>
>>> NICAM sounded better than FM, close to CD. FM was good, but I never heard a
>>> stereo FM radio that didn't have at least *some* hiss - and the dreaded
>>> intrusive sibilance on female newsreaders' voices.
>>
>> I built a NICAM receiver from a Maplin kit, and it had a switch to
>> select FM or NICAM. On a mono broadcast, the only difference I could
>> hear was an increase in background hiss when I switched to FM.
>> Otherwise they sounded identical.
>
>My Panasonic video recorder had an option to switch its audio output
>(from its phono sockets) between NICAM and FM for off-air, and between
>linear and hifi soundtracks for off-tape. Switching between NICAM/FM was
>very similar, as you say. My comments about the extra hiss of FM mainly
>relate to the additional hiss of pilot-tone FM stereo compared with mono.

The FM sound I was referring to was analogue television sound, which
never used a pilot tone because it was never stereo. The switch on my
Maplin receiver allowed me to compare the same sound from the same
source but conveyed by different methods.

The hiss wasn't loud but it was there. At normal listening levels it
wasn't annoying, as it was simply what we'd all been used to since the
start of 625/50 broadcasting. But turn the volume up and switch
between NICAM and FM and it was clearly present, but only on FM. It
just sounded like a white noise generator being switched on and off
with everything else remaining the same.

Rod.

On Friday, 23 June 2023 at 08:50:50 UTC+1, Roderick Stewart wrote:
> On Thu, 22 Jun 2023 23:56:51 +0100, NY <m...@privacy.net> wrote:
>
SNIP
> The hiss wasn't loud but it was there. At normal listening levels it
> wasn't annoying, as it was simply what we'd all been used to since the
> start of 625/50 broadcasting. But turn the volume up and switch
> between NICAM and FM and it was clearly present, but only on FM. It
> just sounded like a white noise generator being switched on and off
> with everything else remaining the same.
>
> Rod.

Indeed the hiss was there on stereo FM, however it was is some way inversely proportional to the received signal strength. On a remote [weak] station the hiss was quite intrusive, whereas on a good signal barely discernable, usually in quieter passages.

This made it worthwhile to erect a decent aerial. I took Bill Wright's recommendation, based on his real-world tests and erected an unfolded vertical dipole ~12m up - excellent results from Winter Hill ~30km distant.

In article <a52013c9-6384-49c2-aa92-bf7a5d28a70an@googlegroups.com>,
R. Mark Clayton <notyalckram@gmail.com> wrote:

> Indeed the hiss was there on stereo FM, however it was is some way
> inversely proportional to the received signal strength. On a
> remote [weak] station the hiss was quite intrusive, whereas on a
> good signal barely discernable, usually in quieter passages.

> This made it worthwhile to erect a decent aerial. I took Bill
> Wright's recommendation, based on his real-world tests and erected
> an unfolded vertical dipole ~12m up - excellent results from Winter
> Hill ~30km distant.

A post I can agree with 100%.

Bob.

In article <a52013c9-6384-49c2-aa92-bf7a5d28a70an@googlegroups.com>, R.
Mark Clayton <notyalckram@gmail.com> wrote:
> On Friday, 23 June 2023 at 08:50:50 UTC+1, Roderick Stewart wrote:
> > On Thu, 22 Jun 2023 23:56:51 +0100, NY <m...@privacy.net> wrote:
> >
> SNIP
> > The hiss wasn't loud but it was there. At normal listening levels it
> > wasn't annoying, as it was simply what we'd all been used to since the
> > start of 625/50 broadcasting. But turn the volume up and switch
> > between NICAM and FM and it was clearly present, but only on FM. It
> > just sounded like a white noise generator being switched on and off
> > with everything else remaining the same.
> >
> > Rod.

> Indeed the hiss was there on stereo FM, however it was is some way
> inversely proportional to the received signal strength. On a remote
> [weak] station the hiss was quite intrusive, whereas on a good signal
> barely discernable, usually in quieter passages.

> This made it worthwhile to erect a decent aerial. I took Bill Wright's
> recommendation, based on his real-world tests and erected an unfolded
> vertical dipole ~12m up - excellent results from Winter Hill ~30km
> distant.

