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  #1   Report Post  
Sam
 
Posts: n/a
Default Loudspeaker timing

Many loudspeakers incorporate some type of time alighnment scheme in
their design such as a sloping baffle. Is this truly necessary? Can
people actually perceive the difference in speed between high
frequencies and low frequencies? When you listen to a live orchestra
do you hear the bass drum before you hear a high from a flute? Can
someone explain to me the significance of pace, rhythm, and timing in
our audio playback systems

Sam
  #2   Report Post  
Bob Morein
 
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Default Loudspeaker timing


"Sam" wrote in message
om...
Many loudspeakers incorporate some type of time alighnment scheme in
their design such as a sloping baffle. Is this truly necessary? Can
people actually perceive the difference in speed between high
frequencies and low frequencies? When you listen to a live orchestra
do you hear the bass drum before you hear a high from a flute?


No, you don't. That's the point of time alignment.
Can
someone explain to me the significance of pace, rhythm, and timing in
our audio playback systems

Sam


Preface:
A sloping baffle by itself does not provide time alignment.
It must be combined with a 1st order crossover.
For example, NEAR 50 speakers, with a sloping baffle, are not time aligned.

Argument:
It is highly debated.
The output of a square pulse as rendered by a time aligned speaker looks
like a square pulse. Other designs render it as two or three unrecognizable
waveforms, mysteriously percieved by most people to be the same.

Many studies claim that the ear is insensitive to time delay.
Others claim that the last iota of imaging quality is provided by this
method.
Yet time alignment exists only if the listener positions himself at one spot
in space.
The Spica TC-50 and TC-60 were perhaps the first speakers to popularize time
alignment.
But whether the time alignment, or the 1st order crossover, or the felt
covering the baffle, or a combination of all these things is responsible for
the image clarity, is subject to debate.

Time aligned speakers have low power handling capacity, as a consequence of
the 1st order crossover. Hence they are not suitable for listening at
greater than moderate volume.


  #3   Report Post  
Bob Morein
 
Posts: n/a
Default Loudspeaker timing


"Brian l. McCarty" wrote in message
ws.com...
On 29/9/03 14:27, in article
, "Sam"


wrote:

Many loudspeakers incorporate some type of time alighnment scheme in
their design such as a sloping baffle. Is this truly necessary?


Nope. For the theory to be accurate, you'd have to sit in one very
precisely measure location, and never move your head even a millimeter.

It
makes good marketing copy, however.

Not true.
According to Blauert
(
http://www.iis.ee.ic.ac.uk/~frank/su.../sl9/main.html),
the ear is able to break up the fine structure of the signal for frequencies
between 20 and 1600 Hz.
At 1600 Hz, the wavlength is about 8 inches, which means that if a listener
positions his head within a lateral plus or minus 4 inch range, his ear will
percieve a time-coherent signal.

Above 1600 Hz, the ear is believed to rely on intensity, ie., "envelope"
information for sound localization. It is this observation which inspires
the belief that the ear is insensitive to phase information.

However, the ear is sensitive, at least for simple pulses, to intra aural
time delays as small as 6 microseconds.


  #7   Report Post  
Lionel
 
Posts: n/a
Default Loudspeaker timing

Bob Morein wrote:
"Lionel" wrote in message
...

Brian l. McCarty wrote:

On 29/9/03 14:27, in article
, "Sam"




wrote:



Many loudspeakers incorporate some type of time alighnment scheme in
their design such as a sloping baffle. Is this truly necessary?


Nope. For the theory to be accurate, you'd have to sit in one very
precisely measure location, and never move your head even a millimeter.


It

makes good marketing copy, however.



Can
people actually perceive the difference in speed between high
frequencies and low frequencies?


Nope.


I think you have the answer. Time alignment has long been repudiated as
speaker designer snake oil.




Sir, I just want to say that you are a *jerk*. ;-)

Lionel


It's a rare opportunity to address Brian personally.
I second Lionel's opinion.
You are a *jerk*.



I know it's really mesquin and vain but sometime vengeance is as good as
a fresh beer. ;-)

  #8   Report Post  
Arny Krueger
 
Posts: n/a
Default Loudspeaker timing

"Sam" wrote in message
om

Many loudspeakers incorporate some type of time alignment scheme in
their design such as a sloping baffle. Is this truly necessary?


No, because the same goal, which is time-alignment of the drivers at the
crossover points, can also be accomplished by means design of the of the
crossovers.

Can people actually perceive the difference in speed between high
frequencies and low frequencies?


I don't think you are saying what you intended to say. There's no difference
in speed between high and low frequencies, but there can be a difference in
relative timing of signals. Yes, differences in time alignment can be heard,
but at higher frequencies they are mostly heard due to frequency response
variations that they cause. If equal-sized signals from the woofer and
tweeter aren't time-aligned around the usual crossover point of say, 3 KHz,
they won't add up properly to give flat response.

When you listen to a live orchestra
do you hear the bass drum before you hear a high from a flute?


Only if he bass drum plays first! But that's not the problem that stepped or
sloped baffles are trying to address.

I think you really need to think this through. The bass drum and the flute
in an orchestra aren't that well synchronized because the players are
usually so far apart. The players are humans and they synchronize to each
other based on their hearing, which includes significant delays as sound
travels across the stage and as their reflexes take finite amounts of time.

