| Author |
Message |
Andre Jute
Guest
|
 Posted:
Sat Sep 24, 2005 9:43 am Post subject:
What is digital audio? The Neddy Report. |
|
|
In the current thread "Report - 2005 London HiFi Show", Andy Evans
talks about digital audio as the wave of the future, and Patrick too
mentioned it twice already.
Can someone please explain to me what digital audio is? I haven't read
the trade magazines in a decade, so I am right out of it; please start
from scratch and don't deprive me of any riches. Is it audio made by
noughts and ones; does the entire chain to and including the speaker
become digital? I thought part of even the most rabid tubie's audio
chain was digital already, in that a CD player is a digital on-off
device as far as the laser that reads it is concerned.
TIA.
Andre Jute
|
|
| Back to top |
|
 |
Stewart Pinkerton
Guest
|
| Posted:
Sat Sep 24, 2005 2:40 pm Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
On Sat, 24 Sep 2005 14:16:24 GMT, Chris Hornbeck
<chrishornbeckremovethis@att.net> wrote:
| Quote: | On 23 Sep 2005 21:43:31 -0700, "Andre Jute" <fiultra@yahoo.com> wrote:
Can someone please explain to me what digital audio is?
Digital portions of audio equipment work with integer
numbers; analog portions work with real numbers.
|
A transparent lie, since analogue audio doesn't work with any kind of
numbers. However, since digital audio uses numbers so large that they
greatly exceed the resolution of any known analogue system, this isn't
actually a problem.
Basically, digital audio samples the incoming analogue signal many
tens of thousands of times a second, and takes a 'snapshot' of the
signal amplitude at that exact moment in time. These snapshots are
stored as digital data, and are then fed (by various means which are
irrelevant to the basic process) to a device which reconstructs the
millions of snapshots into an analogue signal once more. The important
thing is that the intervening digital process is *much* more able to
provide an exact equivalent of the original analogue input signal,
than is analogue tape or especially vinyl.
Being a digital data stream like any other compuer data, it is of
course also capable of being copied hundreds of times with *zero*
genertation loss, again very unlike analogue, which goes though at
least least six intermediate stages from microphone to speaker, with
losses at each stage.
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
|
| Back to top |
|
|
Stewart Pinkerton
Guest
|
| Posted:
Sat Sep 24, 2005 5:25 pm Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
On Sat, 24 Sep 2005 15:13:19 GMT, Chris Hornbeck
<chrishornbeckremovethis@att.net> wrote:
| Quote: | On Sat, 24 Sep 2005 14:40:08 +0000 (UTC), Stewart Pinkerton
patent3@dircon.co.uk> wrote:
Can someone please explain to me what digital audio is?
Digital portions of audio equipment work with integer
numbers; analog portions work with real numbers.
A transparent lie, since analogue audio doesn't work with any kind of
numbers. However, since digital audio uses numbers so large that they
greatly exceed the resolution of any known analogue system, this isn't
actually a problem.
I thought this would be more apparent than it seems
to be. Analog values (voltage, pressure, whatever)
are within the set of real numbers. Digital values
are within the integer number set.
Didn't mean to say that your baby was ugly, just
answering the question. There's no moral value to
number sets. Both, by the way, are infinite.
|
Nice try, but still an attempt to trot out the old 'analogue has
infinite resolution' bollocks.
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
|
| Back to top |
|
|
Chris Hornbeck
Guest
|
| Posted:
Sat Sep 24, 2005 7:16 pm Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
On 23 Sep 2005 21:43:31 -0700, "Andre Jute" <fiultra@yahoo.com> wrote:
| Quote: | Can someone please explain to me what digital audio is?
|
Digital portions of audio equipment work with integer
numbers; analog portions work with real numbers.
Good fortune,
Chris Hornbeck |
|
| Back to top |
|
|
Chris Hornbeck
Guest
|
| Posted:
Sat Sep 24, 2005 8:13 pm Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
On Sat, 24 Sep 2005 14:40:08 +0000 (UTC), Stewart Pinkerton
<patent3@dircon.co.uk> wrote:
| Quote: | Can someone please explain to me what digital audio is?
Digital portions of audio equipment work with integer
numbers; analog portions work with real numbers.
