"Oliver Keating" wrote in
message ...
I was flicking through "What HiFi" magazine and I came across
something very
odd - a series of reviews on *digital* audio cables, for connecting
a CD
player to an amp.

There are comments such as "this cable brings across a crisp sound a
cut
above the rest"

Now, at this point I have to shake my head in disbelief. Surely a
digital
cable about 1 metre long can easily carry a 1mbit data stream with
no
errors. Bear in mind ethernet has to carry 100mbits.


Yes a "DIGITAL cable most certainly can, but a lot of so called
"digital" interconnects arn't made with DIGTAL grade cables, and the
plugs also are not true 75 ohm, so you will start to get line
reflections, ringing on the recieved pulses (and if they are of
sufecent signal level cause pulse signal coruption and drop-outs) this
could start adding to the error rate, resulting in a less "good a
sound".

about optical cables. There is absolutely
*no* way an optical pulse can be distorted sufficiently over 1 metre
that it
could result in an error.

This should be true ! BUT. Unfortunatly due to the design spec this
is not true.
There was some deep discussion on this whole issue a while back on
RAHE,
I too had thought like you. Then The Man from Belden explaind it
rather well: you could do a google on it his expanation should be a
lot better than mine.
But basically the Fibre call for in the spec is many times larger in
diameter that the wavelenght of the light used so instead on the light
bouncing down the fibre in a controlled fashon it bounces about in a
lot more random fashon and after a metre or three the uncontrolled
light bounces interfere with the main light signal generating extra
noise. This can cause misreading of the recieved signals, hence
errors, noise, distortion.
So by using a better fibre (which is not as cheap) that has a smaller
diameter, will improve the quality (by reducing the noise) at the
recieving end, resulting in less errors etc.

I can only think that the testers suffered some sort of placebo
effect, or
they are in cahoots with the industry in order to provide a supply
of
customers who will shell out £350 for the "best" optical cable.

No, what they heard in the test is valid.
Sorry, its just good engineering to fix, bad engineering in the first
place.
As to the question is a cable worth £350 ? Well only your ears, brain
and wallet can make that value judgment.
I personaly would look for a much less expensive option (good dacs are
less than that).

snip

Who ever said life was easy :¬)

Happy New Year
Chris

bit reduced

I just wonder if this magazine is just designed so that the industry is able
to flog expensive kit.


I think your scepticism has answered your own questions.....
--
Tony Sayer

bit reduced

I just wonder if this magazine is just designed so that the industry is able
to flog expensive kit.


I think your scepticism has answered your own questions.....
--
Tony Sayer

In article , Oliver Keating
wrote:
I was flicking through "What HiFi" magazine and I came across something
very odd - a series of reviews on *digital* audio cables, for connecting
a CD player to an amp.

There are comments such as "this cable brings across a crisp sound a cut
above the rest"
[snip]

I would treat such comments in magazines is a being 'somewhat unreliable'.
:-)

Which brings me onto CD players. I always thought that amplifier and
speakers mattered the most, but What HiFi reckons CD players are
important, and worthing spending loads of money on. Now, if you have a
CD player in a half decent Hi-Fi setup then you use a digital
interconnect, so really, all the CD player is having to do is read the
raw data off the CD and feed it to the Amp, and the cleverness of its
own DAC is neither here nor there.

The above apparently assumes you have a DAC inside the amp, and that this
is better than the one in the CD player. I doubt that either assumption is
correct in most cases for stereo audio systems. The situation with the
multichannel amps/receivers for AV may be different, though. These may have
digital inputs to allow the unit to process the digital stream from
something like a DVD player. However these aren't (currently at least) the
norm for serious stereo audio use.

So in a £1,000 CD player are you paying for a great DAC (which you won't
use) or simply some very good error correction in the reading process?

There are some differences between DACs due to the varied ways that they
sometimes deal with the digital stream and convert it to analogue. However
these differences may be modest/small in many cases in my experience once
you get above quite cheap players.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

On Sat, 03 Jan 2004 10:06:58 +0000, Jim Lesurf wrote:

In article , Oliver Keating
wrote:

[snip]

Which brings me onto CD players. I always thought that amplifier and
speakers mattered the most, but What HiFi reckons CD players are
important, and worthing spending loads of money on. Now, if you have a
CD player in a half decent Hi-Fi setup then you use a digital
interconnect, so really, all the CD player is having to do is read the
raw data off the CD and feed it to the Amp, and the cleverness of its
own DAC is neither here nor there.