It can also depend on how far up the treble control is set. I once went to
see someone who complained bitterly about the hiss on R3. I adjusted the
controls so that the human voice sound normal - and the hiss went away!
But, the listener didn't like the result.

--
from KT24 in Surrey, England - sent from my RISC OS 4té
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

I can tell you it was82. I bought my first cds then then went around the
shops getting demos. Philips sounded a lot better than Sony. I have a CD100
still working. However all of the early had no real buffer memory so were
very prone to being disturbed.
We went through a golden arreain the late 90s, as they did much better at
recording bass and less tinkly treble and less prone to knocks. Sadly though
the studios that do popular music nowadays have so much compression on the
recording then Vinyl will probably sound the same.
The current fad seems to be to use both DVD and blue ray for surround sound
versions of the stereo releases and some very good remixes of older analogue
material are out there. However the way these are mostly consumed seems to
be on streaming services now. In other words, you never own a copy its just
dredged up on a server and played to you.
I have to say that a good stereo or surround live performance these days
does sound better than the CD made from the same source. Its less brash and
more balanced. The difference could be the 96khz sample rate might have
something to do with that.
Brian

--
Brian Gaff - briang1@blueyonder.co.uk

Blind user, so no pictures please!

This document should only be read by those persons for whom Paranoia is
normal
and its contents are probably boring and confusing. If you receive this
e-Mail
message in error, do not notify the sender immediately, instead, print it
out and make
paper animals out of it. As the rest of this disclaimer is totally
incomprehensible, we have not bothered to attach it.
"JNugent" <jnugent@mail.com> wrote in message
news:kfb35iFeltiU1@mid.individual.net...
> On 07/06/2023 10:12 pm, NY wrote:
>> "JNugent" <jenningsandco@mail.com> wrote in message
>> news:kebs2sFjr8fU1@mid.individual.net...
>>> On 01/06/2023 03:56 pm, NY wrote:
>>>>
>>>>
>>>> "R. Mark Clayton" <notyalckram@gmail.com> wrote in message
>>>> news:582911af-b735-4784-b6b5-cfd3a62f4064n@googlegroups.com...
>>>>> On Thursday, 1 June 2023 at 14:30:06 UTC+1, charles wrote:
>>>>>> In article <5aadb3...@sick-of-spam.invalid>,
>>>>>
>>>>> Snip
>>>>
>>>>>> Please remember that until 1979, all we had to listed to were LPs.
>>>>
>>>>> and then in 1985 along came something better...
>>>>
>>>> It was before 1985. I remember in my first year at university (so 1982)
>>>> going with some friends to hear a demo of a CD player at a hifi shop.
>>>
>>> ISTR compact disc being demonstrated on BBC "Tomorrow's World". It
>>> seemed like distant sci-fi. The uploader says he thinks it was 1981
>>> (though I think it was a bit later than that).
>>>
>>> <https://www.youtube.com/watch?v=bMp1pSVxoqw>
>>
>> I first heard a CD demonstrated for real (ie not on Tomorrow's World
>> where the weakest link is the TV sound transmission and reproduction) in
>> my first year at university, so autumn 1981 at the earliest.
>
> My earliest exposure (other than it being mentioned in print) was that
> edition of "Tomorrow's World". The presenter (can't remember who) said to
> camera that viewers ought to be able to hear the difference between vinyl
> and CD versions over the air. Whether I did or not is something I don't
> recall, but it is easy to kid yourself in these circumstances.
>>
>> The salesman chose various dramatic orchestral and rock tracks, and the
>> improved dynamic range was fantastic: so far they only time I'd head
>> anything approaching it was FM radio. But, canny lad that he was, he then
>> chose some very quiet music where the volume had to be turned up, and we
>> realised that the equivalent record would be marred by record noise
>> (dust, scratches, crud on the bottom of the groove).
>
> For me, the moment the penny finally dropped was when I bought a £3.99 CD
> in 1990 (because it contained one track I needed) and played back - on
> headphones - a track which started with a long, quiet intro on orchestral
> windchimes. I already that on vinyl, but for the first time, I was hearing