A transparent lie, since analogue audio doesn't work with any kind of
numbers. However, since digital audio uses numbers so large that they
greatly exceed the resolution of any known analogue system, this isn't
actually a problem.
|
I thought this would be more apparent than it seems
to be. Analog values (voltage, pressure, whatever)
are within the set of real numbers. Digital values
are within the integer number set.
Didn't mean to say that your baby was ugly, just
answering the question. There's no moral value to
number sets. Both, by the way, are infinite.
Good fortune,
Chris Hornbeck |
|
| Back to top |
|
|
Ruud Broens
Guest
|
| Posted:
Sun Sep 25, 2005 2:32 am Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
"Stewart Pinkerton" <patent3@dircon.co.uk> wrote in message
news:gt2bj1dnkiqmu0gju5lal82d8ouulngvhe@4ax.com...
: On Sat, 24 Sep 2005 15:13:19 GMT, Chris Hornbeck
: <chrishornbeckremovethis@att.net> wrote:
: Nice try, but still an attempt to trot out the old 'analogue has
: infinite resolution' bollocks.
: --
:
: Stewart Pinkerton | Music is Art - Audio is Engineering
...since you brought it up:
what *is* the resolution of analog, would you be wanting to claim ?
R. |
|
| Back to top |
|
|
west
Guest
|
| Posted:
Sun Sep 25, 2005 4:43 am Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
"Stewart Pinkerton" <patent3@dircon.co.uk> wrote in message
news:gt2bj1dnkiqmu0gju5lal82d8ouulngvhe@4ax.com...
| Quote: | On Sat, 24 Sep 2005 15:13:19 GMT, Chris Hornbeck
chrishornbeckremovethis@att.net> wrote:
On Sat, 24 Sep 2005 14:40:08 +0000 (UTC), Stewart Pinkerton
patent3@dircon.co.uk> wrote:
Can someone please explain to me what digital audio is?
Digital portions of audio equipment work with integer
numbers; analog portions work with real numbers.
A transparent lie, since analogue audio doesn't work with any kind of
numbers. However, since digital audio uses numbers so large that they
greatly exceed the resolution of any known analogue system, this isn't
actually a problem.
I thought this would be more apparent than it seems
to be. Analog values (voltage, pressure, whatever)
are within the set of real numbers. Digital values
are within the integer number set.
Didn't mean to say that your baby was ugly, just
answering the question. There's no moral value to
number sets. Both, by the way, are infinite.
Nice try, but still an attempt to trot out the old 'analogue has
infinite resolution' bollocks.
--
Stewart Pinkerton | Music is Art - Audio is Engineering
|
Perhaps Stewart. There is an article in the recently released "AudioXpress"
magazine about this very topic. BTW: Did you know that you have an article
in that very same issue? John, I've read most of your magazine articles and
I don't mean to embarrass you, but it's an honor & privilege to have you
associated with this NG. Keep up the very fine work.
west |
|
| Back to top |
|
|
Chris Hornbeck
Guest
|
| Posted:
Sun Sep 25, 2005 4:43 am Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
On Sat, 24 Sep 2005 17:25:28 +0000 (UTC), Stewart Pinkerton
<patent3@dircon.co.uk> wrote:
| Quote: | I thought this would be more apparent than it seems
to be. Analog values (voltage, pressure, whatever)
are within the set of real numbers. Digital values
are within the integer number set.
Didn't mean to say that your baby was ugly, just
answering the question. There's no moral value to
number sets. Both, by the way, are infinite.
Nice try, but still an attempt to trot out the old 'analogue has
infinite resolution' bollocks.
|
OK, whatever you say. So what is your definition of
the difference between analog and digital?
Chris Hornbeck |
|
| Back to top |
|
|
Stewart Pinkerton
Guest
|
| Posted:
Sun Sep 25, 2005 6:59 am Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
On Sat, 24 Sep 2005 23:32:35 +0200, "Ruud Broens" <broensr@wanadoo.nl>
wrote:
| Quote: | "Stewart Pinkerton" <patent3@dircon.co.uk> wrote in message
news:gt2bj1dnkiqmu0gju5lal82d8ouulngvhe@4ax.com...
: On Sat, 24 Sep 2005 15:13:19 GMT, Chris Hornbeck
: <chrishornbeckremovethis@att.net> wrote:
: Nice try, but still an attempt to trot out the old 'analogue has
: infinite resolution' bollocks.