The above apparently assumes you have a DAC inside the amp, and that
this is better than the one in the CD player. I doubt that either
assumption is correct in most cases for stereo audio systems. The
situation with the multichannel amps/receivers for AV may be different,
though. These may have digital inputs to allow the unit to process the
digital stream from something like a DVD player. However these aren't
(currently at least) the norm for serious stereo audio use.

This raises an interesting point; a while ago, I was planning on building
a modest home cinema/hi-fi rig and my plan was to treat it much the same
as I treat building computers; good quality central components
(motherboard, PSU, DAC/Amplifier) and Human IO devices (monitor, keyboard,
mouse, speakers) and spend what I can afford on the rest (CPU, memory,
video card, CD transports). The logic behind that is that I
don't want to spend large amounts of money on components that rapidly
become obsolete, but instead spend it on components that will be the last
to be upgraded and for which good quality/stability is necessary.

When I explained this to the guy behind the counter in Richer Sounds he
seemed a bit surprised but intrigued by my strategy. What does the
collective wisdom of u.r.a think?

[snip]

Jim

Best Regards,
Alex.
--
Alex Butcher Brainbench MVP for Internet Security: www.brainbench.com
Bristol, UK Need reliable and secure network systems?
PGP/GnuPG ID:0x271fd950 http://www.assursys.com/

Alex Butcher wrote:

This raises an interesting point; a while ago, I was planning on
building a modest home cinema/hi-fi rig and my plan was to treat it
much the same as I treat building computers; good quality central
components (motherboard, PSU, DAC/Amplifier) and Human IO devices
(monitor, keyboard, mouse, speakers) and spend what I can afford on
the rest (CPU, memory, video card, CD transports). The logic behind
that is that I
don't want to spend large amounts of money on components that rapidly
become obsolete, but instead spend it on components that will be the
last to be upgraded and for which good quality/stability is necessary.

I can see the thinking regarding computers - two components that can be
bought for a reasonable price/performance trade-off are CPU and hard disk.
But what parts of an audio system quickly become obsolete, such that the
same thinking can be applied?


--
Wally
www.art-gallery.myby.co.uk
On webcam: Black Cat In Coal Cellar

On Sat, 03 Jan 2004 17:38:06 +0000, Wally wrote:

Alex Butcher wrote:

This raises an interesting point; a while ago, I was planning on
building a modest home cinema/hi-fi rig and my plan was to treat it
much the same as I treat building computers; good quality central
components (motherboard, PSU, DAC/Amplifier) and Human IO devices
(monitor, keyboard, mouse, speakers) and spend what I can afford on the
rest (CPU, memory, video card, CD transports). The logic behind that is
that I
don't want to spend large amounts of money on components that rapidly
become obsolete, but instead spend it on components that will be the
last to be upgraded and for which good quality/stability is necessary.

I can see the thinking regarding computers - two components that can be
bought for a reasonable price/performance trade-off are CPU and hard
disk. But what parts of an audio system quickly become obsolete, such
that the same thinking can be applied?

Digital components such as CD/DVD players for a start, it would seem.
Analogue components admittedly (much) less so. But even then, these are
probably components you'd more readily want to upgrade in favour of better
components.

An example of the sort of systems I'm proposing would be:

~130GBP CD player
~100GBP DVD player
~150GBP HT receiver

vs.

~ 50GBP DVD player
~320GBP HT receiver
10GBP digital cable

Same overall price, but I would expect that the DAC in that ~320GBP
receiver is better than either of the DACS in the ~100GBP-range CD/DVD
players, and further, that the amplifier in the ~320GBP device is better
than the ~150GBP device. I wonder whether anyone could tell which was the
cheaper CD/DVD transport...

Of course, taking my approach literally, you'd want to get a HT decoder
and seperate amplifiers, so that the decoder (rapidly changing) can be
upgraded without having to ditch the (probably perfectly good) amplifiers.
Sadly, doing that would be rather expensive compared with an all-in-one.


