Tom's Hardware > Forum > Audio > Audio Technology > Stereo imaging comes from...where?

Stereo imaging comes from...where?

Forum Audio : Audio Technology - Stereo imaging comes from...where?

Tom's Hardware: Over 1.4 million members in 6 different countries available to answer all your high-tech questions. Sign up now! Its free!
Word :    Username :           
 

Archived from groups: rec.audio.tech (More info?)

 

Hey all;

Well I've been playing with my stereo and a test CD lately. Turns out
that my CD player's outputs are SLIGHTLY different--left channel is a
few percent louder. My preamp, on the other hand, is moderately out of
balance in the opposite direction. One of my amps is substantially off
(an ancient and unrepaired Heathkit), whereas the others are dead on--
after fixing the preamp output levels.

But it's very interesting. I found that matching the output voltage across
the speaker terminals of the amp very carefully made a _substantial_
difference in my ability to place artists and instruments. It got me
wondering if in fact, much of the stereo imaging ability that people
attribute to amps and preamps is in fact tied directly to the balance
between the channels.

Has anyone got some thoughts on this? And am I completely off base here?
For that matter, how unmatched are amplifier channels typically, at the
various levels (mass-market, mid-fi, audiophile, and insane)?

Colin

Sponsored Links
Register or log in to remove.

Archived from groups: rec.audio.tech (More info?)

 

"Colin B." <cbigam@somewhereelse.nucleus.com> wrote in message
news:40bff4df_1@news....
> Hey all;
>
> Well I've been playing with my stereo and a test CD lately. Turns out
> that my CD player's outputs are SLIGHTLY different--left channel is a
> few percent louder. My preamp, on the other hand, is moderately out of
> balance in the opposite direction. One of my amps is substantially off
> (an ancient and unrepaired Heathkit), whereas the others are dead on--
> after fixing the preamp output levels.
>
> But it's very interesting. I found that matching the output voltage across
> the speaker terminals of the amp very carefully made a _substantial_
> difference in my ability to place artists and instruments. It got me
> wondering if in fact, much of the stereo imaging ability that people
> attribute to amps and preamps is in fact tied directly to the balance
> between the channels.
>
> Has anyone got some thoughts on this? And am I completely off base here?
> For that matter, how unmatched are amplifier channels typically, at the
> various levels (mass-market, mid-fi, audiophile, and insane)?
>
> Colin

I have seen many imaging problems I couldn't fix by twiddling the balance
knob.
Conversely, I have heard systems that have enormous sweet spots, extending
well beyond the range where the channels are approximately balanced.
Hence I conclude that channel balance is not an important factor.

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

In article <40bff4df_1@news.>,
"Colin B." <cbigam@somewhereelse.nucleus.com> wrote:

> Hey all;
>
> Well I've been playing with my stereo and a test CD lately. Turns out
> that my CD player's outputs are SLIGHTLY different--left channel is a
> few percent louder. My preamp, on the other hand, is moderately out of
> balance in the opposite direction. One of my amps is substantially off
> (an ancient and unrepaired Heathkit), whereas the others are dead on--
> after fixing the preamp output levels.
>
> But it's very interesting. I found that matching the output voltage across
> the speaker terminals of the amp very carefully made a _substantial_
> difference in my ability to place artists and instruments. It got me
> wondering if in fact, much of the stereo imaging ability that people
> attribute to amps and preamps is in fact tied directly to the balance
> between the channels.
>
> Has anyone got some thoughts on this? And am I completely off base here?
> For that matter, how unmatched are amplifier channels typically, at the
> various levels (mass-market, mid-fi, audiophile, and insane)?
>
> Colin

Amplitude is one factor and phase is the other. They both need to be
reasonably accurate for clear imaging.

Speaker placement is usually the biggest factor. Echoes in the room can
improve or hurt the imaging, depending on how they line up and what kind
of music you're listening to. It something that's best improved through
experimentation.

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Colin,

I agree with Arny that small differences in balance are not significant. The
single most important thing you can do to improve imaging is to avoid first
reflections off the nearby side walls and ceilings. This is usually done by
placing absorber panels in those key spots, though in larger rooms diffusion
can do a similar job.

For more information see the Acoustics FAQ, second in the list on my
Articles page:

www.ethanwiner.com/articles.html

In particular, see the sidebar that describes creating an RFZ (Reflection
Free Zone).

--Ethan

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

In article <40bff4df_1@news.>,
Colin B. <cbigam@somewhereelse.nucleus.com> wrote:
>But it's very interesting. I found that matching the output voltage across
>the speaker terminals of the amp very carefully made a _substantial_
>difference in my ability to place artists and instruments. It got me
>wondering if in fact, much of the stereo imaging ability that people
>attribute to amps and preamps is in fact tied directly to the balance
>between the channels.

Left/right imaging comes from volume and time differences.

Vertical imaging comes at least partly from frequency response (you hear height
from the interaction of the direct sound and floor reflection).

Volume increases/decreases can be perceived as depth changes.

>For that matter, how unmatched are amplifier channels typically, at the
>various levels (mass-market, mid-fi, audiophile, and insane)?

Asymetric rooms also cause substantial (a few dB) frequency dependant level
differences.

--
<a href="http://www.poohsticks.org/drew/">Home Page</a>
Life is a terminal sexually transmitted disease.

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

"Arny Krueger" <arnyk@hotpop.com> wrote in message news:<i-SdnafdQY6t8V3dRVn-tA@comcast.com>...

> by a ca. $1 chip that also does 4-12 other things as well.

Okay, my curiosity is piqued. Any idea of makers, other than the
obvious National Semiconductor? I was just about to design an
all-analog preamp, but something with digital control might be much
simpler and maybe more reliable.

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Georg Grosz wrote:
> "Arny Krueger" <arnyk@hotpop.com> wrote in message
> news:<i-SdnafdQY6t8V3dRVn-tA@comcast.com>...
>
>> by a ca. $1 chip that also does 4-12 other things as well.
>
> Okay, my curiosity is piqued. Any idea of makers, other than the
> obvious National Semiconductor? I was just about to design an
> all-analog preamp, but something with digital control might be much
> simpler and maybe more reliable.