The bass drum is usually someplace near the center or left back, while the
flute player is closer to the center-right front. The flute player is closer
to the listener if the listener is in the center of the room, but if the
listener is to the far left, the bass drum player might be closer or at a
similar difference. Bottom line, the differences in distance in the concert
hall are usually measured in feet, while the differences in distance due to
the design of speaker enclosures is probably a foot or less. The speed of
sound is basically constant, so the differences in timings due to locations
of musicians in the concert hall and the differences in timings due to
locations of speaker drivers in enclosures are vastly different.

From the standpoint of the microphones that are used to record, there are
timing differences measured in many milliseconds among the various
instruments in an orchestra. If you look at speaker drivers on a flat baffle
board, the timing differences due to mounting the speakers (all within one
foot) are probably less than a millisecond. Not to be compared!

Can someone explain to me the significance of pace, rhythm, and timing in
our audio playback systems


Wrong criteria, all of them. See my former comments about smooth, flat
frequency response. Ironically sloped and stepped baffles can also add
frequency response variations due to effects like diffraction.

The idea of time-aligning speakers traces back to sound stages in Hollywood
in the 1930s. The monitor speakers of the day were based on horns, and there
were path differences between woofers and tweeters, sometimes of many feet.
These were due to the differences in the design of the woofers and tweeters.
Timing could vary by 3-10 milliseconds or more. Sharp sounds like tap
dancing were observed to be undesirably changed and highly colored by those
time differences. Because the differences were so gross, they were important
concerns.

In contrast, consider a modern 2-way speaker with a 8" or smaller woofer and
a dome tweeter. The path difference might be 6 inches or less. Timing due to
path length differences are less than a millisecond. This is an entirely
different kind of perception than those due to timing differences or 5 or 10
milliseconds.



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Arny Krueger
 
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Default Loudspeaker timing

"Bob Morein" wrote in message
ws.com \

This would be a forged post from Brian McCartey.

Headers:

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Date: Mon, 29 Sep 2003 10:22:00 GMT
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Subject: Loudspeaker timing
From: Bob Morein
Newsgroups: rec.audio.opinion
References:

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Headers from a *real* Bob Morien post:

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NNTP-Posting-Date: Mon, 29 Sep 2003 01:58:55 -0500
Reply-To: "Bob Morein"
From: "Bob Morein"
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References:
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Subject: Loudspeaker timing
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action: forward to the australian ISP.


On 29/9/03 19:36, in article
, "Arny
Krueger" wrote:

I think you really need to think this through. The bass drum and the
flute in an orchestra aren't that well synchronized because the
players are usually so far apart


I think it's YOU that needs to think this through. The bass drum and
flute are perfectly synchronized because the players are
professionals that are trained to follow not just audio cues but a
conductor.

Please don't offer opinions in areas you have no competence.
Whatever that might be.


Bob Morein
--


http://www.ledger-enquirer.com/mld/l...ws/4853918.htm

Doctoral student takes intellectual property case to Supreme Court
By L. STUART DITZEN
Philadelphia Inquirer

PHILADELPHIA -Even the professors who dismissed him from a doctoral
program at Drexel University agreed that Robert Morein was
uncommonly smart.

They apparently didn't realize that he was uncommonly stubborn too -
so much so that he would mount a court fight all the way to the U.S.
Supreme Court to challenge his dismissal.


The Supremes have already rejected this appeal, btw.

"It's a personality trait I have - I'm a tenacious guy," said
Morein, a pleasantly eccentric man regarded by friends as an
inventive genius. "And we do come to a larger issue here."


An "inventive genius" that has never invented anything. And hardly
"pleasantly" eccentric.

A five-year legal battle between this unusual ex-student and one of
Philadelphia's premier educational institutions has gone largely
unnoticed by the media and the public.


Because no one gives a **** about a 50 year old loser.

But it has been the subject of much attention in academia.

Drexel says it dismissed Morein in 1995 because he failed, after
eight years, to complete a thesis required for a doctorate in
electrical and computer engineering.


Not to mention the 12 years it took him to get thru high school!
BWAAAAAAHAHAHAHAHAHAHAHAHA!


Morein, 50, of Dresher, Pa., contends that he was dismissed only
after his thesis adviser "appropriated" an innovative idea Morein
had developed in a rarefied area of thought called "estimation
theory" and arranged to have it patented.


A contention rejected by three courts. From a 50 YEAR OLD that has
done NOTHING PRODUCTIVE with his life.


In February 2000, Philadelphia Common Pleas Court Judge Esther R.
Sylvester ruled that Morein's adviser indeed had taken his idea.


An idea that was worth nothing, because it didn't work. Just like
Robert Morein, who has never worked a day in his life.


Sylvester held that Morein had been unjustly dismissed and she
ordered Drexel to reinstate him or refund his tuition.


Funnily enough, Drexel AGREED to reinstate Morein, who rejected the
offer because he knew he was and IS a failed loser. Spending daddy's
money to cover up his lack of productivity.

That brought roars of protest from the lions of academia. There is a
long tradition in America of noninterference by the courts in
academic decisions.

Backed by every major university in Pennsylvania and organizations
representing thousands of others around the country, Drexel appealed
to the state Superior Court.