> it without surface noise and clicks.
>>
>> The final bit of the demo was about the durability of CDs. He took out a
>> demo CD and made a radial scratch with a sewing needle. He played it and
>> there was no noise at all. (OK, to demonstrate the error-correction, he
>> really should have made a circumferential scratch!) My mate, a great big
>> burly Mancunian who was built like a brick shithouse, said "Giz it here"
>> and he gouged a trench in the disc. The salesman went pale, but he played
>> the disk. There was a rhythmic ticking and occasional skipping. "*Now*
>> I'm *really* impressed," my mate said. "Do that to a record and you'd rip
>> the f-ing needle off".
>>
>> Things have come a long way since then. CD players can all now be
>> programmed to play a set of tracks, either in a fixed order or in random
>> order. You can skip to the beginning of any track without any of the
>> imprecision over cueing and the thump as the needle goes down. Some CD
>> players can even interrogate a central database and display the name of
>> the disc and the list of tracks. Quite why the CD standard didn't include
>> that information on the disc is a complete mystery to me - they missed a
>> trick there.
>
> The Sergeant Pepper CD can apparently be played back so that "Her Majesty"
> isn't chopped in two. I think it'd be more convincing if I ripped to *.wav
> and rearranged the section seamlessly on Audition.
>>
>> But we then have player software, either on dedicated hardware or on a
>> PC. And that can play from a computer disc (hard, USB, SSD etc) without a
>> removable physical medium being necessary. OK. it brings in the dreaded
>> subject of lossy compression on MP3, but as with anything in engineering,
>> there is a compromise between file size and sound quality. I find that I
>> cannot distinguish between 256 kbps MP3 file and (uncompressed) WAV file
>> from which it was generated. Only when you get down to 128 kbps can a
>> slight grittiness and bubbling-mud sound be heard - but you have to
>> listen hard at a normal playing volume.
>>
>> I have kept all my CDs as backups, even if for convenience I tend to play
>> the iTunes copy that I made from the CD. I also have an external USB HDD
>> with a copy of my music library, just in case.
>>
>> I do have a box of LPs as well - older music that predates CDs. The sound
>> quality is still very good - as long as you can mentally filter out the
>> background crap (dust-tick, scratch-click and constant roaring sound of
>> the crud in the grooves).
>
> That's the problem, isn't it?
>
>> Some records are a lot better than others. Choral/organ music (I was
>> digitising some old LPs belong to my parents-in-law) sounds DIRE:
>> horrendous distortion and obnoxious background crap. Most music seems to
>> be better, though the dynamic compression of pop music makes the
>> background crap much less noticeable than the very wide dynamic range and
>> quiet sections of classic music.
>>
>> I made WAV copies of some of the LPs for my dad, having cleaned the
>> records with a damp (or even dripping wet!) cloth to try to wash out the
>> crud from the grooves, and in a few cases I had to play tracks "wet"
>> (drip a puddle of water onto the track so it covers it fairly uniformly
>> and let the needle sit in the water on the grooves. There was a bit of
>> loss of high frequencies, but that was often preferable to background
>> noise. Maybe some of those old LPs are now available in CD form or even
>> on Youtube.
>
> Adobe Audition (or even predecessor app Cool Edit Pro, if your PC will run
> it still) has excellent vinyl restoration tools within it.
>

In article <u723nd$3clec$1@dont-email.me>, NY <me@privacy.invalid>
scribeth thus
>"R. Mark Clayton" <notyalckram@gmail.com> wrote in message
>news:6a9d7bcb-2ba4-42c5-99a9-a6f83d0b7299n@googlegroups.com...
>> Indeed, although reasonable [mono] with a decent receiver. Ni-cam was
>> quite close to FM played through an external system.
>
>NICAM sounded better than FM, close to CD. FM was good, but I never heard a
>stereo FM radio that didn't have at least *some* hiss - and the dreaded
>intrusive sibilance on female newsreaders' voices.
>

Ever tried a Yamaha CT-7000 on a good aerial?..

--
Tony Sayer

Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.