Off the top of my head:

Crystal Semiconductor has a high-quality chip called the CS 3310. Dallas
Semiconductor, Phillips, Toshiba, Sanyo, etc. There are also a number of DAC
chips with built-in volume controls.

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

"Kevin McMurtrie" <mcmurtri@dslextreme.com> wrote in message
news:mcmurtri-EF4853.23504103062004@corp-radius.supernews.com...
> In article <40bff4df_1@news.>,
> "Colin B." <cbigam@somewhereelse.nucleus.com> wrote:
>
> > Hey all;
> >
> > Well I've been playing with my stereo and a test CD lately. Turns out
> > that my CD player's outputs are SLIGHTLY different--left channel is a
> > few percent louder. My preamp, on the other hand, is moderately out of
> > balance in the opposite direction. One of my amps is substantially off
> > (an ancient and unrepaired Heathkit), whereas the others are dead on--
> > after fixing the preamp output levels.
> >
> > But it's very interesting. I found that matching the output voltage
across
> > the speaker terminals of the amp very carefully made a _substantial_
> > difference in my ability to place artists and instruments. It got me
> > wondering if in fact, much of the stereo imaging ability that people
> > attribute to amps and preamps is in fact tied directly to the balance
> > between the channels.
> >
> > Has anyone got some thoughts on this? And am I completely off base here?
> > For that matter, how unmatched are amplifier channels typically, at the
> > various levels (mass-market, mid-fi, audiophile, and insane)?
> >
> > Colin
>
> Amplitude is one factor and phase is the other. They both need to be
> reasonably accurate for clear imaging.
>
> Speaker placement is usually the biggest factor. Echoes in the room can
> improve or hurt the imaging, depending on how they line up and what kind
> of music you're listening to. It something that's best improved through
> experimentation.

Your brain computes sonic positioning primarily in 3 ways:

Temporal differences (different time of arrival between both ears, this is
the main reason for stereo obviously)
Amplitude differences (if something is close it's louder)
Spectral differences (high frequencies decay more in amplitude per unit
distance than low frequencies, so if something is close it's brighter)

There are few other factors but these rely on interpretation from hearing
things before, your "sonic memory" as it were, and this from an other part
of the brain that is way too interpretive and also responsible for the
heated audiophile debates.

So, to be a good imaging speaker, it must do everything right. It's got a
neutral frequency response, doesn't compress, and has a good phase profile
(there are some that say that only a neutral (linear) phase profile will do)
Obviously having the pair matched will have it's temporal advantages.

Wessel

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

"Wessel Dirksen" <wdirksen@p-we.com> wrote in message
news:40d0b190$0$9524$a0ced6e1@news.skynet.be...
>
> "Kevin McMurtrie" <mcmurtri@dslextreme.com> wrote in message
> news:mcmurtri-EF4853.23504103062004@corp-radius.supernews.com...
> > In article <40bff4df_1@news.>,
> > "Colin B." <cbigam@somewhereelse.nucleus.com> wrote:
> >
> > > Hey all;
> > >
> > > Well I've been playing with my stereo and a test CD lately. Turns out
> > > that my CD player's outputs are SLIGHTLY different--left channel is a
> > > few percent louder. My preamp, on the other hand, is moderately out of
> > > balance in the opposite direction. One of my amps is substantially off
> > > (an ancient and unrepaired Heathkit), whereas the others are dead on--
> > > after fixing the preamp output levels.
> > >
> > > But it's very interesting. I found that matching the output voltage
> across
> > > the speaker terminals of the amp very carefully made a _substantial_
> > > difference in my ability to place artists and instruments. It got me
> > > wondering if in fact, much of the stereo imaging ability that people
> > > attribute to amps and preamps is in fact tied directly to the balance
> > > between the channels.
> > >
> > > Has anyone got some thoughts on this? And am I completely off base
here?
> > > For that matter, how unmatched are amplifier channels typically, at
the
> > > various levels (mass-market, mid-fi, audiophile, and insane)?
> > >
> > > Colin
> >
> > Amplitude is one factor and phase is the other. They both need to be
> > reasonably accurate for clear imaging.
> >
> > Speaker placement is usually the biggest factor. Echoes in the room can
> > improve or hurt the imaging, depending on how they line up and what kind
> > of music you're listening to. It something that's best improved through
> > experimentation.
>
> Your brain computes sonic positioning primarily in 3 ways:
>
> Temporal differences (different time of arrival between both ears, this is
> the main reason for stereo obviously)
> Amplitude differences (if something is close it's louder)
> Spectral differences (high frequencies decay more in amplitude per unit
> distance than low frequencies, so if something is close it's brighter)

This is true, but very few stereo recordings make use of this imaging mode.
With multi-track recording techniques, most tracks are mono, and they pan
them to the desired position. Balance controls work the same way. They just
vary the relative loudness of the channels. Binaural recordings and a few
"genuine" stereo recordings preserve phase information. I wish there were
more of these...

> There are few other factors but these rely on interpretation from hearing
> things before, your "sonic memory" as it were, and this from an other part
> of the brain that is way too interpretive and also responsible for the
> heated audiophile debates.
>
> So, to be a good imaging speaker, it must do everything right. It's got a
> neutral frequency response, doesn't compress, and has a good phase profile
> (there are some that say that only a neutral (linear) phase profile will
do)
> Obviously having the pair matched will have it's temporal advantages.
>
> Wessel
>
>

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

"Karl Uppiano" karl_uppiano@verizon.net
wrote:

This is true, but very few stereo recordings make use of this imaging mode.
>With multi-track recording techniques, most tracks are mono, and they pan
>them to the desired position. Balance controls work the same way. They just
>vary the relative loudness of the channels. Binaural recordings and a few
>"genuine" stereo recordings preserve phase information. I wish there were
>more of these...