The appellate court, by a 2-1 vote, reversed Sylvester in June 2001
and restored the status quo. Morein was, once again, out at Drexel.
And the time-honored axiom that courts ought to keep their noses out
of academic affairs was reasserted.

The state Supreme Court declined to review the case and, in an
ordinary litigation, that would have been the end of it.

But Morein, in a quixotic gesture that goes steeply against the
odds, has asked the highest court in the land to give him a hearing.


Daddy throws more money down the crapper.

His attorney, Faye Riva Cohen, said the Supreme Court appeal is
important even if it fails because it raises the issue of whether a
university has a right to lay claim to a student's ideas - or
intellectual property - without compensation.

"Any time you are in a Ph.D. program, you are a serf, you are a
slave," said Cohen. Morein "is concerned not only for himself. He
feels that what happened to him is pretty common."


It's called HIGHER EDUCATION, honey. The students aren't in charge,
the UNIVERSITY and PROFESSORS are.


Drexel's attorney, Neil J. Hamburg, called Morein's appeal - and his
claim that his idea was stolen - "preposterous."

"I will eat my shoe if the Supreme Court hears this case," declared
Hamburg. "We're not even going to file a response. He is a brilliant
guy, but his intelligence should be used for the advancement of
society rather than pursuing self-destructive litigation."


No **** sherlock.

The litigation began in 1997, when Morein sued Drexel claiming that a
committee of professors had dumped him after he accused his faculty
adviser, Paul Kalata, of appropriating his idea.

His concept was considered to have potential value for businesses in
minutely measuring the internal functions of machines, industrial
processes and electronic systems.

The field of "estimation theory" is one in which scientists attempt
to calculate what they cannot plainly observe, such as the inside
workings of a nuclear plant or a computer.


My estimation theory? There is NO brain at work inside the head of
Robert Morein, only sawdust.


Prior to Morein's dismissal, Drexel looked into his complaint
against Kalata and concluded that the associate professor had done
nothing wrong. Kalata, through a university lawyer, declined to
comment.

At a nonjury trial before Sylvester in 1999, Morein testified that
Kalata in 1990 had posed a technical problem for him to study for
his thesis. It related to estimation theory.

Kalata, who did not appear at the trial, said in a 1998 deposition
that a Cherry Hill company for which he was a paid consultant, K-Tron
International, had asked him to develop an alternate estimation
method for it. The company manufactures bulk material feeders and
conveyors used in industrial processes.

Morein testified that, after much study, he experienced "a flash of
inspiration" and came up with a novel mathematical concept to
address the problem Kalata had presented.

Without his knowledge, Morein said, Kalata shared the idea with
K-Tron.

K-Tron then applied for a patent, listing Kalata and Morein as
co-inventors.

Morein said he agreed "under duress" to the arrangement, but felt
"locked into a highly disadvantageous situation." As a result, he
testified, he became alienated from Kalata.

As events unfolded, Kalata signed over his interest in the patent to
K-Tron. The company never capitalized on the technology and
eventually allowed the patent to lapse. No one made any money from
it.


Because it was bogus. Even Kalata was mortified that he was a victim
of this SCAMSTER, Robert Morein.

In 1991, Morein went to the head of Drexel's electrical engineering
department, accused Kalata of appropriating his intellectual
property, and asked for a new faculty adviser.


The staff at Drexel laughed wildly at the ignorance of Robert Morein.

He didn't get one. Instead, a committee of four professors, including
Kalata, was formed to oversee Morein's thesis work.

Four years later, the committee dismissed him, saying he had failed
to complete his thesis.


So Morein ****s up his first couple years, gets new faculty advisers
(a TEAM), and then ****s up again! Brilliant!


Morein claimed that the committee intentionally had undermined him.


Morein makes LOTS of claims that are nonsense. One look thru the
usenet proves it.


Judge Sylvester agreed. In her ruling, Sylvester wrote: "It is this
court's opinion that the defendants were motivated by bad faith and
ill will."


So much for political machine judges.

The U.S. Supreme Court receives 7,000 appeals a year and agrees to
hear only about 100 of them.

Hamburg, Drexel's attorney, is betting the high court will reject
Morein's appeal out of hand because its focal point - concerning a
student's right to intellectual property - was not central to the
litigation in the Pennsylvania courts.


Morein said he understands it's a long shot, but he feels he must
pursue it.


Just like all the failed "causes" Morein pursues. Heck, he's been
chasing another "Brian McCarty" for years and yet has ZERO impact on
anything.

Failure. Look it up in Websters. You'll see a picture of Robert
Morein. The poster boy for SCAMMING LOSERS.


"I had to seek closure," he said.

Without a doctorate, he said, he has been unable to pursue a career
he had hoped would lead him into research on artificial intelligence.


Who better to tell us about "artificial intelligence".
BWAAAAAAAAAHAHAHAHAHAHAHAHAHAHA!


As it is, Morein lives at home with his father and makes a modest
income from stock investments. He has written a film script that he
is trying to make into a movie. And in the basement of his father's
home he is working on an invention, an industrial pump so powerful
it could cut steel with a bulletlike stream of water.



FAILED STUDENT
FAILED MOVIE MAKER
FAILED SCREENWRITER
FAILED INVESTOR
FAILED DRIVER
FAILED SON
FAILED PARENTS
FAILED INVENTOR
FAILED PLAINTIFF
FAILED HOMOSEXUAL
FAILED HUMAN
FAILED
FAILED

But none of it is what he had imagined for himself.