In article <jlArHHBhNLmkFwM1@bancom.co.uk>,
tony sayer <tony@bancom.co.uk> wrote:
> In article <u723nd$3clec$1@dont-email.me>, NY <me@privacy.invalid>
> scribeth thus
> >"R. Mark Clayton" <notyalckram@gmail.com> wrote in message
> >news:6a9d7bcb-2ba4-42c5-99a9-a6f83d0b7299n@googlegroups.com...
> >> Indeed, although reasonable [mono] with a decent receiver. Ni-cam was
> >> quite close to FM played through an external system.
> >
> >NICAM sounded better than FM, close to CD. FM was good, but I never heard a
> >stereo FM radio that didn't have at least *some* hiss - and the dreaded
> >intrusive sibilance on female newsreaders' voices.
> >

> Ever tried a Yamaha CT-7000 on a good aerial?..

Indeed. Sibilance is a product of multipath reception.

--
from KT24 in Surrey, England - sent from my RISC OS 4té
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

"charles" <charles@candehope.me.uk> wrote in message
news:5aba4066adcharles@candehope.me.uk...
> In article <jlArHHBhNLmkFwM1@bancom.co.uk>,
> tony sayer <tony@bancom.co.uk> wrote:
>> In article <u723nd$3clec$1@dont-email.me>, NY <me@privacy.invalid>
>> scribeth thus
>> >"R. Mark Clayton" <notyalckram@gmail.com> wrote in message
>> >news:6a9d7bcb-2ba4-42c5-99a9-a6f83d0b7299n@googlegroups.com...
>> >> Indeed, although reasonable [mono] with a decent receiver. Ni-cam was
>> >> quite close to FM played through an external system.
>> >
>> >NICAM sounded better than FM, close to CD. FM was good, but I never
>> >heard a
>> >stereo FM radio that didn't have at least *some* hiss - and the dreaded
>> >intrusive sibilance on female newsreaders' voices.
>> >
>
>> Ever tried a Yamaha CT-7000 on a good aerial?..
>
> Indeed. Sibilance is a product of multipath reception.

Is the reason that sibilance wasn't a problem with TV's FM soundtrack due to
the fact that TVs with built-in speakers had such poor HF audio response
that it wasn't very audible? Presumably if the pictures were free from
ghosting, sibilance wouldn't be a problem even with an audio connection to a
better amplifier and speakers, given that ghosting and sibilance are both
due to multipath.

I noticed sibilance with my Technics tuner, even when connected to an
external radio aerial. Mind you, that was a cable TV/radio feed provided to
all houses in Bracknell (to avoid each house having external aerials), with
a common feed and a TV/radio splitter, and the distribution amplifiers may
have introduced multipath if there were reflections in the cable. But I
don't remember ghosted TV pictures. Maybe if there was any multipath, it
affected VHF radio more than UHF TV.

At my next house near Didcot, so receiving from Oxford, I admit that I
plugged my TV aerial, via a normal TV splitter, into the radio tuner's
aerial socket. Not ideal, but hopefully even a UHF-optimised aerial gave a
good enough signal strength and a flat enough response for VHF FM not to
"notice".

On Sun, 25 Jun 2023 23:59:26 +0100, "NY" <me@privacy.invalid> wrote:

>I noticed sibilance with my Technics tuner, even when connected to an
>external radio aerial. Mind you, that was a cable TV/radio feed provided to
>all houses in Bracknell (to avoid each house having external aerials), with
>a common feed and a TV/radio splitter, and the distribution amplifiers may
>have introduced multipath if there were reflections in the cable. But I
>don't remember ghosted TV pictures. Maybe if there was any multipath, it
>affected VHF radio more than UHF TV.

Reflections in a 100 metre cable will produce multipath echoes at
intervals of one microsecond. An echo of that duration can be clearly
seen on a TV picture (which is only 52 microseconds wide), but I
wouldn't have thought it would be likely to produce audible effects.

Rod.