I went through a binaural 'phase' some time ago and found that every binaural
recording I could find had excellent imaging (localization, placement and
tracking) everywhere EXCEPT in the frontal plane.When the sound source was
supposed to be in front of me I either lost my ability to locate the source or
it appeared to be to my rear.

Late last year at a PSACS meeting Bob Schulein (formerly of Shure Bros and
Etymotic Reseacch) demonstrated a project using Etymotic Research microphones
(hearing aid) and a portable DAT where we could make binaural recordings using
our own ears.

Somewhat surprisingly I found the same problems. Recording normal activity in a
room I found that when I played back the recording on headphones that I still
had front-back reversal for sounds that should have been located in the frontal
plane.

This also remained true for video/audio recordings that Bob had made using his
ears but occasionally would be more bizarre. When he would describe the scene
(walking along the beach, for example) when he would describe the surf as being
on the right it would appear to be behind me.

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

On Thu, 17 Jun 2004 03:33:05 GMT, "Karl Uppiano"
<karl_uppiano@verizon.net> wrote:

>This is true, but very few stereo recordings make use of this imaging mode.
>With multi-track recording techniques, most tracks are mono, and they pan
>them to the desired position. Balance controls work the same way. They just
>vary the relative loudness of the channels. Binaural recordings and a few
>"genuine" stereo recordings preserve phase information. I wish there were
>more of these...

It could be said that ALL stereo recordings do. It's just that most
recordings are dual-channel pan-potted mono.

I'm surprised at the general indifference to real stereo. When
instruments are positioned in stereo space they retain their identity,
don't have to be destructively eq'd in order to make "room" in the
mix...

I'm sure the illusion of stereo could be synthesised even for
individually recorded tracks. But the commercial music industry seem
to have completely missed this area.

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Laurence Payne wrote:
> On Thu, 17 Jun 2004 03:33:05 GMT, "Karl Uppiano"
> <karl_uppiano@verizon.net> wrote:
>
>
>>This is true, but very few stereo recordings make use of this imaging mode.
>>With multi-track recording techniques, most tracks are mono, and they pan
>>them to the desired position. Balance controls work the same way. They just
>>vary the relative loudness of the channels. Binaural recordings and a few
>>"genuine" stereo recordings preserve phase information. I wish there were
>>more of these...
>
>
> It could be said that ALL stereo recordings do. It's just that most
> recordings are dual-channel pan-potted mono.
>
> I'm surprised at the general indifference to real stereo. When
> instruments are positioned in stereo space they retain their identity,
> don't have to be destructively eq'd in order to make "room" in the
> mix...
>
> I'm sure the illusion of stereo could be synthesised even for
> individually recorded tracks. But the commercial music industry seem
> to have completely missed this area.
On the subject of imaging, I've found that Densen's DeMagic CD is
wonderful for setting your stereo back to neutral and getting its
imaging back. Before I purchased it, I noticed that my speaker's imaging
had gotten quite vague, and it was especially bnoticeable when playing
mono. As a test, before DeMagic, I put my speakers less than 1 foot
apart and played a signal in mono. As suspected, the central image was
weak. With the speakers being so close together the image should have
been practically set in stone. I ran the Demagic CD and imaging was
restored. Now I play that CD once a week, especially before sitting down
to some good music or watching a DVD.

No, I don't sell Demagic, I'm just have great raves for it and want to
share the love:) If you do get the CD, remember to play it as loud as is
comfortable. You probably should leave the room and close the doors
while it plays for 4 minutes. It isn't pleasant. Apparently the sound
that it plays de-magnetizes the audio circuits it goes through,
especially the speaker voicecoils and crossovers.

CD

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Codifus <codifus@optonline.net> wrote:

> On the subject of imaging, I've found that Densen's DeMagic CD is
> wonderful for setting your stereo back to neutral and getting its
> imaging back.

(snip!)

> Apparently the sound
> that it plays de-magnetizes the audio circuits it goes through,
> especially the speaker voicecoils and crossovers.

Cool! Does it demagnetise the air in the room as well? Or pair up free
ions?

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

On Mon, 21 Jun 2004 16:39:24 -0400, Codifus <codifus@optonline.net>
wrote:

>On the subject of imaging, I've found that Densen's DeMagic CD is
>wonderful for setting your stereo back to neutral and getting its
>imaging back. Before I purchased it, I noticed that my speaker's imaging
>had gotten quite vague, and it was especially bnoticeable when playing
>mono. As a test, before DeMagic, I put my speakers less than 1 foot
>apart and played a signal in mono. As suspected, the central image was
>weak. With the speakers being so close together the image should have
>been practically set in stone. I ran the Demagic CD and imaging was
>restored. Now I play that CD once a week, especially before sitting down
>to some good music or watching a DVD.
>
>No, I don't sell Demagic, I'm just have great raves for it and want to
>share the love:) If you do get the CD, remember to play it as loud as is
>comfortable. You probably should leave the room and close the doors
>while it plays for 4 minutes. It isn't pleasant. Apparently the sound
>that it plays de-magnetizes the audio circuits it goes through,
>especially the speaker voicecoils and crossovers.

Definitely magic! 'Cos it sure ain't anything else :-)

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Codifus <codifus@optonline.net> wrote in message news:<cb7gnj$15hd$1@news.interpublic.com>...
> On the subject of imaging, I've found that Densen's DeMagic CD is
> wonderful for setting your stereo back to neutral and getting its
> imaging back. Before I purchased it, I noticed that my speaker's imaging
> had gotten quite vague, and it was especially bnoticeable when playing
> mono. As a test, before DeMagic, I put my speakers less than 1 foot
> apart and played a signal in mono. As suspected, the central image was
> weak. With the speakers being so close together the image should have
> been practically set in stone. I ran the Demagic CD and imaging was
> restored. Now I play that CD once a week, especially before sitting down
> to some good music or watching a DVD.
>
> No, I don't sell Demagic, I'm just have great raves for it and want to
> share the love:) If you do get the CD, remember to play it as loud as is
> comfortable. You probably should leave the room and close the doors
> while it plays for 4 minutes. It isn't pleasant. Apparently the sound
> that it plays de-magnetizes the audio circuits it goes through,
> especially the speaker voicecoils and crossovers.

