Eiron wrote:

Brian wrote:


If you look at the sampling rate of SACD's, there is no doubt that a
frequency response greater than 20khz is possible. And amplifiers don't
cut off at 20khz, so that is not a problem either. Now, your ears, on
the other hand..


My Amplifier is rated at 20Hz to 20KHz.
Sony now sell Amplifiers that are build for a frequency response of
well beyond 20K. Sony call these group of items Extended Range.
www.sony.co.nz
There's always something new in Technology.

My old Rotel claims a frequency response of 4-100,000Hz at +0.5dB, -3dB.

So what's new in your technology, Brian?

Speakers that can extend up to 70Khz must be new. Most common specs
I've seen for speakers are 20Hz to 20Khz

I'm just quoting the specs for my amplifer which is 20Hz to 20KHz

Regards Brian

"Ozzy 2005" wrote in message
...
It is simply incredible how any time BOSE is mentioned the threads are
infinitely long. AMAZING what some good propaganda can do to the crowd.
Long live BOSE and their patrons.

Why do so many people insist on taking the
extra effort to capitalize all the letters
in "Bose"?

On 26 Mar 2005 08:35:21 -0500, (Scott Dorsey) wrote:

dizzy wrote:

Whatever. What "satellite" speaker goes down to 20 Hz? It seems to
me that you have the mistaken notion that a "subwoofer" is for
reproducing infrasonic frequencies. It's not. It's for reproducing
frequencies below which most "normal" speakers are capable (which sure
the hell isn't 20 Hz).

Pretty much none of them do go down that far, and if they did, they'd
be large enough to be impractical. That's why the notion of the
satellite/sub is a basically misguided one.
--scott

Like I said: Clueless.

No Spam wrote:
"Ozzy 2005" wrote in message
...

It is simply incredible how any time BOSE is mentioned the threads are
infinitely long. AMAZING what some good propaganda can do to the crowd.
Long live BOSE and their patrons.


Why do so many people insist on taking the
extra effort to capitalize all the letters
in "Bose"?


To bother the trolls.

Scott Dorsey wrote:

Howard Ferstler wrote:
Generally, if the low-pass filtering is sharp enough (24 dB
per octave should do it), a crossover as high up as 90 Hz is
fine. The THX people have it at 80 Hz, just to make sure.

You can still hear directionality at 90 Hz. If you had one sub per channel,
you could easily do that. But if you're crossing over to a single sub you
are reducing your bass imaging severely.

Tell you what. Set your crossover to 90 Hz (or 80 Hz, if
your processor will go no higher), and then disconnect your
satellites and listen to a recording with standard bass
levels. Sit in your chair and see if you can locate the sub.
If you can, there are probably one or two reasons for this.
One: your sub is generating audible harmonics at higher
frequencies. Those would help to localize it. (Solution: get
a better sub.) Two: artifacts near the sub (knick knacks,
lamp shades, etc.) are generating sympathetic artifacts that
localize the sound in that direction. (Solution: relocate
the knick knacks.)

With a good sub (clean, low distortion) and the low-pass
filtering steep enough (24 dB per octave), it will be nearly
impossible to localize a sub.

The THX people are dealing with film soundtracks which are not exactly
the most demanding performance recordings out there. The THX standards
for the sub response are pretty terrifying too....

It was at the very bottom, because they wanted to mimic what
most theater subs can do. However, they have given up on
that. Actually, there was a second reason, too. They
prescribed a 12 dB rolloff below 35 Hz, because they assumed
that typical room gain would compensate. This is common
knowledge among acoustic engineers.

If you have a sub that is low-pass filtered at 20 Hz, just
what kind of musical sounds do you expect the thing to deal
with? For the most part, all it would reproduce is hall
rumble (not music) at frequencies that were felt rather than
heard. Is that all you want a sub to do?

Right, that's basically what a sub is _supposed_ to do. It's a _sub_ woofer
that kicks in below the point where the woofer stops.

Given that most program sources have little sound below 20
Hz, (aside from hall rumble), I would say that your sub
would not be doing much musical work.