On Monday, 26 June 2023 at 06:09:02 UTC+1, Roderick Stewart wrote:
> On Sun, 25 Jun 2023 23:59:26 +0100, "NY" <m...@privacy.invalid> wrote:
>
> >I noticed sibilance with my Technics tuner, even when connected to an
> >external radio aerial. Mind you, that was a cable TV/radio feed provided to
> >all houses in Bracknell (to avoid each house having external aerials), with
> >a common feed and a TV/radio splitter, and the distribution amplifiers may
> >have introduced multipath if there were reflections in the cable. But I
> >don't remember ghosted TV pictures. Maybe if there was any multipath, it
> >affected VHF radio more than UHF TV.
> Reflections in a 100 metre cable will produce multipath echoes at
> intervals of one microsecond. An echo of that duration can be clearly
> seen on a TV picture (which is only 52 microseconds wide), but I
> wouldn't have thought it would be likely to produce audible effects.
>
> Rod.
100m cable transit ~= 0.5mS

On Monday, 26 June 2023 at 11:44:13 UTC+1, R. Mark Clayton wrote:
> On Monday, 26 June 2023 at 06:09:02 UTC+1, Roderick Stewart wrote:
> > On Sun, 25 Jun 2023 23:59:26 +0100, "NY" <m...@privacy.invalid> wrote:
> >
> > >I noticed sibilance with my Technics tuner, even when connected to an
> > >external radio aerial. Mind you, that was a cable TV/radio feed provided to
> > >all houses in Bracknell (to avoid each house having external aerials), with
> > >a common feed and a TV/radio splitter, and the distribution amplifiers may
> > >have introduced multipath if there were reflections in the cable. But I
> > >don't remember ghosted TV pictures. Maybe if there was any multipath, it
> > >affected VHF radio more than UHF TV.
> > Reflections in a 100 metre cable will produce multipath echoes at
> > intervals of one microsecond. An echo of that duration can be clearly
> > seen on a TV picture (which is only 52 microseconds wide), but I
> > wouldn't have thought it would be likely to produce audible effects.
> >
> > Rod.
> 100m cable transit ~= 0.5mS

Wrong symbol 0.5 micro-seconds, you won't hear 2MHz

On 26/06/2023 11:44, R. Mark Clayton wrote:
> On Monday, 26 June 2023 at 06:09:02 UTC+1, Roderick Stewart wrote:
>> On Sun, 25 Jun 2023 23:59:26 +0100, "NY" <m...@privacy.invalid> wrote:
>>
>>> I noticed sibilance with my Technics tuner, even when connected to an
>>> external radio aerial. Mind you, that was a cable TV/radio feed provided to
>>> all houses in Bracknell (to avoid each house having external aerials), with
>>> a common feed and a TV/radio splitter, and the distribution amplifiers may
>>> have introduced multipath if there were reflections in the cable. But I
>>> don't remember ghosted TV pictures. Maybe if there was any multipath, it
>>> affected VHF radio more than UHF TV.
>> Reflections in a 100 metre cable will produce multipath echoes at
>> intervals of one microsecond. An echo of that duration can be clearly
>> seen on a TV picture (which is only 52 microseconds wide), but I
>> wouldn't have thought it would be likely to produce audible effects.
>>
>> Rod.
> 100m cable transit ~= 0.5mS

ICBW but thought Rod meant 100m of cable so the reflected signal (going
there, back, and there again) had to travel an extra 200m

--
Robin
reply-to address is (intended to be) valid

On 26/06/2023 11:58, Robin wrote:
> On 26/06/2023 11:44, R. Mark Clayton wrote:
>> On Monday, 26 June 2023 at 06:09:02 UTC+1, Roderick Stewart wrote:
>>> On Sun, 25 Jun 2023 23:59:26 +0100, "NY" <m...@privacy.invalid> wrote:
>>>
>>>> I noticed sibilance with my Technics tuner, even when connected to an
>>>> external radio aerial. Mind you, that was a cable TV/radio feed
>>>> provided to
>>>> all houses in Bracknell (to avoid each house having external
>>>> aerials), with
>>>> a common feed and a TV/radio splitter, and the distribution
>>>> amplifiers may
>>>> have introduced multipath if there were reflections in the cable. But I
>>>> don't remember ghosted TV pictures. Maybe if there was any
>>>> multipath, it
>>>> affected VHF radio more than UHF TV.
>>> Reflections in a 100 metre cable will produce multipath echoes at
>>> intervals of one microsecond. An echo of that duration can be clearly
>>> seen on a TV picture (which is only 52 microseconds wide), but I
>>> wouldn't have thought it would be likely to produce audible effects.
>>>
>>> Rod.
>>   100m cable transit ~= 0.5mS
>
> ICBW but thought Rod meant 100m of cable so the reflected signal (going
> there, back, and there again) had to travel an extra 200m

If "Reflections in a 100 metre cable will produce multipath echoes at
intervals of one microsecond", then you need to have a 500 of those
there-and-back reflections to make up a total time of 0.5 msec or 500 usec.