Codifus, could you please explain to us how a voice coil, made
of copper, aluminum, paper, plastic and adhesive, NON of which
are magnetic materials, can be demagnitized by this marvelous
contrivance. For that matter, can you explain how these non-
magnetic subtances get magnetized in the first place such that
they might require demagnetizing?

Could you also explain how the audio circuits, consisting of more
copper, silicon, fiberglass resins and other plastics, and all
these other NONmagnetic materials are demagnitized by this wonderful
device. And, for that matter, could you please explain how such NON
magnetic materials got magnetized in the first place?

Let's simplify the question somewhat:

How does a NONmagnetic object, like a voice coil, get
magnetized?

What benefit is there to demagnetize an object that can't
be magnetized to begin with?

The answers to these question, I am most certain, will reveal
truly what magic is. Let's see, from Webster's we read:

ma gic 1 a: the use of means (as charms or spells)
believed to have supernatural power over natural
forces, b: magic rites or incantations, 2 a: an
extraordinary power or influence seemingly from
a supernatural source, b: something which seems
to cast a spell, 3: the art of producing illusions
by sleight of hand

Please help us out here, if you would kindly do so, when a Densen
DeMagic CD demagnetizes objects that can't be magnetized to
begin with, what kind of magic it use:

1. Charms?
2. Rites and incantations
3. Supernatural sources?
4. Casting of spells
5. Illusion by sleight of hand?

To those who have the instrumentation and know how, and I humbly
include myself among them having designed and measured voice
coils and audio circuits of many persuasions, to measure static
and dynmaically varying magnetizations of objects with great
sensitivity, how would I know when a non-magnetizable object is
magnetized? How would I know when a magnetized non-magnetizable
becomes demagnetized? Basically, what's the difference between:

1. An unmagnetized nonmagnetizable object
2. A magnetized nonmagnetizable object
3. A demagnetized nonmagnetizable object

Or is, it, uhm, "magic?"

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

dpierce@cartchunk.org (Dick Pierce) wrote:

>Codifus <codifus@optonline.net> wrote in message news:<cb7gnj$15hd$1@news.interpublic.com>...
>> On the subject of imaging, I've found that Densen's DeMagic CD is
>> wonderful for setting your stereo back to neutral and getting its
>> imaging back. Before I purchased it, I noticed that my speaker's imaging
>> had gotten quite vague, and it was especially bnoticeable when playing
>> mono. As a test, before DeMagic, I put my speakers less than 1 foot
>> apart and played a signal in mono. As suspected, the central image was
>> weak. With the speakers being so close together the image should have
>> been practically set in stone. I ran the Demagic CD and imaging was
>> restored. Now I play that CD once a week, especially before sitting down
>> to some good music or watching a DVD.
>>
>> No, I don't sell Demagic, I'm just have great raves for it and want to
>> share the love:) If you do get the CD, remember to play it as loud as is
>> comfortable. You probably should leave the room and close the doors
>> while it plays for 4 minutes. It isn't pleasant. Apparently the sound
>> that it plays de-magnetizes the audio circuits it goes through,
>> especially the speaker voicecoils and crossovers.
>
>Codifus, could you please explain to us how a voice coil, made
>of copper, aluminum, paper, plastic and adhesive, NON of which
>are magnetic materials, can be demagnitized by this marvelous
>contrivance. For that matter, can you explain how these non-
>magnetic subtances get magnetized in the first place such that
>they might require demagnetizing?
>
>Could you also explain how the audio circuits, consisting of more
>copper, silicon, fiberglass resins and other plastics, and all
>these other NONmagnetic materials are demagnitized by this wonderful
>device. And, for that matter, could you please explain how such NON
>magnetic materials got magnetized in the first place?
>
>Let's simplify the question somewhat:
>
> How does a NONmagnetic object, like a voice coil, get
> magnetized?
>
> What benefit is there to demagnetize an object that can't
> be magnetized to begin with?
>
>The answers to these question, I am most certain, will reveal
>truly what magic is. Let's see, from Webster's we read:
>
> ma gic 1 a: the use of means (as charms or spells)
> believed to have supernatural power over natural
> forces, b: magic rites or incantations, 2 a: an
> extraordinary power or influence seemingly from
> a supernatural source, b: something which seems
> to cast a spell, 3: the art of producing illusions
> by sleight of hand
>
>Please help us out here, if you would kindly do so, when a Densen
>DeMagic CD demagnetizes objects that can't be magnetized to
>begin with, what kind of magic it use:
>
> 1. Charms?
> 2. Rites and incantations
> 3. Supernatural sources?
> 4. Casting of spells
> 5. Illusion by sleight of hand?
>
>To those who have the instrumentation and know how, and I humbly
>include myself among them having designed and measured voice
>coils and audio circuits of many persuasions, to measure static
>and dynmaically varying magnetizations of objects with great
>sensitivity, how would I know when a non-magnetizable object is
>magnetized? How would I know when a magnetized non-magnetizable
>becomes demagnetized? Basically, what's the difference between:
>
> 1. An unmagnetized nonmagnetizable object
> 2. A magnetized nonmagnetizable object
> 3. A demagnetized nonmagnetizable object
>
>Or is, it, uhm, "magic?"

Ahh Dick, ye of little faith.

So, you need proof and a scientific explanation? This comes directly from one of
the sites selling this product, so it must be true:

"How does the Densen DeMagic work? All electronic parts (resistors, capacitors
etc) contain a small amount of magnets. Due to the DC leakage from all
electronic equipment, these magnets will gradually be orientated in one
direction. Over time, this affects the signal transfer through the whole system
and lowers the quality of the reproduced sound. DeMagic sends a series of
complex algorithm signals through your system, which relocates the magnets and
thereby breaks the magnetic field and its negative effects on sound."

Now we all know that algorithms are superior to heuristics, and the Densen
DeMagic CD goes even further by using really "complex" algorithms, as opposed to
just "simple" algorithms.