..since you brought it up:
what *is* the resolution of analog, would you be wanting to claim ?
|
Standard definition - it's the smallest unique amplitude which can be
reliably detected above the wideband noise floor.
That in itself is not of much use in an audio context without knowing
the available peak signal in the same device, i.e. the dynamic range,
normally quoted in deciBels. Nowadays, the simplest shorthand is to
refer to that dynamic range in terms of its equivalent bit depth, e.g.
the very best vinyl has about 12 bits dynamic range (72dB), while the
very widest ranging music master tapes have less than 14 bit
equivalent range (84dB). CD of course has about 15.5 bits or 93dB, not
the full 16 bits due to about 1/2 LSB dither being applied to
decorrelate the noise floor from the sampling rate.
Before anyone starts rabbiting on about 'hearing below the noise
floor', this extends the available dynamic range by 10-15dB and is
achieved by narrowing the bandwidth of the noise floor to match the
narrow-band nature of our aural receptors. It should be noted that
this effect appllies to digital audio in exactly the same way that it
applies to analogue.
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
|
| Back to top |
|
|
Stewart Pinkerton
Guest
|
| Posted:
Sun Sep 25, 2005 7:05 am Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
On Sat, 24 Sep 2005 23:46:29 GMT, Chris Hornbeck
<chrishornbeckremovethis@att.net> wrote:
| Quote: | On Sat, 24 Sep 2005 17:25:28 +0000 (UTC), Stewart Pinkerton
patent3@dircon.co.uk> wrote:
I thought this would be more apparent than it seems
to be. Analog values (voltage, pressure, whatever)
are within the set of real numbers. Digital values
are within the integer number set.
Didn't mean to say that your baby was ugly, just
answering the question. There's no moral value to
number sets. Both, by the way, are infinite.
Nice try, but still an attempt to trot out the old 'analogue has
infinite resolution' bollocks.
OK, whatever you say. So what is your definition of
the difference between analog and digital?
|
In principle, there isn't one. In practice, digital audio suffers no
generation loss (very important when you consider all the intermediate
storage stages between the signal leaving the microphone and arriving
at your loudspeakers), it has no problems with full-level signals
anywhere within its frequency range, it has vanishingly nlow
distortion at all frequencies and at all signal levels, and it has
much wider dynamic range than any analogue system.
A digital audio system, and particularly when we look at the
ubiquitous 24/96 studio standard which applies all the way up to the
final mixdown master for CD (or even beyond on DVD), is in practice
limited only by the analogue parts of the system. The digital side is
utterly transparent. Of course, some people just can't let go of that
warm cuddly feeling, so you do get people asking for their
immaculately clean digital masters to be given a final pass through an
analogue tape machine to reintroduce that distortion and poise that
they've been used to all these previous years.
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
|
| Back to top |
|
|
Stewart Pinkerton
Guest
|
| Posted:
Sun Sep 25, 2005 7:12 am Post subject:
ndeed |
|
|
On Sun, 25 Sep 2005 00:38:41 GMT, "west" <westley@Tampabay.rr.com>
wrote:
| Quote: | "Stewart Pinkerton" <patent3@dircon.co.uk> wrote in message
news:gt2bj1dnkiqmu0gju5lal82d8ouulngvhe@4ax.com...
On Sat, 24 Sep 2005 15:13:19 GMT, Chris Hornbeck
chrishornbeckremovethis@att.net> wrote:
On Sat, 24 Sep 2005 14:40:08 +0000 (UTC), Stewart Pinkerton
patent3@dircon.co.uk> wrote:
Can someone please explain to me what digital audio is?
Digital portions of audio equipment work with integer
numbers; analog portions work with real numbers.
A transparent lie, since analogue audio doesn't work with any kind of
numbers. However, since digital audio uses numbers so large that they
greatly exceed the resolution of any known analogue system, this isn't
actually a problem.
I thought this would be more apparent than it seems
to be. Analog values (voltage, pressure, whatever)
are within the set of real numbers. Digital values
are within the integer number set.
Didn't mean to say that your baby was ugly, just
answering the question. There's no moral value to
number sets. Both, by the way, are infinite.
Nice try, but still an attempt to trot out the old 'analogue has
infinite resolution' bollocks.