"I don't really have a replacement career," Morein said. "It's a very
gnawing thing."



  #10   Report Post  
Bob Morein
 
Posts: n/a
Default Loudspeaker timing

On 29/9/03 19:36, in article , "Arny
Krueger" wrote:

I think you really need to think this through. The bass drum and the flute
in an orchestra aren't that well synchronized because the players are
usually so far apart


I think it's YOU that needs to think this through. The bass drum and flute
are perfectly synchronized because the players are professionals that are
trained to follow not just audio cues but a conductor.

Please don't offer opinions in areas you have no competence. Whatever that
might be.


Bob Morein
--


http://www.ledger-enquirer.com/mld/l...ws/4853918.htm

Doctoral student takes intellectual property case to Supreme Court
By L. STUART DITZEN
Philadelphia Inquirer

PHILADELPHIA -Even the professors who dismissed him from a doctoral program
at Drexel University agreed that Robert Morein was uncommonly smart.

They apparently didn't realize that he was uncommonly stubborn too - so much
so that he would mount a court fight all the way to the U.S. Supreme Court
to challenge his dismissal.


The Supremes have already rejected this appeal, btw.

"It's a personality trait I have - I'm a tenacious guy," said Morein, a
pleasantly eccentric man regarded by friends as an inventive genius. "And we
do come to a larger issue here."


An "inventive genius" that has never invented anything. And hardly
"pleasantly" eccentric.

A five-year legal battle between this unusual ex-student and one of
Philadelphia's premier educational institutions has gone largely unnoticed
by the media and the public.


Because no one gives a **** about a 50 year old loser.

But it has been the subject of much attention in academia.

Drexel says it dismissed Morein in 1995 because he failed, after eight
years, to complete a thesis required for a doctorate in electrical and
computer engineering.


Not to mention the 12 years it took him to get thru high school!
BWAAAAAAHAHAHAHAHAHAHAHAHA!


Morein, 50, of Dresher, Pa., contends that he was dismissed only after his
thesis adviser "appropriated" an innovative idea Morein had developed in a
rarefied area of thought called "estimation theory" and arranged to have it
patented.


A contention rejected by three courts. From a 50 YEAR OLD that has
done NOTHING PRODUCTIVE with his life.


In February 2000, Philadelphia Common Pleas Court Judge Esther R. Sylvester
ruled that Morein's adviser indeed had taken his idea.


An idea that was worth nothing, because it didn't work. Just like
Robert Morein, who has never worked a day in his life.


Sylvester held that Morein had been unjustly dismissed and she ordered
Drexel to reinstate him or refund his tuition.


Funnily enough, Drexel AGREED to reinstate Morein, who rejected the
offer because he knew he was and IS a failed loser. Spending daddy's
money to cover up his lack of productivity.

That brought roars of protest from the lions of academia. There is a long
tradition in America of noninterference by the courts in academic decisions.

Backed by every major university in Pennsylvania and organizations
representing thousands of others around the country, Drexel appealed to the
state Superior Court.

The appellate court, by a 2-1 vote, reversed Sylvester in June 2001 and
restored the status quo. Morein was, once again, out at Drexel. And the
time-honored axiom that courts ought to keep their noses out of academic
affairs was reasserted.

The state Supreme Court declined to review the case and, in an ordinary
litigation, that would have been the end of it.

But Morein, in a quixotic gesture that goes steeply against the odds, has
asked the highest court in the land to give him a hearing.


Daddy throws more money down the crapper.

His attorney, Faye Riva Cohen, said the Supreme Court appeal is important
even if it fails because it raises the issue of whether a university has a
right to lay claim to a student's ideas - or intellectual property - without
compensation.

"Any time you are in a Ph.D. program, you are a serf, you are a slave," said
Cohen. Morein "is concerned not only for himself. He feels that what
happened to him is pretty common."


It's called HIGHER EDUCATION, honey. The students aren't in charge,
the UNIVERSITY and PROFESSORS are.


Drexel's attorney, Neil J. Hamburg, called Morein's appeal - and his claim
that his idea was stolen - "preposterous."

"I will eat my shoe if the Supreme Court hears this case," declared Hamburg.
"We're not even going to file a response. He is a brilliant guy, but his
intelligence should be used for the advancement of society rather than
pursuing self-destructive litigation."


No **** sherlock.

The litigation began in 1997, when Morein sued Drexel claiming that a
committee of professors had dumped him after he accused his faculty adviser,
Paul Kalata, of appropriating his idea.

His concept was considered to have potential value for businesses in
minutely measuring the internal functions of machines, industrial processes
and electronic systems.

The field of "estimation theory" is one in which scientists attempt to
calculate what they cannot plainly observe, such as the inside workings of a
nuclear plant or a computer.


My estimation theory? There is NO brain at work inside the head of
Robert Morein, only sawdust.


Prior to Morein's dismissal, Drexel looked into his complaint against Kalata
and concluded that the associate professor had done nothing wrong. Kalata,
through a university lawyer, declined to comment.

At a nonjury trial before Sylvester in 1999, Morein testified that Kalata in
1990 had posed a technical problem for him to study for his thesis. It
related to estimation theory.