So, for only $20, it seems to be right up there with green marking pens, as a
device for making a very real, very obvious, and a very significant
improvement...








....to any company's bottom line profits.

Harvey Gerst
Indian Trail Recording Studio
http://www.ITRstudio.com/

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

"Wessel Dirksen" <wdirksen@p-we.com> wrote in message news:<40d0b190$0$9524
> Your brain computes sonic positioning primarily in 3 ways:
>
> Temporal differences (different time of arrival between both ears, this is
> the main reason for stereo obviously)
> Amplitude differences (if something is close it's louder)
> Spectral differences (high frequencies decay more in amplitude per unit
> distance than low frequencies, so if something is close it's brighter)
>
> There are few other factors but these rely on interpretation from hearing
> things before, your "sonic memory" as it were, and this from an other part
> of the brain that is way too interpretive and also responsible for the
> heated audiophile debates.
>
> So, to be a good imaging speaker, it must do everything right. It's got a
> neutral frequency response, doesn't compress, and has a good phase profile
> (there are some that say that only a neutral (linear) phase profile will do)
> Obviously having the pair matched will have it's temporal advantages.
>
> Wessel
_____________
Good show Wess-

And to the point on the temporal issue, I'd dare anyone on this thread
to believe that their ears are prefectly parrallel to each other.
That is, one ear is not slightly to the rear of the other, as measured
through the skull.
IE if your left ear is even 0.5MM! forward of your right, the left
channel of just about anything you listen to, except headphones, will
*seem* louder, 'cause the sound is reaching it first. And vice versa
for the right.

Not to mention that one ear canal may also be deeper than the other,
or that the angle down the canals may vary slightly, and on and on but
I'm wearing my fingers ount typign her so, hopin' yor news is good
wews, GOONIGHT!

-CC

Reply to Anonymous
- 0 +

Archived from groups: rec.audio.tech (More info?)

 

In article <77a787ce.0406241712.28a69b36@posting.google.com>,
ckozicki@snet.net (ChrisCoaster) wrote:


> And to the point on the temporal issue, I'd dare anyone on this thread
> to believe that their ears are prefectly parrallel to each other.
> That is, one ear is not slightly to the rear of the other, as measured
> through the skull.
> IE if your left ear is even 0.5MM! forward of your right, the left
> channel of just about anything you listen to, except headphones, will
> *seem* louder, 'cause the sound is reaching it first. And vice versa
> for the right.
>
> Not to mention that one ear canal may also be deeper than the other,
> or that the angle down the canals may vary slightly, and on and on but
> I'm wearing my fingers ount typign her so, hopin' yor news is good
> wews, GOONIGHT!
>
> -CC

It's funny that so many people are worried about buying expensive audio
gear when the weakest link in the chain is attached to the sides of
every human's head.

--
cyrus

*coughcasaucedoprodigynetcough*

Reply to Cyrus

Archived from groups: rec.audio.tech (More info?)

 

"ChrisCoaster" <ckozicki@snet.net> wrote in message
news:77a787ce.0406241712.28a69b36@posting.google.com...
> "Wessel Dirksen" <wdirksen@p-we.com> wrote in message
news:<40d0b190$0$9524
> > Your brain computes sonic positioning primarily in 3 ways:
> >
> > Temporal differences (different time of arrival between both ears, this
is
> > the main reason for stereo obviously)
> > Amplitude differences (if something is close it's louder)
> > Spectral differences (high frequencies decay more in amplitude per unit
> > distance than low frequencies, so if something is close it's brighter)
> >
> > There are few other factors but these rely on interpretation from
hearing
> > things before, your "sonic memory" as it were, and this from an other
part
> > of the brain that is way too interpretive and also responsible for the
> > heated audiophile debates.
> >
> > So, to be a good imaging speaker, it must do everything right. It's got
a
> > neutral frequency response, doesn't compress, and has a good phase
profile
> > (there are some that say that only a neutral (linear) phase profile will
do)
> > Obviously having the pair matched will have it's temporal advantages.
> >
> > Wessel
> _____________
> Good show Wess-
>
> And to the point on the temporal issue, I'd dare anyone on this thread
> to believe that their ears are prefectly parrallel to each other.
> That is, one ear is not slightly to the rear of the other, as measured
> through the skull.
> IE if your left ear is even 0.5MM! forward of your right, the left
> channel of just about anything you listen to, except headphones, will
> *seem* louder, 'cause the sound is reaching it first. And vice versa
> for the right.
>
> Not to mention that one ear canal may also be deeper than the other,
> or that the angle down the canals may vary slightly, and on and on but
> I'm wearing my fingers ount typign her so, hopin' yor news is good
> wews, GOONIGHT!

Yeah, wondering why the "demagnitized, vibration absorbed, non-diffractive,
non-inductive, calibrated head vice" hasn't been marketed yet. Then we would
really hear something interesting about phase relationships from Dick
Pierce.

But although relevant as you state, it doesn't appear to be quite that
sensitive but I don't think anybody knows for sure how much for hi-fi.
Directionality (vertical axis) is obviously quite sensitive because of
diffractive properties of the head. If you rotate your head too much, it
gets literally in the way of the ear in back. In the horizontal axis, once
"facing the sound" where the angle of plane of the ear axis is +/- few
degrees of the incident sound wave, you probably have a few centimeters of
leeway for important frequencies for imaging.

If I remember correctly, a part of the head related fransfer function (this
was addressed just recently in the Cables thread), the shape of the outer
ear "shell" does help to correct this to some degree with a "fresnel lens"
type of property focused at voice intelligability related frequencies (400
to 800 Hz). Also the sensitivity of phase differences is frequency dependant
according to the wavelength which gets smaller with increasing frequencies.
A 5cm change in signal path length represents only a 5 degree shift in phase
at 100 Hz, but at 1000 Hz, 5cm represents +/- 540 deg (a complete 360 deg
jump + 180 deg out of phase)

Interesting is that the characteristics of our ears indicates that they were
naturally selected for communication with each other and not for being the
ultimate wilderness survival tool like some other animals. Can you imagine
how good your stereo would sound if you were a dog?