--
Stewart Pinkerton | Music is Art - Audio is Engineering
Perhaps Stewart. There is an article in the recently released "AudioXpress"
magazine about this very topic.
|
Indeed so, and I expect modern high-speed Class D amplifiers to spread
across the home audio world at great speed. They're already used in
some 'high end' designs such as the (now pretty obsolete) Tact
Millenium mentioned in the article, and of course are at the heart of
the superb B&O Lab 5 speakers. B&O making truly high end speakers -
who'd have thought it? :-)
| Quote: | BTW: Did you know that you have an article
in that very same issue?
|
You may be confusing me with someone else.
| Quote: | John, I've read most of your magazine articles and
I don't mean to embarrass you, but it's an honor & privilege to have you
associated with this NG. Keep up the very fine work.
west
|
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
|
| Back to top |
|
|
vinylbigot
Guest
|
| Posted:
Sun Sep 25, 2005 10:38 am Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
Yes, but integers belong to the infinite set called "Aleph Null" (or the
countable infinity) while real numbers belong to a set of greater infinity.
As of yet there is no metric for determining the exact difference--only that
there is at least one infinity order greater than Aleph Null. This was
first proved rigorouly (as far as we know) by George Cantor in the 19th
century. The proof known as the "Cantor Ternary Set Method" is a standard
problem for upper level Real Variable Analysis students on the PhD math or
phsics track Cantor is also called the father of Set Theory--which led to
logical inconsistancies that were only dealt with rigorously by Einstien's
friend Max Godel.
Thus, mathematically speaking, the digital domain is far less exact than the
analog domain.
Of course, the real level of exactness is determnined in the digital domain
by the rate of sampling and in the analog domain by the maximum frequency
content of the sample stored. 24 bit 196KHz sampling in the studio has a
theoretical Nyquist limit equal to approximately the analog content stored
in the best technologies--about 100HKz. Of course the digital domain has
the further problem true undistorted content for non-steady state signals
(which is required for the infinite filters in the Nyquist limit) that
limits the pure mathematical content--undistorted--to about 50 KHz at 24
bits and 20KHz at 16 bit in the studio example above.
| Quote: | Didn't mean to say that your baby was ugly, just
answering the question. There's no moral value to
number sets. Both, by the way, are infinite.
Good fortune,
Chris Hornbeck |
|
|
| Back to top |
|
|
Ruud Broens
Guest
|
| Posted:
Mon Sep 26, 2005 3:32 am Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
"Stewart Pinkerton" <patent3@dircon.co.uk> wrote in message
news:okicj15htltc02om9l19vb61nigf1bu181@4ax.com...
: On Sat, 24 Sep 2005 23:46:29 GMT, Chris Hornbeck
: <chrishornbeckremovethis@att.net> wrote:
:
: >On Sat, 24 Sep 2005 17:25:28 +0000 (UTC), Stewart Pinkerton
: ><patent3@dircon.co.uk> wrote:
: >
: >>>I thought this would be more apparent than it seems
: >>>to be. Analog values (voltage, pressure, whatever)
: >>>are within the set of real numbers. Digital values
: >>>are within the integer number set.
: >>>
: >>>Didn't mean to say that your baby was ugly, just
: >>>answering the question. There's no moral value to
: >>>number sets. Both, by the way, are infinite.
: >>
: >>Nice try, but still an attempt to trot out the old 'analogue has
: >>infinite resolution' bollocks.
: >
: >OK, whatever you say. So what is your definition of
: >the difference between analog and digital?
:
: In principle, there isn't one. In practice, digital audio suffers no
: generation loss (very important when you consider all the intermediate
: storage stages between the signal leaving the microphone and arriving
: at your loudspeakers), it has no problems with full-level signals
: anywhere within its frequency range, it has vanishingly nlow
: distortion at all frequencies and at all signal levels, and it has
: much wider dynamic range than any analogue system.
:
: A digital audio system, and particularly when we look at the
: ubiquitous 24/96 studio standard which applies all the way up to the
: final mixdown master for CD (or even beyond on DVD), is in practice
: limited only by the analogue parts of the system. The digital side is
: utterly transparent. Of course, some people just can't let go of that
: warm cuddly feeling, so you do get people asking for their
: immaculately clean digital masters to be given a final pass through an
: analogue tape machine to reintroduce that distortion and poise that
: they've been used to all these previous years.
