My threshold for detecting artefacts in audio is around 128 kbps for MP3: I
can distinguish that from anything higher, but I can't hear any difference
between (for example) 192 and 320 kbps.

The difference between analogue (especially vinyl) and digital (CD) is VERY
noticeable: vinyl suffers very badly from disc noise, even on a brand new
record from an expensive record label (ie not made on the cheap), whereas CD
sounds perfect. And dust and scratches are very hard to avoid.

Many years ago I was invited to a few audio tests involving amplifiers
and speakers at the home of a Dr Derek Scotland the designer of the old
Audiolab range before they sold out.

He had a pair of Quad ELS 63 electrostatic speakers these driven by his
200 watt Monoblock amps.

He was playing some excellent music and I didn't at first notice where
the source was as that was in the room next door it all being so that
you couldn't see what amps were actually being used etc..

I was staggered to find that what I'd been listening to was off Vinyl
disc!!

He did say that he didn't expect me to have heard it like that before as
the discs were pressed by a specialist company in Japan or Germany and
used much higher grade Vinyl than anyone would normally use.

Course it didn't get round the end of side distortion and other
artefacts that disc can and does introduce but I was really taken as to
how good it could be !...


As an aside, I've always wondered about people who say they prefer vinyl to
CD. Do they prefer the imperfections and signal processing that vinyl
introduces, I wonder? Do they find a live performance (mic, amplifier,
speakers) as bad as a CD, or do they find that the digitisation modifies the
signal - can they distinguish live electronic (all analogue) from CD?

Ask that of such as the shellac collective when you see them playing at
places like bestival...

http://www.youtube.com/watch?v=eaCDkaNSe1g

I once suggested that it would be simpler to put all their stuff on USB
sticks..

Dare you to suggest that to them, almost got lynched to shouts of
blasphemer!! and heretic!!;!...



Yeah but you are so young you've probably never seen or heard what
good systems fed with good signals are like or haven't had the
artifacts of the systems failings pointed out.

The population as a whole seem to think that Freeview DTTV is fine. I
find it almost unwatchable with all the artifacts the from lossy
compression that is applied to bring the 1 *Giga* bps plus out of the
back of a camera to around 2 *Mega* bps on Freeview. DSAT is better
but still has some problems but no where near as distracting. Both
DTV and DSAT, even in HD, are kicked into a cocked hat by Blu-Ray on
a decent "Full-HD" screen.

I hadn't realised that the output from a camera is as high as 1 Gbps. That
really is a LOT of compression to get it down to 1-2 Mbps.

I mainly watch TV (DTV) on my PC screen, sometimes in a window that only
occupies part of the screen, but then I am only a foot or so from the
screen. Mostly I'm not aware of compression artefacts of DTTV but there are
occasions on a very detailed picture when the camera pans and all detail is
lost or replaced with large blocks for a moment. But then I've seen some
DVDs where that happens.

Having said that, I am very conscious of the PAL artefacts (coloured fringes
around vertical edges, especially captions, and a fine dot pattern) on any
old programmes (eg repeats of 1970s or 80s programmes, or old news footage).

Thats depended on how well that was recorded and whether or not there
was a good comb filter in the receiver. I have seen studio originated
PAL pix and they were excellent...


HD on DSat is a great disappointment. I remember watching the Opening and
Closing Ceremonies of the Olympics just after we got Sky and being very
aware of the compression artefacts.

The biggest problem with digital TV is that it doesn't handle overexposure
very gracefully. Drama is usually well graded and the picture is perfect,
but a lot of documentaries, especially fly-on-the-wall types, suffer from
horrendous featureless orange skin tones or other bleached colour.

Prolly done on cheaper hand held cameras by less than experienced
persons..

Tube
cameras had their faults (lag, smear) but somehow they managed to make
overexposure less objectionable.


We've got a SONY Bravia and I'm quite picky of faults but by and large
it makes a very good job of processing the signals but can't put right
such as the bad audio in programmes like Jamaica Inn recently;!..


There does seem still quite a variation on the actual pix produced by
DTV televisions..


Never forgot what my old English teacher once said never be put off bu
the cover and binding of a book, content is the key thing...
--
Tony Sayer