Is a speed of 10^8 m/sec (roughly 1/3 of the speed of light) about right
for the speed of a signal in a coax cable? That's what 100 m in 1 usec
corresponds to.

On 26/06/2023 16:46, NY wrote:
> On 26/06/2023 11:58, Robin wrote:
>> On 26/06/2023 11:44, R. Mark Clayton wrote:
>>> On Monday, 26 June 2023 at 06:09:02 UTC+1, Roderick Stewart wrote:
>>>> On Sun, 25 Jun 2023 23:59:26 +0100, "NY" <m...@privacy.invalid> wrote:
>>>>
>>>>> I noticed sibilance with my Technics tuner, even when connected to an
>>>>> external radio aerial. Mind you, that was a cable TV/radio feed
>>>>> provided to
>>>>> all houses in Bracknell (to avoid each house having external
>>>>> aerials), with
>>>>> a common feed and a TV/radio splitter, and the distribution
>>>>> amplifiers may
>>>>> have introduced multipath if there were reflections in the cable.
>>>>> But I
>>>>> don't remember ghosted TV pictures. Maybe if there was any
>>>>> multipath, it
>>>>> affected VHF radio more than UHF TV.
>>>> Reflections in a 100 metre cable will produce multipath echoes at
>>>> intervals of one microsecond. An echo of that duration can be clearly
>>>> seen on a TV picture (which is only 52 microseconds wide), but I
>>>> wouldn't have thought it would be likely to produce audible effects.
>>>>
>>>> Rod.
>>>   100m cable transit ~= 0.5mS
>>
>> ICBW but thought Rod meant 100m of cable so the reflected signal
>> (going there, back, and there again) had to travel an extra 200m
>
> If "Reflections in a 100 metre cable will produce multipath echoes at
> intervals of one microsecond", then you need to have a 500 of those
> there-and-back reflections to make up a total time of 0.5 msec or 500 usec.

I was addressing only the factor 2 difference in the mantissa. The
minor matter of a difference of 3 in the decimal exponent had already
been dealt with.

> Is a speed of 10^8 m/sec (roughly 1/3 of the speed of light) about right
> for the speed of a signal in a coax cable? That's what 100 m in 1 usec
> corresponds to.

My recollection was /about/ two-thirds of vacuum.

--
Robin
reply-to address is (intended to be) valid

On Mon, 26 Jun 2023 16:46:24 +0100, NY <me@privacy.net> wrote:

>Is a speed of 10^8 m/sec (roughly 1/3 of the speed of light) about right
>for the speed of a signal in a coax cable? That's what 100 m in 1 usec
>corresponds to.

For 75 Ohm video cable it's almost exactly 2/3, or in other words, 200
metres per microsecond. The reflection from the open or shorted far
end of 100 metre cable appears 1 microsecond after the original signal
at the near end. (The reflected signal has had to travel twice the
length of the cable).

You can clearly see this on a scope, or a picture monitor, but I can't
imagine how this sort of delay would produce any observable effect on
an audio signal.

Rod.