Kalata, who did not appear at the trial, said in a 1998 deposition that a
Cherry Hill company for which he was a paid consultant, K-Tron
International, had asked him to develop an alternate estimation method for
it. The company manufactures bulk material feeders and conveyors used in
industrial processes.

Morein testified that, after much study, he experienced "a flash of
inspiration" and came up with a novel mathematical concept to address the
problem Kalata had presented.

Without his knowledge, Morein said, Kalata shared the idea with K-Tron.

K-Tron then applied for a patent, listing Kalata and Morein as co-inventors.

Morein said he agreed "under duress" to the arrangement, but felt "locked
into a highly disadvantageous situation." As a result, he testified, he
became alienated from Kalata.

As events unfolded, Kalata signed over his interest in the patent to K-Tron.
The company never capitalized on the technology and eventually allowed the
patent to lapse. No one made any money from it.


Because it was bogus. Even Kalata was mortified that he was a victim
of this SCAMSTER, Robert Morein.

In 1991, Morein went to the head of Drexel's electrical engineering
department, accused Kalata of appropriating his intellectual property, and
asked for a new faculty adviser.


The staff at Drexel laughed wildly at the ignorance of Robert Morein.

He didn't get one. Instead, a committee of four professors, including
Kalata, was formed to oversee Morein's thesis work.

Four years later, the committee dismissed him, saying he had failed to
complete his thesis.


So Morein ****s up his first couple years, gets new faculty advisers
(a TEAM), and then ****s up again! Brilliant!


Morein claimed that the committee intentionally had undermined him.


Morein makes LOTS of claims that are nonsense. One look thru the
usenet proves it.


Judge Sylvester agreed. In her ruling, Sylvester wrote: "It is this court's
opinion that the defendants were motivated by bad faith and ill will."


So much for political machine judges.

The U.S. Supreme Court receives 7,000 appeals a year and agrees to hear only
about 100 of them.

Hamburg, Drexel's attorney, is betting the high court will reject Morein's
appeal out of hand because its focal point - concerning a student's right to
intellectual property - was not central to the litigation in the
Pennsylvania courts.


Morein said he understands it's a long shot, but he feels he must pursue it.


Just like all the failed "causes" Morein pursues. Heck, he's been
chasing another "Brian McCarty" for years and yet has ZERO impact on
anything.

Failure. Look it up in Websters. You'll see a picture of Robert
Morein. The poster boy for SCAMMING LOSERS.


"I had to seek closure," he said.

Without a doctorate, he said, he has been unable to pursue a career he had
hoped would lead him into research on artificial intelligence.


Who better to tell us about "artificial intelligence".
BWAAAAAAAAAHAHAHAHAHAHAHAHAHAHA!


As it is, Morein lives at home with his father and makes a modest income
from stock investments. He has written a film script that he is trying to
make into a movie. And in the basement of his father's home he is working on
an invention, an industrial pump so powerful it could cut steel with a
bulletlike stream of water.



FAILED STUDENT
FAILED MOVIE MAKER
FAILED SCREENWRITER
FAILED INVESTOR
FAILED DRIVER
FAILED SON
FAILED PARENTS
FAILED INVENTOR
FAILED PLAINTIFF
FAILED HOMOSEXUAL
FAILED HUMAN
FAILED
FAILED

But none of it is what he had imagined for himself.

"I don't really have a replacement career," Morein said. "It's a very
gnawing thing."






  #11   Report Post  
Bob Morein
 
Posts: n/a
Default Loudspeaker timing


"Arny Krueger" wrote in message
...
"Bob Morein" wrote in message
ws.com \

This would be a forged post from Brian McCartey.

Yes, it would be forged.
And you have my rare compliment on a good exposition.


  #12   Report Post  
Bob Morein
 
Posts: n/a
Default Loudspeaker timing


"Lionel" wrote in message
...
Bob Morein wrote:
"Lionel" wrote in message
...

Brian l. McCarty wrote:

On 29/9/03 14:27, in article
, "Sam"




wrote:



Many loudspeakers incorporate some type of time alighnment scheme in
their design such as a sloping baffle. Is this truly necessary?


Nope. For the theory to be accurate, you'd have to sit in one very
precisely measure location, and never move your head even a millimeter.


It

makes good marketing copy, however.



Can
people actually perceive the difference in speed between high
frequencies and low frequencies?


Nope.


I think you have the answer. Time alignment has long been repudiated

as
speaker designer snake oil.




Sir, I just want to say that you are a *jerk*. ;-)

Lionel


It's a rare opportunity to address Brian personally.
I second Lionel's opinion.
You are a *jerk*.



I know it's really mesquin and vain but sometime vengeance is as good as
a fresh beer. ;-)

You know it, bud!


  #14   Report Post  
dave weil
 
Posts: n/a
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On Mon, 29 Sep 2003 07:07:02 GMT, "Brian l. McCarty"
wrote:

Can
people actually perceive the difference in speed between high
frequencies and low frequencies?


Nope.


Obviously Brian has never attended a live music event in a large hall.
  #15   Report Post  
Arny Krueger
 
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"dave weil" wrote in message
news
On Mon, 29 Sep 2003 07:07:02 GMT, "Brian l. McCarty"
wrote:

Can
people actually perceive the difference in speed between high
frequencies and low frequencies?


