In article ,
Don Pearce wrote:
The big step reduction in quality happened when digital broadcasting
began.

Not quite. The first HD broadcasts via OnDdigital were considerably better
than today.

--
*I stayed up all night to see where the sun went. Then it dawned on me.*

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

Vir Campestris wrote:
Phil Allison wrote:



Your device will work perfectly when you are comparing two amps.


** Yes, and the result shows how useless all A then B tests are and by implication variations like ABX.

Soon as you pause and repeat a passage of music, imaginary differences appear.

People who auditioned my test set up were first given and A then B test using a music track known to them, in a quiet, well damped room and listening via Quad ESL57 speakers. The track could be from an LP or a CD.

All heard clear differences in this test - even me.

Then they were handed the switchover button and could swap amplifiers any time they liked while listening to the same track.

All reacted the exact same way, with a puzzled look and told me the button was not working. So I turned off the AC power to one amp and showed them it was.

The smarter ones got it, realising that the previously heard differences were the result of imperfect memory. The less smart ones were dumbfounded.

I loaned the set-up and spare amp to one audiophile in the above category to use at home for a week - at the end of which he agreed the amps sounded the same, a reversal of all his previous opinions.


I daresay a variant of it would work well with two speakers.

** Speakers DO sound different, as one would expect, since they do not test the same. Having an instant changeover makes comparison tests very easy though and eliminates imaginary differences.



The difference with digital encoding is that there may be a difference
that is not perceptible. If the phase of the bass is inverted nobody
will notice - probably not even if its harmonics aren't. But your box
would cause a click when switching such a pair of signals.


** Yes, a phase reversal would cause an audible click when doing the set up procedure - especially if a sine tone were used.


When I merge two digital signals I try to do it on a zero crossing
point. Your box won't.


** When crossing from one signal to an identical one, using a changeover relay, the interruption is under 1mS and as I found non-audible on programme.

The relay itself could just be heard, when the room was dead silent.


.... Phil

On Mon, 23 Jan 2017 01:02:05 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Don Pearce wrote:
The big step reduction in quality happened when digital broadcasting
began.

Not quite. The first HD broadcasts via OnDdigital were considerably better
than today.

Yes, that's true. But it wasn't ten minutes before the accountants
learned that you could cram more channels in by cutting bit rates.

d

In article , Bill Taylor
wrote:

Yes, it would be nice if DAB had higher data rates and it would be nice
if R3 FM wasn't DRC'd to death, but they aren't the only source of
audio. There are huge quantities of well recorded, well performed music
available for very little money.

It seems a little excessive to say R3 FM is "RDC'd to death" given how much
better it is in this respect than the norm for other channels.

Jim

--
Please use the address on the audiomisc page 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

In article , Dave Plowman (News)
wrote:
In article , Johan Helsingius
wrote:
On 22-01-17 19:24, Don Pearce wrote:

So yes. Everything is deteriorating. This is happening because
unlike FM, digital broadcasting makes it too easy to do.

Hasn't BBC FM broadcasts been transmitted using a digital backbone
since the early 80's or so?

Yes. But since it goes via landlines, no need to reduce the bandwidth to
save costs.

Actually, I'm not sure that even the BBC now know the routes and methods
used as they are 'outsourced'. I assume that all they know or expect is
that they shove NICAM in one end and it comes out the other at the TXs.
Beyond that, I guess it is in the "ain't broke, don't fix it" category.

Jim

--
Please use the address on the audiomisc page 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

In article , Phil
Allison wrote:

I daresay a variant of it would work well with two speakers.

** Speakers DO sound different, as one would expect, since they do not
test the same. Having an instant changeover makes comparison tests very
easy though and eliminates imaginary differences.

A potential problem here would be that speakers, in general, don't stop
radiating the instant you abruptly cut off input to them. So when you
switched, one would still be 'ringing down' in its own way as the other
speaker 'gets going'. Hence getting an 'inaudible' changeover in itself may
require both speakers to be pretty good. And in addition, the two speakers
can't be in the same place, and that may affect things. So - as ever -
trying to assess and design speakers may remain a challenge.

Jim

--
Please use the address on the audiomisc page 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

On 23/01/2017 08:26, Don Pearce wrote:
On Mon, 23 Jan 2017 01:02:05 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Don Pearce wrote:
The big step reduction in quality happened when digital broadcasting
began.

Not quite. The first HD broadcasts via OnDdigital were considerably better
than today.

Yes, that's true. But it wasn't ten minutes before the accountants
learned that you could cram more channels in by cutting bit rates.


ITV fell foul of that in their first attempt at going digital.
Initially aimed at selling sport to pubs with the promise of lots of
choice but the pictures were very prone to break-up and it was an
expensive flop.

--
Graeme Wall
This account not read.

In article ,
Don Pearce wrote:
On Mon, 23 Jan 2017 01:02:05 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Don Pearce wrote:
The big step reduction in quality happened when digital broadcasting
began.

Not quite. The first HD broadcasts via OnDdigital were considerably
better than today.

Yes, that's true. But it wasn't ten minutes before the accountants
learned that you could cram more channels in by cutting bit rates.

It's what the public want. Apparently.

--
*Is there another word for synonym?

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

In article ,
Graeme Wall wrote:
Not quite. The first HD broadcasts via OnDdigital were considerably
better than today.

Yes, that's true. But it wasn't ten minutes before the accountants
learned that you could cram more channels in by cutting bit rates.


ITV fell foul of that in their first attempt at going digital.
Initially aimed at selling sport to pubs with the promise of lots of
choice but the pictures were very prone to break-up and it was an
expensive flop.

Not quite sure what you mean. The OnDigital system effectively morphed
into FreeView.

I had OnDigital from the start, and didn't have problems with picture
break up. But like all digital systems it reacts differently to a poor
signal than analogue.

--
*Support bacteria - they're the only culture some people have *

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

On 23/01/2017 11:12, Dave Plowman (News) wrote:
In article ,
Graeme Wall wrote:
Not quite. The first HD broadcasts via OnDdigital were considerably
better than today.

Yes, that's true. But it wasn't ten minutes before the accountants
learned that you could cram more channels in by cutting bit rates.


ITV fell foul of that in their first attempt at going digital.
Initially aimed at selling sport to pubs with the promise of lots of
choice but the pictures were very prone to break-up and it was an
expensive flop.

Not quite sure what you mean. The OnDigital system effectively morphed
into FreeView.

When the BBC got involved.


I had OnDigital from the start, and didn't have problems with picture
break up. But like all digital systems it reacts differently to a poor
signal than analogue.


AIUI the initial OnDigital service was not marketed to home subscribers,
but I could be wrong!

--
Graeme Wall
This account not read.