: --
:
: Stewart Pinkerton | Music is Art - Audio is Engineering
That's all fine 'n dandy, Stewart,
but let's see if what you give as a response makes sense:
Analog values (voltage, pressure, whatever)
are within the set of real numbers. Digital values
are within the integer number set.-->
| Quote: | Nice try, but still an attempt to trot out the old 'analogue has
infinite resolution' bollocks
yeah, great rebuttal, there :-) noted |
So what is your definition of
the difference between analog and digital?-->
| Quote: | In principle, there isn't one.
|
youse call *that* definition, scott-side ?
straw man about digital recording and producing
having nada, zip, nonwhatso-ever to do with
the analogue digital difference, just a
summation of an implementation
and the nicceties we can do with 'm,
noted.
Rudy |
|
| Back to top |
|
|
Phil Allison
Guest
|
| Posted:
Mon Sep 26, 2005 2:12 pm Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
"vinylbigot" = a grossly autistic menace
(snip pseudo mathematical drivel)
| Quote: | Thus, mathematically speaking, the digital domain is far less exact than
the analog domain.
|
** A complete irrelevance even - if it were true.
| Quote: | Of course, the real level of exactness is determnined in the digital
domain by the rate of sampling and in the analog domain by the maximum
frequency content of the sample stored.
|
** Wrong on both counts.
Frequency is only one element of an audio signal.
| Quote: | 24 bit 196KHz sampling in the studio has a theoretical Nyquist limit
equal to approximately the analog content stored in the best
technologies--about 100HKz.
|
** More asinine drivel best technologies = what ??
A wiggly channel scraped into a piece of plastic ???
( snip even more stomach churning crapology)
Puke, puke .....
............... Phil |
|
| Back to top |
|
|
Stewart Pinkerton
Guest
|
| Posted:
Mon Sep 26, 2005 6:11 pm Post subject:
Re: What is digital audio? The Neddy Report. |
|
|
On Sat, 24 Sep 2005 22:38:02 -0700, "vinylbigot"
<vinylbigot@comcast.net> wrote:
| Quote: | Yes, but integers belong to the infinite set called "Aleph Null" (or the
countable infinity) while real numbers belong to a set of greater infinity.
As of yet there is no metric for determining the exact difference--only that
there is at least one infinity order greater than Aleph Null. This was
first proved rigorouly (as far as we know) by George Cantor in the 19th
century. The proof known as the "Cantor Ternary Set Method" is a standard
problem for upper level Real Variable Analysis students on the PhD math or
phsics track Cantor is also called the father of Set Theory--which led to
logical inconsistancies that were only dealt with rigorously by Einstien's
friend Max Godel.
Thus, mathematically speaking, the digital domain is far less exact than the
analog domain.
|
Only once you get infinitely far from reality.............
| Quote: | Of course, the real level of exactness is determnined in the digital domain
by the rate of sampling and in the analog domain by the maximum frequency
content of the sample stored.
|
Utter (and ignorant) rubbish, as one might expect from a vinyl bigot.
Exactness is a measure of amplitude, not of frequency. The
*information content* is of course a function of both dynamic range
*and* bandwidth. Frequency range alone is perhaps the least important
aspect of the comparison.
| Quote: | 24 bit 196KHz sampling in the studio has a
theoretical Nyquist limit equal to approximately the analog content stored
in the best technologies--about 100HKz.
|
It's 192k, and the Nyquist limit is just below 96kHz. Furthermore,
regardless of the 50kHz or so bandwidth of 30ips studio master tapes
(although not the commonly used large capsule condenser microphones,
of course.......), nothing above 20kHz or so makes it onto vinyl
anyway, and almost averything above 15kHz is just noise.
| Quote: | Of course the digital domain has
the further problem true undistorted content for non-steady state signals
(which is required for the infinite filters in the Nyquist limit) that
limits the pure mathematical content--undistorted--to about 50 KHz at 24
bits and 20KHz at 16 bit in the studio example above.
|
More ignorant rubbish - the bit depth has nothing whatever to do with
the frequency range. Further, modern systems are beautifully linear up
to more than 90kHz for 192k sampling, and close to 21kHz for 44.1k
sampling. Vinyl of course rolls off above 12-15kHz and below 40Hz, so
there really is no comparison at all in the real world.
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
|
| Back to top |
|
|
|
|
|
|
Profile
Log in to check your private messages
Log in