PS: if you think that bass "images," disconnect your
satellites (all of them) and put on a bass-potent recording
with just the subwoofer playing. Try a variety of crossover
frequencies. I think that you will find that even that 90 Hz
point mentioned above will prevent the sub from being
localized, provided it generates distortion low enough to
not make undesirable harmonic artifacts audible.

A bunch of folks have done this sort of thing. There was actually a paper
at the last AES show from some folks in Greece who showed no effect on
typical material with the crossover moved up to 200 Hz.

Yes, but it would be easy to disprove this. Actually, the
guy who once captained Waveform subscribed to that approach,
which is why he mandated two subwoofers for his sub/sat
system. He (and those Greeks) are wrong, but so are you.

If you listen to minimalist classical recordings, the effect is quite
audible.

I once did that sort of thing with the satellites unplugged,
and thought that I could hear the sub outputting bass in the
right-front corner of my listening room. However, when I
went over to check it, I discovered that the sub was not
playing at all! Rather, my second sub, 20 feet away, in the
opposite corner, was what was playing. Yet, I had thought
that I could hear bass coming from the disconnected sub.
Yep, the power of suggestion can influence what we think we
hear from subwoofers.

Howard Ferstler

Howard Ferstler wrote:

Tell you what. Set your crossover to 90 Hz (or 80 Hz, if
your processor will go no higher), and then disconnect your
satellites and listen to a recording with standard bass
levels. Sit in your chair and see if you can locate the sub.
If you can, there are probably one or two reasons for this.
One: your sub is generating audible harmonics at higher
frequencies. Those would help to localize it. (Solution: get
a better sub.) Two: artifacts near the sub (knick knacks,
lamp shades, etc.) are generating sympathetic artifacts that
localize the sound in that direction. (Solution: relocate
the knick knacks.)

Not a fair test at all.

Much better is to put a set of subs around you in a meadow outside,
away from any large flat surfaces, and play pure tones in the 50-100
Hz region, then try and identify which of the subs is turned on.

You still have the problem of distortion from the speaker causing
higher frequency components that are easier to localize, though.
BUT, if that adds an artificial cue during the test, it will ALSO
add the same artificial cues during normal playback.

Having done this, I'll say that at 120 Hz it's very easy to tell
where the speaker is, at 60 Hz it's not too bad, and at 25 Hz you
can just barely do it but you can get it more often than not.

With a good sub (clean, low distortion) and the low-pass
filtering steep enough (24 dB per octave), it will be nearly
impossible to localize a sub.

If anything, I bet it's easier to localize the sub outdoors or in
an anechoic chamber than in a room, because of the number of room
reflections.

The THX people are dealing with film soundtracks which are not exactly
the most demanding performance recordings out there. The THX standards
for the sub response are pretty terrifying too....

It was at the very bottom, because they wanted to mimic what
most theater subs can do. However, they have given up on
that. Actually, there was a second reason, too. They
prescribed a 12 dB rolloff below 35 Hz, because they assumed
that typical room gain would compensate. This is common
knowledge among acoustic engineers.

Ahh, I was assuming you meant the theatrical THX standard, which is kind of
depressing. I honestly don't know the specs for the home systems, which
as far as I know don't include the room acoustics in the requirements.

If you listen to minimalist classical recordings, the effect is quite
audible.

I once did that sort of thing with the satellites unplugged,
and thought that I could hear the sub outputting bass in the
right-front corner of my listening room. However, when I
went over to check it, I discovered that the sub was not
playing at all! Rather, my second sub, 20 feet away, in the
opposite corner, was what was playing. Yet, I had thought
that I could hear bass coming from the disconnected sub.
Yep, the power of suggestion can influence what we think we
hear from subwoofers.

Absolutely, and that's what makes audio interesting.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Sat, 26 Mar 2005 20:38:36 +0000, Eiron wrote:

All of them are broken? Probably not a question of audio or swearing. If I
were you, I'd check for gremlins.

Stop listening to Maria Callas or keep the glasses topped up
as only an undamped wine glass will oscillate itself to death.

I will inform the sommelier.