In article <6884f2e0-c214-f00e-4136-1c0999207b8a@outlook.com>, Robin
<rbw@outlook.com> wrote:
> On 26/06/2023 16:46, NY wrote:
> > On 26/06/2023 11:58, Robin wrote:
> >> On 26/06/2023 11:44, R. Mark Clayton wrote:
> >>> On Monday, 26 June 2023 at 06:09:02 UTC+1, Roderick Stewart wrote:
> >>>> On Sun, 25 Jun 2023 23:59:26 +0100, "NY" <m...@privacy.invalid>
> >>>> wrote:
> >>>>
> >>>>> I noticed sibilance with my Technics tuner, even when connected to
> >>>>> an external radio aerial. Mind you, that was a cable TV/radio feed
> >>>>> provided to all houses in Bracknell (to avoid each house having
> >>>>> external aerials), with a common feed and a TV/radio splitter, and
> >>>>> the distribution amplifiers may have introduced multipath if there
> >>>>> were reflections in the cable. But I don't remember ghosted TV
> >>>>> pictures. Maybe if there was any multipath, it affected VHF radio
> >>>>> more than UHF TV.
> >>>> Reflections in a 100 metre cable will produce multipath echoes at
> >>>> intervals of one microsecond. An echo of that duration can be
> >>>> clearly seen on a TV picture (which is only 52 microseconds wide),
> >>>> but I wouldn't have thought it would be likely to produce audible
> >>>> effects.
> >>>>
> >>>> Rod.
> >>> 100m cable transit ~= 0.5mS
> >>
> >> ICBW but thought Rod meant 100m of cable so the reflected signal
> >> (going there, back, and there again) had to travel an extra 200m
> >
> > If "Reflections in a 100 metre cable will produce multipath echoes at
> > intervals of one microsecond", then you need to have a 500 of those
> > there-and-back reflections to make up a total time of 0.5 msec or 500
> > usec.

> I was addressing only the factor 2 difference in the mantissa. The
> minor matter of a difference of 3 in the decimal exponent had already
> been dealt with.

> > Is a speed of 10^8 m/sec (roughly 1/3 of the speed of light) about
> > right for the speed of a signal in a coax cable? That's what 100 m in
> > 1 usec corresponds to.

> My recollection was /about/ two-thirds of vacuum.

I thought, from many years ago, that the velocity factor in co-ax was about
80%

> -

--
from KT24 in Surrey, England - sent from my RISC OS 4té
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

In article <5abaafbc38charles@candehope.me.uk>, charles
<charles@candehope.me.uk> scribeth thus
>In article <6884f2e0-c214-f00e-4136-1c0999207b8a@outlook.com>, Robin
><rbw@outlook.com> wrote:
>> On 26/06/2023 16:46, NY wrote:
>> > On 26/06/2023 11:58, Robin wrote:
>> >> On 26/06/2023 11:44, R. Mark Clayton wrote:
>> >>> On Monday, 26 June 2023 at 06:09:02 UTC+1, Roderick Stewart wrote:
>> >>>> On Sun, 25 Jun 2023 23:59:26 +0100, "NY" <m...@privacy.invalid>
>> >>>> wrote:
>> >>>>
>> >>>>> I noticed sibilance with my Technics tuner, even when connected to
>> >>>>> an external radio aerial. Mind you, that was a cable TV/radio feed
>> >>>>> provided to all houses in Bracknell (to avoid each house having
>> >>>>> external aerials), with a common feed and a TV/radio splitter, and
>> >>>>> the distribution amplifiers may have introduced multipath if there
>> >>>>> were reflections in the cable. But I don't remember ghosted TV
>> >>>>> pictures. Maybe if there was any multipath, it affected VHF radio
>> >>>>> more than UHF TV.
>> >>>> Reflections in a 100 metre cable will produce multipath echoes at
>> >>>> intervals of one microsecond. An echo of that duration can be
>> >>>> clearly seen on a TV picture (which is only 52 microseconds wide),
>> >>>> but I wouldn't have thought it would be likely to produce audible
>> >>>> effects.
>> >>>>
>> >>>> Rod.
>> >>> 100m cable transit ~= 0.5mS
>> >>
>> >> ICBW but thought Rod meant 100m of cable so the reflected signal
>> >> (going there, back, and there again) had to travel an extra 200m
>> >
>> > If "Reflections in a 100 metre cable will produce multipath echoes at
>> > intervals of one microsecond", then you need to have a 500 of those
>> > there-and-back reflections to make up a total time of 0.5 msec or 500
>> > usec.
>
>> I was addressing only the factor 2 difference in the mantissa. The
>> minor matter of a difference of 3 in the decimal exponent had already
>> been dealt with.
>
>> > Is a speed of 10^8 m/sec (roughly 1/3 of the speed of light) about
>> > right for the speed of a signal in a coax cable? That's what 100 m in
>> > 1 usec corresponds to.
>
>> My recollection was /about/ two-thirds of vacuum.
>
>I thought, from many years ago, that the velocity factor in co-ax was about
>80%
>
>> -
>
Yes around that, some even lower!...

--
Tony Sayer

Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.