Good Fun. Wessel

> -CC

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

cyrus <invalid@i.like.spam> wrote in message news:<invalid-C6B859.19583024062004@newsclstr01.news.prodigy.com>...

> >
> > Not to mention that one ear canal may also be deeper than the other,
> > or that the angle down the canals may vary slightly, and on and on but
> > I'm wearing my fingers ount typign her so, hopin' yor news is good
> > wews, GOONIGHT!
> >
> > -CC
>
> It's funny that so many people are worried about buying expensive audio
> gear when the weakest link in the chain is attached to the sides of
> every human's head.
________________________
Not unless of course you have an aunt like one of mine; as my uncle
will testify, she can hear the lawn grow!

LOL

-CC

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Dick Pierce wrote:
> Codifus <codifus@optonline.net> wrote in message news:<cb7gnj$15hd$1@news.interpublic.com>...
>
>>On the subject of imaging, I've found that Densen's DeMagic CD is
>>wonderful for setting your stereo back to neutral and getting its
>>imaging back. Before I purchased it, I noticed that my speaker's imaging
>>had gotten quite vague, and it was especially bnoticeable when playing
>>mono. As a test, before DeMagic, I put my speakers less than 1 foot
>>apart and played a signal in mono. As suspected, the central image was
>>weak. With the speakers being so close together the image should have
>>been practically set in stone. I ran the Demagic CD and imaging was
>>restored. Now I play that CD once a week, especially before sitting down
>>to some good music or watching a DVD.
>>
>>No, I don't sell Demagic, I'm just have great raves for it and want to
>>share the love:) If you do get the CD, remember to play it as loud as is
>>comfortable. You probably should leave the room and close the doors
>>while it plays for 4 minutes. It isn't pleasant. Apparently the sound
>>that it plays de-magnetizes the audio circuits it goes through,
>>especially the speaker voicecoils and crossovers.
>
>
> Codifus, could you please explain to us how a voice coil, made
> of copper, aluminum, paper, plastic and adhesive, NON of which
> are magnetic materials, can be demagnitized by this marvelous
> contrivance. For that matter, can you explain how these non-
> magnetic subtances get magnetized in the first place such that
> they might require demagnetizing?
>
> Could you also explain how the audio circuits, consisting of more
> copper, silicon, fiberglass resins and other plastics, and all
> these other NONmagnetic materials are demagnitized by this wonderful
> device. And, for that matter, could you please explain how such NON
> magnetic materials got magnetized in the first place?
>
> Let's simplify the question somewhat:
>
> How does a NONmagnetic object, like a voice coil, get
> magnetized?
>
> What benefit is there to demagnetize an object that can't
> be magnetized to begin with?
>
> The answers to these question, I am most certain, will reveal
> truly what magic is. Let's see, from Webster's we read:
>
> ma gic 1 a: the use of means (as charms or spells)
> believed to have supernatural power over natural
> forces, b: magic rites or incantations, 2 a: an
> extraordinary power or influence seemingly from
> a supernatural source, b: something which seems
> to cast a spell, 3: the art of producing illusions
> by sleight of hand
>
> Please help us out here, if you would kindly do so, when a Densen
> DeMagic CD demagnetizes objects that can't be magnetized to
> begin with, what kind of magic it use:
>
> 1. Charms?
> 2. Rites and incantations
> 3. Supernatural sources?
> 4. Casting of spells
> 5. Illusion by sleight of hand?
>
> To those who have the instrumentation and know how, and I humbly
> include myself among them having designed and measured voice
> coils and audio circuits of many persuasions, to measure static
> and dynmaically varying magnetizations of objects with great
> sensitivity, how would I know when a non-magnetizable object is
> magnetized? How would I know when a magnetized non-magnetizable
> becomes demagnetized? Basically, what's the difference between:
>
> 1. An unmagnetized nonmagnetizable object
> 2. A magnetized nonmagnetizable object
> 3. A demagnetized nonmagnetizable object
>
> Or is, it, uhm, "magic?"
I just hear it, so it's not really magic. Whatever the
electrical/magnetic explanation may be, I heard from my speakers a much
better defined image, especially with the mono test. Also, with my basic
understanding of electronics, anything that can carry an electrical
charge will also have an associated magnetic field. If I remember
correctly, the associated magnetic field is always at right angles to
the electrical field. That's a basic law of Physics.

When I ran DeMagic for the 1st time it was very very noticeable on my
system. So after 3 years of use, the circuits in my system must have
become all out of whack magnetically. The other times, The effect is
much more subltle, if it's there at all, but since I know it worked the
first time, it must be doing a little something each time I use it. it's
only $20 and you buy it once, so how much snake oil can it really be?

For those of you with systems that have been in use a couple of years or
so, I dare you to try it. Do the mono test I described earlier first
before running Demagic. You will hear the difference in imaging.

When I ran it in my car stereo, the most noticeable change was that bass
became much much better defined, less loose and vague. I didn't notice
imaging so much, but then my car stereo does not have the ideal
positioning for imaging with the front main speakers by my ankles:)

CD

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

On Fri, 25 Jun 2004 13:29:55 -0400, Codifus <codifus@optonline.net>
wrote:

>> Or is, it, uhm, "magic?"
>I just hear it, so it's not really magic. Whatever the
>electrical/magnetic explanation may be, I heard from my speakers a much
>better defined image, especially with the mono test. Also, with my basic
>understanding of electronics, anything that can carry an electrical
>charge will also have an associated magnetic field. If I remember
>correctly, the associated magnetic field is always at right angles to
>the electrical field. That's a basic law of Physics.
>
>When I ran DeMagic for the 1st time it was very very noticeable on my
>system. So after 3 years of use, the circuits in my system must have
>become all out of whack magnetically. The other times, The effect is
>much more subltle, if it's there at all, but since I know it worked the
>first time, it must be doing a little something each time I use it. it's
>only $20 and you buy it once, so how much snake oil can it really be?
>
>For those of you with systems that have been in use a couple of years or
>so, I dare you to try it. Do the mono test I described earlier first
>before running Demagic. You will hear the difference in imaging.
>
>When I ran it in my car stereo, the most noticeable change was that bass
>became much much better defined, less loose and vague. I didn't notice
>imaging so much, but then my car stereo does not have the ideal
>positioning for imaging with the front main speakers by my ankles:)

We all know the given explanation is bullshit. So, given that it
DOES make a difference, you might find it interesting to try and
discover how.