Best Regards,
Alex.
--
Alex Butcher Brainbench MVP for Internet Security: www.brainbench.com
Bristol, UK Need reliable and secure network systems?
PGP/GnuPG ID:0x271fd950 http://www.assursys.com/

Alex Butcher wrote:

I can see the thinking regarding computers - two components that can
be bought for a reasonable price/performance trade-off are CPU and
hard disk. But what parts of an audio system quickly become
obsolete, such that the same thinking can be applied?

Digital components such as CD/DVD players for a start, it would seem.

Obsolete?


An example of the sort of systems I'm proposing would be:

~130GBP CD player
~100GBP DVD player
~150GBP HT receiver

Why both CD and DVD players?


~ 50GBP DVD player
~320GBP HT receiver
10GBP digital cable

Same overall price, but I would expect that the DAC in that ~320GBP
receiver is better than either of the DACS in the ~100GBP-range CD/DVD
players, and further, that the amplifier in the ~320GBP device is
better than the ~150GBP device.

I'm tempted to agree. What would be the upgrade candidate in the latter
system?


I wonder whether anyone could tell
which was the cheaper CD/DVD transport...

If they're all going through the DAC in the dearer HT amp, I think it would
be hard to tell.


--
Wally
www.art-gallery.myby.co.uk
On webcam: Black Cat In Coal Cellar

Alex Butcher wrote:

I can see the thinking regarding computers - two components that can
be bought for a reasonable price/performance trade-off are CPU and
hard disk. But what parts of an audio system quickly become
obsolete, such that the same thinking can be applied?

Digital components such as CD/DVD players for a start, it would seem.

Obsolete?


An example of the sort of systems I'm proposing would be:

~130GBP CD player
~100GBP DVD player
~150GBP HT receiver

Why both CD and DVD players?


~ 50GBP DVD player
~320GBP HT receiver
10GBP digital cable

Same overall price, but I would expect that the DAC in that ~320GBP
receiver is better than either of the DACS in the ~100GBP-range CD/DVD
players, and further, that the amplifier in the ~320GBP device is
better than the ~150GBP device.

I'm tempted to agree. What would be the upgrade candidate in the latter
system?


I wonder whether anyone could tell
which was the cheaper CD/DVD transport...

If they're all going through the DAC in the dearer HT amp, I think it would
be hard to tell.


--
Wally
www.art-gallery.myby.co.uk
On webcam: Black Cat In Coal Cellar

On Sat, 03 Jan 2004 17:38:06 +0000, Wally wrote:

Alex Butcher wrote:

This raises an interesting point; a while ago, I was planning on
building a modest home cinema/hi-fi rig and my plan was to treat it
much the same as I treat building computers; good quality central
components (motherboard, PSU, DAC/Amplifier) and Human IO devices
(monitor, keyboard, mouse, speakers) and spend what I can afford on the
rest (CPU, memory, video card, CD transports). The logic behind that is
that I
don't want to spend large amounts of money on components that rapidly
become obsolete, but instead spend it on components that will be the
last to be upgraded and for which good quality/stability is necessary.

I can see the thinking regarding computers - two components that can be
bought for a reasonable price/performance trade-off are CPU and hard
disk. But what parts of an audio system quickly become obsolete, such
that the same thinking can be applied?

Digital components such as CD/DVD players for a start, it would seem.
Analogue components admittedly (much) less so. But even then, these are
probably components you'd more readily want to upgrade in favour of better
components.

An example of the sort of systems I'm proposing would be:

~130GBP CD player
~100GBP DVD player
~150GBP HT receiver

vs.

~ 50GBP DVD player
~320GBP HT receiver
10GBP digital cable

Same overall price, but I would expect that the DAC in that ~320GBP
receiver is better than either of the DACS in the ~100GBP-range CD/DVD
players, and further, that the amplifier in the ~320GBP device is better
than the ~150GBP device. I wonder whether anyone could tell which was the
cheaper CD/DVD transport...

Of course, taking my approach literally, you'd want to get a HT decoder
and seperate amplifiers, so that the decoder (rapidly changing) can be
upgraded without having to ditch the (probably perfectly good) amplifiers.
Sadly, doing that would be rather expensive compared with an all-in-one.


Best Regards,
Alex.
--
Alex Butcher Brainbench MVP for Internet Security: www.brainbench.com
Bristol, UK Need reliable and secure network systems?
PGP/GnuPG ID:0x271fd950 http://www.assursys.com/