Nope.


Obviously Brian has never attended a live music event in a large hall.


Lovely. Weil re-writes the laws of physics to read that the speed of sound
is significantly and perceptibly dependent on frequency.

Singh lets Weil pretend to review one of his POS speakers, and now Weil is
rewriting physics books!

LOL!




  #16   Report Post  
dave weil
 
Posts: n/a
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On Mon, 29 Sep 2003 09:59:59 -0400, "Arny Krueger"
wrote:

"dave weil" wrote in message
news
On Mon, 29 Sep 2003 07:07:02 GMT, "Brian l. McCarty"
wrote:

Can
people actually perceive the difference in speed between high
frequencies and low frequencies?

Nope.


Obviously Brian has never attended a live music event in a large hall.


Lovely. Weil re-writes the laws of physics to read that the speed of sound
is significantly and perceptibly dependent on frequency.

Singh lets Weil pretend to review one of his POS speakers, and now Weil is
rewriting physics books!

LOL!


Obviously, *you* haven't been paying attention in church.

  #17   Report Post  
normanstrong
 
Posts: n/a
Default Loudspeaker timing


"dave weil" wrote in message
news
On Mon, 29 Sep 2003 07:07:02 GMT, "Brian l. McCarty"
wrote:

Can
people actually perceive the difference in speed between high
frequencies and low frequencies?


Nope.


Obviously Brian has never attended a live music event in a large

hall.

I don't believe that the speed of sound is frequency dependent. If it
was, an octave would only be in tune at a specific distance, which we
know is not the case.

Norm Strong


  #18   Report Post  
The Devil
 
Posts: n/a
Default Loudspeaker timing

On Mon, 29 Sep 2003 09:59:59 -0400, "Arny Krueger"
wrote:

Singh lets Weil pretend to review one of his POS speakers, and now Weil is
rewriting physics books!


I know I'm going to regret asking this, but why exactly do you think
dave would fake a review of Greg's speakers?

LOL!


Lies Oh Lies.

--
td
  #19   Report Post  
Bob Morein
 
Posts: n/a
Default Loudspeaker timing


"dave weil" wrote in message
news
On Mon, 29 Sep 2003 07:07:02 GMT, "Brian l. McCarty"
wrote:

Can
people actually perceive the difference in speed between high
frequencies and low frequencies?


Nope.


Obviously Brian has never attended a live music event in a large hall.


He probably has.
He plays or played multiple musical instruments.
Although he is currently insane, he may have been fairly normal earlier in
life.


  #20   Report Post  
Bob Morein
 
Posts: n/a
Default Loudspeaker timing


"dave weil" wrote in message
news
On Mon, 29 Sep 2003 07:07:02 GMT, "Brian l. McCarty"
wrote:

Can
people actually perceive the difference in speed between high
frequencies and low frequencies?


Nope.


Obviously Brian has never attended a live music event in a large hall.


You may be confused by the fact that reverberation is frequency dependent.
However, the speed of propagation of sound is not:
http://www.physics.utoronto.ca/~marj...ics/LinPP.html




  #21   Report Post  
trotsky
 
Posts: n/a
Default Loudspeaker timing

Arny Krueger wrote:

"dave weil" wrote in message
news
On Mon, 29 Sep 2003 07:07:02 GMT, "Brian l. McCarty"
wrote:


Can
people actually perceive the difference in speed between high
frequencies and low frequencies?

Nope.


Obviously Brian has never attended a live music event in a large hall.



Lovely. Weil re-writes the laws of physics to read that the speed of sound
is significantly and perceptibly dependent on frequency.

Singh lets Weil pretend to review one of his POS speakers, and now Weil is
rewriting physics books!

LOL!




I'm laughing too, at your supposed religious beliefs!

  #25   Report Post  
Sam
 
Posts: n/a
Default Loudspeaker timing

So you are saying that loudspeaker timing has to do with the audio
signal going to the loudspeakers and not the actual speed of the
sounds coming from the drivers. I made the false assumption that
different frequencies of sound traveled at different speeds. Why are
the signals going to the woofer and tweeter not aligned with one
another? Does the crossover network cause a phase shift in the
signals that pass through them? Speakers and their design really
fascinate me but there is much I need to learn. Do you know of a good
website that explains the whole timing issue?

Sam


  #26   Report Post  
Bob Morein
 
Posts: n/a
Default Loudspeaker timing


"Sam" wrote in message
om...
So you are saying that loudspeaker timing has to do with the audio
signal going to the loudspeakers and not the actual speed of the
sounds coming from the drivers. I made the false assumption that
different frequencies of sound traveled at different speeds. Why are
the signals going to the woofer and tweeter not aligned with one
another? Does the crossover network cause a phase shift in the
signals that pass through them? Speakers and their design really
fascinate me but there is much I need to learn. Do you know of a good
website that explains the whole timing issue?

Sam


I don't know of a website, but here's a brief rundown:

1. The woofer weighs more than the tweeter. Hence it responds slower to the
driving electrical signal. The part of the problem caused by driver delay
can be corrected by sloping the baffle, so as to place the tweeter further
away from the listener than the woofer.