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Codifus <codifus@optonline.net> wrote:

OK, you're going to get a LOT of flak on this one. Let me point out a
few obvious points.

> I just hear it, so it's not really magic. Whatever the
> electrical/magnetic explanation may be, I heard from my speakers a much
> better defined image, especially with the mono test. Also, with my basic
> understanding of electronics, anything that can carry an electrical
> charge will also have an associated magnetic field. If I remember
> correctly, the associated magnetic field is always at right angles to
> the electrical field. That's a basic law of Physics.

Please don't argue with physics if you don't understand the subject.

1) How do you quantify image definition?
2) How do you do controlled tests on this system?
3) What does the instantaneous magnetic field have to do with long-term
magnetisation?

Basically, you're using your partial opinions in an uncontrolled listening
scenario to claim a change in an undefined value, and then retroactively
applying bad science to justify it.

Is there a difference in what you hear? Absolutely--you heard a difference,
your perception of the sound is different!
Is there a difference in the sound itself? If it can't be measured and can't
be reproduced in a controlled setting, then no.

In other words, all of the differences, while very real, have occurred
between your eardrum and your brain.

> much more subltle, if it's there at all, but since I know it worked the
> first time, it must be doing a little something each time I use it. it's
> only $20 and you buy it once, so how much snake oil can it really be?

Well, it can't be any more than 100% snake oil. Although if you treat it
with my green marker, I can increase the concentration above 100%.

> For those of you with systems that have been in use a couple of years or
> so, I dare you to try it. Do the mono test I described earlier first
> before running Demagic. You will hear the difference in imaging.

I'd love to do so, in a controlled environment. "Imaging" is an unmeasurable
term though, as it stands, so the only way to determine if it works is in a
double-blind test. Not that easy to do when the 'treatment' affects an
entire system.

Colin

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Laurence Payne wrote:

> On Fri, 25 Jun 2004 13:29:55 -0400, Codifus <codifus@optonline.net>
> wrote:
>
>
>>>Or is, it, uhm, "magic?"
>>
>>I just hear it, so it's not really magic. Whatever the
>>electrical/magnetic explanation may be, I heard from my speakers a much
>>better defined image, especially with the mono test. Also, with my basic
>>understanding of electronics, anything that can carry an electrical
>>charge will also have an associated magnetic field. If I remember
>>correctly, the associated magnetic field is always at right angles to
>>the electrical field. That's a basic law of Physics.
>>
>>When I ran DeMagic for the 1st time it was very very noticeable on my
>>system. So after 3 years of use, the circuits in my system must have
>>become all out of whack magnetically. The other times, The effect is
>>much more subltle, if it's there at all, but since I know it worked the
>>first time, it must be doing a little something each time I use it. it's
>>only $20 and you buy it once, so how much snake oil can it really be?
>>
>>For those of you with systems that have been in use a couple of years or
>>so, I dare you to try it. Do the mono test I described earlier first
>>before running Demagic. You will hear the difference in imaging.
>>
>>When I ran it in my car stereo, the most noticeable change was that bass
>>became much much better defined, less loose and vague. I didn't notice
>>imaging so much, but then my car stereo does not have the ideal
>>positioning for imaging with the front main speakers by my ankles:)
>
>
> We all know the given explanation is bullshit. So, given that it
> DOES make a difference, you might find it interesting to try and
> discover how.
To me, their explanation is plausible. Whether it's actually true or not
I don't really know. But I know what ears were telling me: it works.

CD

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Colin B. wrote:
> Codifus <codifus@optonline.net> wrote:
>
> OK, you're going to get a LOT of flak on this one. Let me point out a
> few obvious points.
Flak from you.

>
>
>>I just hear it, so it's not really magic. Whatever the
>>electrical/magnetic explanation may be, I heard from my speakers a much
>>better defined image, especially with the mono test. Also, with my basic
>>understanding of electronics, anything that can carry an electrical
>>charge will also have an associated magnetic field. If I remember
>>correctly, the associated magnetic field is always at right angles to
>>the electrical field. That's a basic law of Physics.
>
>
> Please don't argue with physics if you don't understand the subject.
I'm not arguing with physics. I was stating why Densen's reasoning was
beleivable in my view. Besides, I wasn't wrong about the relationship
between electricity and magnetism, was I? Your clever reply tries to
suggest I'm wrong, yet one of the prvious posters said, and did not
imply, that magnetism wasn't involved in this issue, and that's
completely wrong. Anywhere there's electricity, there's magnetism. You
don't need to be Einstein to understand that basic law.
>
> 1) How do you quantify image definition?
> 2) How do you do controlled tests on this system?
> 3) What does the instantaneous magnetic field have to do with long-term
> magnetisation?
>
> Basically, you're using your partial opinions in an uncontrolled listening
> scenario to claim a change in an undefined value, and then retroactively
> applying bad science to justify it.
>
> Is there a difference in what you hear? Absolutely--you heard a difference,
> your perception of the sound is different!
> Is there a difference in the sound itself? If it can't be measured and can't
> be reproduced in a controlled setting, then no.
>
> In other words, all of the differences, while very real, have occurred
> between your eardrum and your brain.
No, the differences aren't in my head. Like I said earlier, the
difference was very apparent the 1st time I used it. After that, what it
was doing was probably much harder to detect, simply because I did not
let my system stay so long without running it. And yes, imaging is very
very subjective. I've known lots of people who claim they're into
stereos, and from 2 seconds of me walking by their system to instantly
hear that their speakers are wired out of phase, that tells me otherwise.

