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Arny Krueger
Guest
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 Posted: Tue Jun 07, 2005 8:28 pm Post subject: Re: HiFi vs. Computer |
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Tim Martin wrote:
| Quote: | "Arny Krueger" <arnyk@hotpop.com> wrote in message
news:B5-dnaJC2MZQ4jjfRVn-rg@comcast.com...
What you don't seem to realize Tim is the fact that all
of
the limiations that you've been obsessing over relate to
both analog and digital signals.
That's incorrect: analog signals are continuous. Between
any two
points in time where the analog signal is changing, one
can find
another point in time where the value of the analog signal
differs
from its values at either of the first two points in time.
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That harkens back to the myth that all analog signals have
infinite resolution and infinite bandwidth.
| Quote: | This is not true for digital representations of analog
signals. |
It's just that in the digital domain, the limitations on
resolution and bandwidth are very obvious and explicit.
However, in the digital domain the resolution and bandwidth
are not limited by physical considerations other than
computational bandwidth and precision which is more readily
extenstible or managable.
| Quote: | Of course, there are limits in how accurately one can
represent analog
signals, whether the representation is digital or analog.
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That's my point.
| Quote: | But the limits are in communication channels and storage
schemes, not in the
signals themselves.
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You can always find more communcations bandwidth and storage
media. You can't extend analog dynamic range much beyond
about 130 dB, usually not more than 110 or so. |
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Tim Martin
Guest
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| Posted: Tue Jun 07, 2005 9:32 pm Post subject: Re: HiFi vs. Computer |
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"Arny Krueger" <arnyk@hotpop.com> wrote in message
news:mvGdnY6A15feVjjfRVn-rg@comcast.com...
It's also my point.
And because digital and analog representations cannot represent original
analog signals exactly, it doesn't in itself matter if we use compression
when storing those representations; what matters is whether the reproduction
of the stored data is close enough to the original analog signal to suit our
purposes.
As you say, in the digital domain, the limitations are explicit, which is
why it seemed easier to explain the point referring only to digital
representations (which are what the person mentioning compression wanted to
store anyway.) But of course exactly the same applies to analog
representations.
Tim |
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Stewart Pinkerton
Guest
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| Posted: Wed Jun 08, 2005 6:12 am Post subject: Re: HiFi vs. Computer |
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On Tue, 07 Jun 2005 17:32:46 GMT, "Tim Martin"
<tim2718281@ntlworld.com> wrote:
| Quote: | And because digital and analog representations cannot represent original
analog signals exactly,
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Sure they can, provided that the resolution and bandwidth limits of
the system exceed those of the original event. In the case of the
ubiquitous 24/96, that is a given for anything short of a military jet
doing a touch and go over the microphone at midnight in the desert!
| Quote: | it doesn't in itself matter if we use compression
when storing those representations;
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It does if we use *lossy* compression!
| Quote: | what matters is whether the reproduction
of the stored data is close enough to the original analog signal to suit our
purposes.
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Indeed, and even with 16/44, that will be the case for any music
master tape.
| Quote: | As you say, in the digital domain, the limitations are explicit, which is
why it seemed easier to explain the point referring only to digital
representations (which are what the person mentioning compression wanted to
store anyway.) But of course exactly the same applies to analog
representations.
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Indeed, except that all known analogue storage systems are inferior to
24/96 digital, and the majority are inferior to 16/44.
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
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Tim Martin
Guest
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| Posted: Wed Jun 08, 2005 12:02 pm Post subject: Re: HiFi vs. Computer |
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"Stewart Pinkerton" <patent3@dircon.co.uk> wrote in message
news:2osba118e8g7l2hbi8daj9v41qo37niast@4ax.com...
| Quote: | That's because you are ignoring reality, as in most of your posts. How
else would you produce an analogue of the original sonic event?
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I explained that. One can measure the position of a vibrating diaphragm,
Tim |
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Tim Martin
Guest
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| Posted: Wed Jun 08, 2005 12:02 pm Post subject: Re: HiFi vs. Computer |
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"Stewart Pinkerton" <patent3@dircon.co.uk> wrote in message
news:10tba1h8lpuhj674hu1a1v1n7na630d1f7@4ax.com...
| Quote: | That's incorrect: analog signals are continuous. Between any two points
in
time where the analog signal is changing, one can find another point in
time
where the value of the analog signal differs from its values at either of
the first two points in time.
Clearly, you have absolutely *no* understanding of the real physical
world. Go learn about uncertainty, before you spout such nonsense
here.
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As usual, instead of commenting on the point made, you put up a smokescreen.
However, if you think what I said is incorrect, please show it. In the case
of the bird singing in the woods, demonstrate there are two points in
time,where the analog signal in the interval between those two ponts in time
is unchanging.