2. A typical crossover makes time alignment impossible. At best, a phase
alignment at the crossover point can be accomplished. Time alignment is
possible only with a "first order crossover", which allows considerable
leakage of low frequency input to the tweeter. This stresses the tweeter,
with a tendency to promote thermal burnout. Tweeters put into systems with
first order crossovers must be specially constructed or used lightly.

3. You may hear the terms "phase alignment" and "time alignment". These are
two different criteria. In principle, time alignment is a tighter, more
difficult design criteria. For continuous wave signals, the result is the
same. For signals which contain non continuous wave components, ie., music,
they are different.

Auditory research suggests that complex noises are not localized by time
delay. However, the ear can distinguish intra-aural time delays as small as
6 microseconds. This suggests that while a time aligned speaker may not help
one better distinguish the position of a violinist, it may help the listener
distinguish the positions of percussive noises or other transients.




  #27   Report Post  
The Devil
 
Posts: n/a
Default Loudspeaker timing

On Mon, 29 Sep 2003 06:45:56 -0400, "Arny Krueger"
wrote:

I often engage in adolescentilism.


That's very honest of you.

--
td
  #28   Report Post  
Arny Krueger
 
Posts: n/a
Default Loudspeaker timing


"The Devil" wrote in message
news:ledhnv4unltuletcnna9t19jmtcd8qhndv@rdmzrnewst xt.nz...

On Mon, 29 Sep 2003 06:45:56 -0400, "Arny Krueger"

never wrote:

I often engage in adolescentilism.


I lie and drink a lot because reality is way to bitter for me.


Thanks for sharing, Graham.




  #29   Report Post  
Arny Krueger
 
Posts: n/a
Default Loudspeaker timing


"Sam" wrote in message
om...

So you are saying that loudspeaker timing has to do with the audio
signal going to the loudspeakers


No, it has to do with the sound coming out of the speakers. The timing of
the sound coming out of a speakers is partially determined by the signal
going into the speakers.

and not the actual speed of the sounds coming from the drivers.


The speed of sound is essentially the same from all of the speakers in the
system.


I made the false assumption that
different frequencies of sound traveled at different speeds.


Yes, you did, and thank you for seeing your error.

Why are
the signals going to the woofer and tweeter not aligned with one
another?


They may or may not be aligned with each other, depending on the crossover
system design.

One effect you haven't mentioned is the fact that the time delay between the
electrical signal going into the speaker, and the acoustic signal (sound)
coming out of the speaker also varies with the speaker type and frequency.

Does the crossover network cause a phase shift in the
signals that pass through them?


Yes.

Speakers and their design really fascinate me but there is much I need to

learn.

Do you know of a good website that explains the whole timing issue?


Introduction:

http://www.libinst.com/tpfd.htm

Very theoretical:

http://www.whise.com.au/time_delay.htm


More practical:

http://www.mlssa.com/mlssa/BROCHUREp2.htm

A book on the topic and others:

http://www.trueaudio.com/ild_rev1.htm




  #30   Report Post  
The Devil
 
Posts: n/a
Default Loudspeaker timing

On Mon, 29 Sep 2003 21:51:34 -0400, "Arny Krueger"
wrote:

I often engage in adolescentilism.


Tha

t
doesn't surprise me at all.


I forgot to mention that I'm a repulsive pervert who should be
strung up by his balls.


I totally agree.

--
td


  #31   Report Post  
Goofball_star_dot_etal
 
Posts: n/a
Default Loudspeaker timing

On Mon, 29 Sep 2003 16:23:45 -0400, "Bob Morein"
wrote:

1. The woofer weighs more than the tweeter. Hence it responds slower to the
driving electrical signal.


One might take some notice if one wanted to throw them. This must be
one of the worst cases of a feral physicist technobabble.

You are loosing(tm) it Bob, IMO.

Ask Dick to clean your clock.

This group is in danger of going to the dogs. . .
  #32   Report Post  
Bob Morein
 
Posts: n/a
Default Loudspeaker timing


"Goofball_star_dot_etal" wrote in message
...
On Mon, 29 Sep 2003 16:23:45 -0400, "Bob Morein"
wrote:

1. The woofer weighs more than the tweeter. Hence it responds slower to

the
driving electrical signal.


One might take some notice if one wanted to throw them. This must be
one of the worst cases of a feral physicist technobabble.

You are loosing(tm) it Bob, IMO.

The wording is an attempt to avoid confusing the reader with moving mass,
resonant frequency, and Q.
Why don't you give it a shot? It could be better.


  #33   Report Post  
Lionel
 
Posts: n/a
Default Loudspeaker timing

Goofball_star_dot_etal wrote:

On Mon, 29 Sep 2003 16:23:45 -0400, "Bob Morein"
wrote:


1. The woofer weighs more than the tweeter. Hence it responds slower to the
driving electrical signal.



One might take some notice if one wanted to throw them. This must be
one of the worst cases of a feral physicist technobabble.

You are loosing(tm) it Bob, IMO.

Ask Dick to clean your clock.

This group is in danger of going to the dogs. . .


Only "in danger" ?

  #34   Report Post  
normanstrong
 
Posts: n/a
Default Loudspeaker timing

My loudspeaker had great timing. It showed up on the market exactly
when I needed a new speaker.

Norm Strong


  #37   Report Post  
George M. Middius
 
Posts: n/a
Default Loudspeaker timing



Goofy said:

The trucks don't have the right weight.