Willie K. Yee, M.D. http://users.bestweb.net/~wkyee
Developer of Problem Knowledge Couplers for Psychiatry http://www.pkc.com
Webmaster and Guitarist for the Big Blue Big Band http://www.bigbluebigband.org

Willie K.Yee, M.D. said:

All of them are broken? Probably not a question of audio or swearing. If I
were you, I'd check for gremlins.

Stop listening to Maria Callas or keep the glasses topped up
as only an undamped wine glass will oscillate itself to death.

I will inform the sommelier.

Better the mistress of the house.

"No Spam" wrote:

"Ozzy 2005" wrote in message
...
It is simply incredible how any time BOSE is mentioned the threads are
infinitely long. AMAZING what some good propaganda can do to the crowd.
Long live BOSE and their patrons.

Why do so many people insist on taking the
extra effort to capitalize all the letters
in "Bose"?

To emphasize certain words I guess.

Regards Brian

Brian wrote in news:lrnb41hdq4kffa61bdjcj7r37j8tlgkgud@
4ax.com:

My Amplifier is rated at 20Hz to 20KHz.
Sony now sell Amplifiers that are build for a frequency response of
well beyond 20K. Sony call these group of items Extended Range.
www.sony.co.nz

My ears are nominally rated at 20Hz to 20kHz (and measured at something
closer to 35Hz to 15kHz).

There's always something new in Technology.

I believe that's spelled "Marketing hype." The Sony Extended Range systems
are more expensive than similar systems without the XR label, n'cest pas?

To put it another way: What's the most important difference between a Dodge
and a Chrysler? Answer: about $3000.


--
Email, Smarthosting, Web hosting for individuals and business:
Come to http://www.spamblocked.com
"I ran the Malicious Software Removal Tool, and now all my MS ware is
gone!"

Scott Dorsey wrote:

Howard Ferstler wrote:

Tell you what. Set your crossover to 90 Hz (or 80 Hz, if
your processor will go no higher), and then disconnect your
satellites and listen to a recording with standard bass
levels. Sit in your chair and see if you can locate the sub.
If you can, there are probably one or two reasons for this.
One: your sub is generating audible harmonics at higher
frequencies. Those would help to localize it. (Solution: get
a better sub.) Two: artifacts near the sub (knick knacks,
lamp shades, etc.) are generating sympathetic artifacts that
localize the sound in that direction. (Solution: relocate
the knick knacks.)

Not a fair test at all.

Much better is to put a set of subs around you in a meadow outside,
away from any large flat surfaces, and play pure tones in the 50-100
Hz region, then try and identify which of the subs is turned on.

This is a preposterous test, because it eliminates the room
gain and pressure-pot build up that any sub will generate in
a closed environment. It is those adjacent boundary
reflections that help to keep the sub's sound from being
localized. The long wavelengths at frequencies below about
90 Hz allow all of the reflections, plus the direct signals
from the sub, to hit the listener nearly simultaneously.
That is one big reason why the sub cannot be localized. Move
the sub outdoors and you eliminate the factors that help to
make it nonlocalized indoors.

You still have the problem of distortion from the speaker causing
higher frequency components that are easier to localize, though.

Yep. When somebody tells me that they can localize a sub
when it is playing signals below 80 Hz I tend to believe
that the sub is generating harmonic artifacts at higher
frequencies that help to localize it. If, for example, it is
emitting a 50 Hz signal there will be harmonics that are
easy to locate. Heck, even the wall behind it may be
emitting higher-order harmonics as the drywall and pictures
hanging there vibrate.

BUT, if that adds an artificial cue during the test, it will ALSO
add the same artificial cues during normal playback.

Sure. This is why one should get a sub with low distortion.
Note that when one reconnects the satellites their
overwhelmingly louder sounds at upper-bass frequencies and
still higher will allow the Franssen Effect (and the
precedence effect, too, if the sub is further from the
listener than the satellites) to mask any minor localization
clues coming from the sub, even if it has some minor
harmonic artifacts.

Having done this, I'll say that at 120 Hz it's very easy to tell
where the speaker is, at 60 Hz it's not too bad, and at 25 Hz you
can just barely do it but you can get it more often than not.