Tim |
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Richard Crowley
Guest
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| Posted: Wed Jun 08, 2005 2:05 pm Post subject: Re: HiFi vs. Computer |
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"Tim Martin" <tim2718281@ntlworld.com> wrote in message
news:fGApe.1829$m4.93@newsfe3-gui.ntli.net...
| Quote: |
"Stewart Pinkerton" <patent3@dircon.co.uk> wrote in message
news:2osba118e8g7l2hbi8daj9v41qo37niast@4ax.com...
That's because you are ignoring reality, as in most of your posts.
How
else would you produce an analogue of the original sonic event?
I explained that. One can measure the position of a vibrating
diaphragm,
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Congratulations, you have re-invented the microphone.
Unfortunately for you, about 100 years too late. Some
study of history and theory really would go a long ways
toward helping you understand what is happening here
in the real world. |
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Tim Martin
Guest
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| Posted: Wed Jun 08, 2005 3:04 pm Post subject: Re: HiFi vs. Computer |
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"Richard Crowley" <rcrowley7@xprt.net> wrote in message
news:11ads6hp0chg949@corp.supernews.com...
| Quote: | Congratulations, you have re-invented the microphone.
|
I think by "microphone" people normally mean a transducer that converts
changes in air pressure into electrical signals.
It's possible to measure movement without that, and in fact there are
commercial devices using optical measurement to measure such movements.
Such devices are not generally termed "microphones".
Tim |
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Guest
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| Posted: Wed Jun 08, 2005 4:03 pm Post subject: Re: HiFi vs. Computer |
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Tim Martin wrote:
| Quote: | "Richard Crowley" <rcrowley7@xprt.net> wrote in message
news:11ads6hp0chg949@corp.supernews.com...
Congratulations, you have re-invented the microphone.
I think by "microphone" people normally mean a transducer that converts
changes in air pressure into electrical signals.
It's possible to measure movement without that, and in fact there are
commercial devices using optical measurement to measure such movements.
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And then the optical signal is converted into an electrical signal.
So what's the difference (subtle hint: NONE!)
| Quote: | Such devices are not generally termed "microphones".
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They ARE called microphones if their bandwidth is over the
audio range. If lower, they're often called "barometers." If
higher, they're called "ultrasonic detectors."
The point being, and one which, I suspect, your quite aware of
despite your obvious troll-like behavior to date, is that the
physical operating prionciple behind what you assign different
names to is utterly irrelevant semantic obfuscation on your part.
There are bascially two classes of transducers that perform these
tasks. One class includes true pressure transducers, and include
barometers and audio microphones such as some condenser microphones
and piezo microphones whose output signal is a direct function of
diaphragm position. The second class is velocity transducers,
which include anemometers and other types of audio microphones,
whose output is a function of instantaneous disphragm velocity.
The difference, for the purpose of discussion, is irrelevant,
especially since you can take the output of a pressure transducer
and differentiate it WRT time and get velocity, or take the output
of a velocity transducer and intergaret it WRT time and get position.
Your ability to drown in your own swirl of semantic two-step
continues to be a source of amusement for us all. |
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Wessel Dirksen
Guest
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| Posted: Wed Jun 08, 2005 4:03 pm Post subject: Re: HiFi vs. Computer |
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Arny Krueger schreef:
| Quote: | Laurence Payne wrote:
On Fri, 03 Jun 2005 02:19:12 GMT, "Tim Martin"
tim2718281@ntlworld.com> wrote:
An analog signal, such as a bird singing in the woods,
has infinite
bandwidth.
No it isn't. It is constrained by all sorts of physical
limitations,
both in the bird and in the environment.
Agreed. The spectral content of most natural sounds will
reveal the inevitable high end roll-off if measurered with a
mic capable of going out to about 50 KHz. In a few cases one
must go out to a few 100 KHz.
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Simpler yet, infinity is even ruled out by the very vehicle of sound
propagation itself which can never be infinite. If anything is acoustic
in nature, it can't be of infinite bandwidth otherwise it would violate
Newton's basic law of conservation of energy. To say that any "sound"
has infinite bandwidth is to say that inertia doesn't exist. |
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Tim Martin
Guest
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| Posted: Wed Jun 08, 2005 4:03 pm Post subject: Re: HiFi vs. Computer |
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<dpierce@cartchunk.org> wrote in message
news:1118245149.952932.31770@g43g2000cwa.googlegroups.com...
| Quote: | I think by "microphone" people normally mean a transducer that converts
changes in air pressure into electrical signals.
It's possible to measure movement without that, and in fact there are
commercial devices using optical measurement to measure such movements.
And then the optical signal is converted into an electrical signal.
So what's the difference (subtle hint: NONE!)
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The lack of need for generating an electrical signal from the movement of
the air may mean that one can use a detection system with physical
characteristics different from microphones.
Tim |
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Tim Martin
Guest
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| Posted: Wed Jun 08, 2005 5:05 pm Post subject: Re: HiFi vs. Computer |
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<dpierce@cartchunk.org> wrote in message
news:1118245149.952932.31770@g43g2000cwa.googlegroups.com...
Just to remind you, the point is:
"Any digital storage of an analog signal compresses it.