That's what you get for hauling too many willies.


  #38   Report Post  
Goofball_star_dot_etal
 
Posts: n/a
Default Loudspeaker timing

On Tue, 30 Sep 2003 18:47:46 -0400, "Bob Morein"
wrote:


"Goofball_star_dot_etal" wrote in message
...
On Mon, 29 Sep 2003 16:23:45 -0400, "Bob Morein"
wrote:

1. The woofer weighs more than the tweeter. Hence it responds slower to

the
driving electrical signal.


One might take some notice if one wanted to throw them. This must be
one of the worst cases of a feral physicist technobabble.

You are loosing(tm) it Bob, IMO.

The wording is an attempt to avoid confusing the reader with moving mass,
resonant frequency, and Q.
Why don't you give it a shot? It could be better.


It is not just a case of dumbing down the wording for the confused
reader. I fail to see a simple relationship between mass and time
delay. If you were to increase just the mass of the moving parts of
an ideal driver, for a frequency well above resonance, the amplitude
of acceleration, velocity and displacement would all be reduced in
proportion to mass but the phase/time relationship between air
pressure and applied voltage would be the same. If you scale down a
driver in proportion to wavelength, a lot more than just the mass is
changed including the applied force, but again, well above resonance,
the applied force and therefore acceleration, is proportional to the
applied current ( or voltage for constant impedance) and the velocity
and displacement just follow along in proportion, ninety degrees
apart. (assuming a ideal rigid structure). I can see no increased
delay due to increased moving mass of drivers. Scaling can be a tricky
thing, you will note but the motion of "ideal" drivers is not. Maybe
you are thinking of something tricky but it came out dumb - "heavy
equals slow/late"

There is also something dumb here too, we noted. . .

"Auditory research suggests that complex noises are not localized by
time delay. However, the ear can distinguish intra-aural time delays
as small as 6 microseconds. This suggests that while a time aligned
speaker may not help one better distinguish the position of a
violinist, it may help the listener distinguish the positions of
percussive noises or other transients."

How can you change "intra-aural time delays" by any identical change
to two identical speakers?
  #39   Report Post  
Goofball_star_dot_etal
 
Posts: n/a
Default Loudspeaker timing

On Wed, 01 Oct 2003 14:47:20 -0400, George M. Middius
wrote:



Goofy said:

The trucks don't have the right weight.


That's what you get for hauling too many willies.





Just say NO to goofy audio.
  #40   Report Post  
Bob Morein
 
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"Goofball_star_dot_etal" wrote in message
...
On Tue, 30 Sep 2003 18:47:46 -0400, "Bob Morein"
wrote:


"Goofball_star_dot_etal" wrote in message
...
On Mon, 29 Sep 2003 16:23:45 -0400, "Bob Morein"
wrote:

1. The woofer weighs more than the tweeter. Hence it responds slower

to
the
driving electrical signal.

One might take some notice if one wanted to throw them. This must be
one of the worst cases of a feral physicist technobabble.

You are loosing(tm) it Bob, IMO.

The wording is an attempt to avoid confusing the reader with moving mass,
resonant frequency, and Q.
Why don't you give it a shot? It could be better.


It is not just a case of dumbing down the wording for the confused
reader. I fail to see a simple relationship between mass and time
delay. If you were to increase just the mass of the moving parts of
an ideal driver, for a frequency well above resonance, the amplitude
of acceleration, velocity and displacement would all be reduced in
proportion to mass but the phase/time relationship between air
pressure and applied voltage would be the same. If you scale down a
driver in proportion to wavelength, a lot more than just the mass is
changed including the applied force, but again, well above resonance,
the applied force and therefore acceleration, is proportional to the
applied current ( or voltage for constant impedance) and the velocity
and displacement just follow along in proportion, ninety degrees
apart. (assuming a ideal rigid structure). I can see no increased
delay due to increased moving mass of drivers. Scaling can be a tricky
thing, you will note but the motion of "ideal" drivers is not. Maybe
you are thinking of something tricky but it came out dumb - "heavy
equals slow/late"


All correct, above. I was trying to give Sam, who was not aware that the
speed of sound in free space is independent of frequency, something to grab
on to. Doing that, while exhibiting the level of erudition we expect, is
for me an unsolved problem. So I decided to focus on the relationship
between resonant frequency and group delay, and resonant frequency, I
decided, was best represented by one constant in the equation, mass.

If you can think of a way to present more information to Sam, who has just
learned that c is a constant, it would be useful to all of us.
Give it another shot. I'd certainly add it to my repertoire of answers, as
the question will inevitably occur again.


There is also something dumb here too, we noted. . .

"Auditory research suggests that complex noises are not localized by
time delay. However, the ear can distinguish intra-aural time delays
as small as 6 microseconds. This suggests that while a time aligned
speaker may not help one better distinguish the position of a
violinist, it may help the listener distinguish the positions of
percussive noises or other transients."

How can you change "intra-aural time delays" by any identical change
to two identical speakers?


That's a good question. It's intuitively appealing to me that the ear would
better be able to localize an impulse if it actually looks like an impulse,
as opposed to what you and I both know comes out of a non time-aligned
system. And that's all there is. I have no testing, blind or otherwise, to
back it up. I do know I enjoy the hell out of a set of Spicas when they're
set up right.



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