I simply disagree. I find it hard to believe that you
believe this to be the case. Have you actually done the
satellite disconnect procedure I outlined? Remember, as I
said before, when I did a test like that once I thought a
subwoofer was playing that was turned off and the one that
was playing was 20 feet from it. So goes the power of
suggestion, even with skeptical cranks like me.

With a good sub (clean, low distortion) and the low-pass
filtering steep enough (24 dB per octave), it will be nearly
impossible to localize a sub.

If anything, I bet it's easier to localize the sub outdoors or in
an anechoic chamber than in a room, because of the number of room
reflections.

Right. However, this anomaly is irrelevant, since most of us
listen to subs (and music) in enclosed spaces. Sure, you can
come up with a killer test (subs outdoors) that will support
your claims. However, those claims are not relevant to what
we listen to indoors.

The THX people are dealing with film soundtracks which are not exactly
the most demanding performance recordings out there. The THX standards
for the sub response are pretty terrifying too....

It was at the very bottom, because they wanted to mimic what
most theater subs can do. However, they have given up on
that. Actually, there was a second reason, too. They
prescribed a 12 dB rolloff below 35 Hz, because they assumed
that typical room gain would compensate. This is common
knowledge among acoustic engineers.

Ahh, I was assuming you meant the theatrical THX standard, which is kind of
depressing. I honestly don't know the specs for the home systems, which
as far as I know don't include the room acoustics in the requirements.

They did. However, current THX certified units can go as
flat down into the low bass range as the manufacturer wants.
The mandated rolloff below 35 Hz has been deleted from the
requirements. Remember, that spec was there to compensate
for typical room gain below about 35 Hz.

Incidentally, one chapter in my The Home Theater Companion
book (Schirmer Books, 1997) was devoted entirely to the THX
parameters. Well, actually, only 11 pages of chapter 7,
which dealt with Dolby Surround and surround in general.

Howard Ferstler

Howard Ferstler wrote:
Scott Dorsey wrote:

Much better is to put a set of subs around you in a meadow outside,
away from any large flat surfaces, and play pure tones in the 50-100
Hz region, then try and identify which of the subs is turned on.

This is a preposterous test, because it eliminates the room
gain and pressure-pot build up that any sub will generate in
a closed environment.

Yes, this is the point!

It is those adjacent boundary
reflections that help to keep the sub's sound from being
localized. The long wavelengths at frequencies below about
90 Hz allow all of the reflections, plus the direct signals
from the sub, to hit the listener nearly simultaneously.
That is one big reason why the sub cannot be localized. Move
the sub outdoors and you eliminate the factors that help to
make it nonlocalized indoors.

Okay, I'll buy that. That makes perfectly reasonable sense, that the
room screws up the coherency enough to make localization impossible under
the best of circumstances.

To take the opposing view, though, you could also argue that the whole point
of proper and careful room set-up is to minimize these effects and improve
localization.

Having done this, I'll say that at 120 Hz it's very easy to tell
where the speaker is, at 60 Hz it's not too bad, and at 25 Hz you
can just barely do it but you can get it more often than not.

I simply disagree. I find it hard to believe that you
believe this to be the case. Have you actually done the
satellite disconnect procedure I outlined? Remember, as I
said before, when I did a test like that once I thought a
subwoofer was playing that was turned off and the one that
was playing was 20 feet from it. So goes the power of
suggestion, even with skeptical cranks like me.

I have done the outdoor test I outlined above, but I haven't done the
procedure you outlined. But I can believe very well that the room effects
can stymie localization at low frequencies. If you're arguing that's the
limiting factor I pretty much agree with you.

With a good sub (clean, low distortion) and the low-pass
filtering steep enough (24 dB per octave), it will be nearly
impossible to localize a sub.

If anything, I bet it's easier to localize the sub outdoors or in
an anechoic chamber than in a room, because of the number of room
reflections.

Right. However, this anomaly is irrelevant, since most of us
listen to subs (and music) in enclosed spaces. Sure, you can
come up with a killer test (subs outdoors) that will support
your claims. However, those claims are not relevant to what
we listen to indoors.