>
>
>>much more subltle, if it's there at all, but since I know it worked the
>>first time, it must be doing a little something each time I use it. it's
>>only $20 and you buy it once, so how much snake oil can it really be?
>
>
> Well, it can't be any more than 100% snake oil. Although if you treat it
> with my green marker, I can increase the concentration above 100%.
Go ahead and be a cynic if it works for you.

>
>
>>For those of you with systems that have been in use a couple of years or
>>so, I dare you to try it. Do the mono test I described earlier first
>>before running Demagic. You will hear the difference in imaging.
>
>
> I'd love to do so, in a controlled environment. "Imaging" is an unmeasurable
> term though, as it stands, so the only way to determine if it works is in a
> double-blind test. Not that easy to do when the 'treatment' affects an
> entire system.
In a controlled environment, I'm sure the results would be even more
apparent, but you don't need to go that far.
>
> Colin

CD

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

On Sat, 26 Jun 2004 20:27:14 GMT, Codifus <codifus@optonline.net>
wrote:

>> In other words, all of the differences, while very real, have occurred
>> between your eardrum and your brain.


>No, the differences aren't in my head. Like I said earlier, the
>difference was very apparent the 1st time I used it. After that, what it
>was doing was probably much harder to detect, simply because I did not
>let my system stay so long without running it. And yes, imaging is very
>very subjective. I've known lots of people who claim they're into
>stereos, and from 2 seconds of me walking by their system to instantly
>hear that their speakers are wired out of phase, that tells me otherwise.


OK. Given that the differences are real, let's try to discover what
causes them. The magnetic thing is mumbo-jumbo.

This is a really LOUD unpleasant noise that is played? Do you hear
it?

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

Codifus wrote:

> is very very subjective. I've known lots of people who claim they're
> into stereos, and from 2 seconds of me walking by their system to
> instantly hear that their speakers are wired out of phase, that tells
> me otherwise.

That's odd, because it's pretty obvious to most here that yours certainly
were at one point.

geoff

Reply to Anonymous

Archived from groups: rec.audio.tech (More info?)

 

cyrus wrote:

> It's funny that so many people are worried about buying expensive
> audio gear when the weakest link in the chain is attached to the
> sides of every human's head.
]

WRONG ! There is in many cases a far weaker link between those organs.

geoff

Reply to Anonymous
- 0 +

Archived from groups: rec.audio.tech (More info?)

 

In article <aEGDc.5075$NA1.472197@news02.tsnz.net>,
"Geoff Wood" <geoff@paf.co.nz-nospam> wrote:

> cyrus wrote:
>
> > It's funny that so many people are worried about buying expensive
> > audio gear when the weakest link in the chain is attached to the
> > sides of every human's head.
> ]
>
> WRONG ! There is in many cases a far weaker link between those organs.
>
> geoff
>
>

hehe Or the grey matter, I agree.

--
cyrus

*coughcasaucedoprodigynetcough*

Reply to Cyrus

Archived from groups: rec.audio.tech (More info?)

 

Codifus <codifus@optonline.net> wrote:
> Colin B. wrote:
>> Codifus <codifus@optonline.net> wrote:
>>
>> OK, you're going to get a LOT of flak on this one. Let me point out a
>> few obvious points.
> Flak from you.

>> Please don't argue with physics if you don't understand the subject.

> I'm not arguing with physics. I was stating why Densen's reasoning was
> beleivable in my view.

That is because you're understanding of physics is wrong. Just because
electricity and magnetism are interrelated doesn't magically create some
way of building up a static magnetic field in nonmagnetic materials,
which is EXACTLY what would have to happen for this thing to work as
you understand it.

> Besides, I wasn't wrong about the relationship
> between electricity and magnetism, was I?

You weren't wrong in claiming that it exists. You're wrong in your
understanding of it.

> that magnetism wasn't involved in this issue, and that's
> completely wrong. Anywhere there's electricity, there's magnetism. You
> don't need to be Einstein to understand that basic law.

Unfortunately, you don't understand this "law" at all, certainly not why
it's irrelevant.

>> In other words, all of the differences, while very real, have occurred
>> between your eardrum and your brain.

> No, the differences aren't in my head. Like I said earlier, the
> difference was very apparent the 1st time I used it. After that, what it
> was doing was probably much harder to detect, simply because I did not
> let my system stay so long without running it. And yes, imaging is very
> very subjective. I've known lots of people who claim they're into
> stereos, and from 2 seconds of me walking by their system to instantly
> hear that their speakers are wired out of phase, that tells me otherwise.

Heh. Anyone who CAN'T tell that their speakers are out of phase is in
trouble, audibly speaking. Amazingly, it's also trivial to (a) measure
the phase and (b)explain why it makes a difference.

> Go ahead and be a cynic if it works for you.

In the absence of facts or plausible explanation, I will, thank you.

> In a controlled environment, I'm sure the results would be even more
> apparent, but you don't need to go that far.

We disagree on this one, but it would be an interesting experiment. I'd
be willing to wager a decent power amplifier that the differences would
disappear in a controlled environment.

Reply to Anonymous
Tom's Hardware > Forum > Audio > Audio Technology > Stereo imaging comes from...where?
Go to:

There are 1156 identified and unidentified users. To see the list of identified users, Click here.

Please mind

You are about to answer a thread that has been inactive for more than 6 months.
If you still wish to proceed, please ensure that your posting is original and does not duplicate or overlap any prior responses to this thread.

Add a reply Cancel
Sponsored links
  • Ask the community now
  • Publish
Ad
They won a badge
Join us in greeting them
  • 01:00 vianescute won the Freshman badge
  • 01:00 meywd won the Freshman badge
  • 01:00 nayega won the Freshman badge
  • 01:00 gpfear won the Freshman badge
  • 01:00 Conrad925 won the Freshman badge
  • 01:00 skythra won the Freshman badge
  • 01:00 Ckaz won the Freshman badge
  • 01:00 james59 won the Uniformed badge
  • 01:00 snarl won the Uniformed badge
  • 01:00 patlabor44 won the Uniformed badge