"That is, for any method of storing an analog signal in x bits, it is
possible to devise a digital storage mechanism using >x bits which can be
used to reproduce a more accurate rendition of the original analog signal."
Notice that the statement has nothing to do with electrical signals,
transducers and so on.
Tim |
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Guest
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| Posted: Wed Jun 08, 2005 5:05 pm Post subject: Re: HiFi vs. Computer |
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Tim Martin wrote:
| Quote: | dpierce@cartchunk.org> wrote in message
news:1118245149.952932.31770@g43g2000cwa.googlegroups.com...
Just to remind you, the point is:
"Any digital storage of an analog signal compresses it.
"That is, for any method of storing an analog signal in x bits, it is
possible to devise a digital storage mechanism using >x bits which can be
used to reproduce a more accurate rendition of the original analog signal."
Notice that the statement has nothing to do with electrical signals,
transducers and so on.
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And just to remind you, not that it did any good the last time,
that your point is just plain wrong, despite the numerous
irrelevancies and flat out nonsense you've brought to the table. |
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Stewart Pinkerton
Guest
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| Posted: Wed Jun 08, 2005 6:47 pm Post subject: Re: HiFi vs. Computer |
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On Wed, 08 Jun 2005 11:38:14 GMT, "Tim Martin"
<tim2718281@ntlworld.com> wrote:
| Quote: |
"Stewart Pinkerton" <patent3@dircon.co.uk> wrote in message
news:10tba1h8lpuhj674hu1a1v1n7na630d1f7@4ax.com...
That's incorrect: analog signals are continuous. Between any two points in
time where the analog signal is changing, one can find another point in time
where the value of the analog signal differs from its values at either of
the first two points in time.
Clearly, you have absolutely *no* understanding of the real physical
world. Go learn about uncertainty, before you spout such nonsense
here.
As usual, instead of commenting on the point made, you put up a smokescreen.
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No, you simply fail to understand the basic physics, as has been all
too obvious all along.
| Quote: | However, if you think what I said is incorrect, please show it.
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About a dozen people already have, but you appear to be too ignorant
and/or stupid to understand what is being explained to you.
| Quote: | In the case
of the bird singing in the woods, demonstrate there are two points in
time,where the analog signal in the interval between those two ponts in time
is unchanging.
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Simple, if you have *any* grasp of basic physics. There is a noise
floor in any acoustic event, whereby there is uncertainty about the
sound pressure at any moment in time. Hence, where you have a sound
such as birdsong, where a sinusoid may be assumed to be increasing as
it passes through the zero crossing point in a positive direction, the
noise floor may be moving in the opposite direction with the same
fundamental frequency at that time interval - in an entirely
unpredictable way, since it is *random* in nature. In such a case, the
sound pressure will remain constant for that time interval. Any
transducer will record an analogue signal representative of that
event, as a flat line.
BTW, will you *please* understand that the original sound is *not* an
analogue signal, it is a physical event. For God's sake at least buy a
*dictionary*, if physics texts are too difficult for you.
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
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Stewart Pinkerton
Guest
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| Posted: Wed Jun 08, 2005 6:47 pm Post subject: Re: HiFi vs. Computer |
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On Wed, 08 Jun 2005 16:39:54 GMT, "Tim Martin"
<tim2718281@ntlworld.com> wrote:
| Quote: |
dpierce@cartchunk.org> wrote in message
news:1118245149.952932.31770@g43g2000cwa.googlegroups.com...
Just to remind you, the point is:
"Any digital storage of an analog signal compresses it.
"That is, for any method of storing an analog signal in x bits, it is
possible to devise a digital storage mechanism using >x bits which can be
used to reproduce a more accurate rendition of the original analog signal."
Notice that the statement has nothing to do with electrical signals,
transducers and so on.
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Yes, and it's still bollocks, just as it was the first time you
spouted it.
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
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Stewart Pinkerton
Guest
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| Posted: Wed Jun 08, 2005 6:47 pm Post subject: Re: HiFi vs. Computer |
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On Wed, 08 Jun 2005 14:48:33 GMT, "Tim Martin"
<tim2718281@ntlworld.com> wrote:
| Quote: |
"Richard Crowley" <rcrowley7@xprt.net> wrote in message
news:11ads6hp0chg949@corp.supernews.com...
Congratulations, you have re-invented the microphone.
I think by "microphone" people normally mean a transducer that converts
changes in air pressure into electrical signals.
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Indeed they do, although some microphones such as ribbons are more
velocity-sensitive.
| Quote: | It's possible to measure movement without that, and in fact there are
commercial devices using optical measurement to measure such movements.
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Specify some. I'm well aware of such devices on machine tools, but not
in this application.
| Quote: | Such devices are not generally termed "microphones".
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They are, if they are used as sonic transducers. Basically, you have
*no* idea what you're talking about - but that's been obvious for some
time.
--
Stewart Pinkerton | Music is Art - Audio is Engineering |
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