I've seen some listening rooms that were pretty clean on the low end,
though by no means dead. I've also seen some that were horrible. I'm
arguing from the standpoint of having a theoretically perfect room, of
course.

Ahh, I was assuming you meant the theatrical THX standard, which is kind of
depressing. I honestly don't know the specs for the home systems, which
as far as I know don't include the room acoustics in the requirements.

They did. However, current THX certified units can go as
flat down into the low bass range as the manufacturer wants.
The mandated rolloff below 35 Hz has been deleted from the
requirements. Remember, that spec was there to compensate
for typical room gain below about 35 Hz.

Some of them can, but they don't necessarily have to. That's basically my
issue with THX.... it's really just a very minimal standard for the equipment
and hall. It doesn't take all that much to meet it, but there's a lot of other
gear out there that could meet it handily which hasn't been certified. Yes,
subs with real sub-bass response now can meet the specs, but by the same token
the Bose Bass Cannon also meets them.

Note also that if you're running optical sound tracks, having a rolloff
below 35 Hz is a good idea. If nothing else, it keeps the audience from
losing their lunch when a splice goes over the soundhead.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Scott Dorsey wrote:

Howard Ferstler wrote:
Scott Dorsey wrote:

Much better is to put a set of subs around you in a meadow outside,
away from any large flat surfaces, and play pure tones in the 50-100
Hz region, then try and identify which of the subs is turned on.

This is a preposterous test, because it eliminates the room
gain and pressure-pot build up that any sub will generate in
a closed environment.

Yes, this is the point!

OK, so your point is that a test can be set up that will
allow low bass to be localized. The problem with that test
is that it does not apply to real-world, indoor listening
situations.

It is those adjacent boundary
reflections that help to keep the sub's sound from being
localized. The long wavelengths at frequencies below about
90 Hz allow all of the reflections, plus the direct signals
from the sub, to hit the listener nearly simultaneously.
That is one big reason why the sub cannot be localized. Move
the sub outdoors and you eliminate the factors that help to
make it nonlocalized indoors.

Okay, I'll buy that. That makes perfectly reasonable sense, that the
room screws up the coherency enough to make localization impossible under
the best of circumstances.

It does not screw up the coherency at all, at least if we
are talking about localization. When it comes to
localization the room works WITH us, and not against us. It
allows a single sub to be used, with the satellites
(courtesy of the Franssen Effect) to determine
bass-localization clues.

To take the opposing view, though, you could also argue that the whole point
of proper and careful room set-up is to minimize these effects and improve
localization.

There is no need to improve localization with the low bass,
or any bass below about 90 Hz (assuming a 24 dB low-pass
rolloff with that frequency; with still lower frequencies a
less abrupt cutoff would work OK). The satellites, which
deal with the attack part of any typical bass signals,
handle the localization.

Having done this, I'll say that at 120 Hz it's very easy to tell
where the speaker is, at 60 Hz it's not too bad, and at 25 Hz you
can just barely do it but you can get it more often than not.

I simply disagree. I find it hard to believe that you
believe this to be the case. Have you actually done the
satellite disconnect procedure I outlined? Remember, as I
said before, when I did a test like that once I thought a
subwoofer was playing that was turned off and the one that
was playing was 20 feet from it. So goes the power of
suggestion, even with skeptical cranks like me.

I have done the outdoor test I outlined above, but I haven't done the
procedure you outlined. But I can believe very well that the room effects
can stymie localization at low frequencies. If you're arguing that's the
limiting factor I pretty much agree with you.

Well, we at least agree there. Where we do not agree
involves your contention that an outdoor test means anything
in terms of real-world performance in typical (or even
superior) listening rooms.

With a good sub (clean, low distortion) and the low-pass
filtering steep enough (24 dB per octave), it will be nearly
impossible to localize a sub.

If anything, I bet it's easier to localize the sub outdoors or in
an anechoic chamber than in a room, because of the number of room
reflections.

Right. However, this anomaly is irrelevant, since most of us
listen to subs (and music) in enclosed spaces. Sure, you can
come up with a killer test (subs outdoors) that will support
your claims. However, those claims are not relevant to what
we listen to indoors.

I've seen some listening rooms that were pretty clean on the low end,
though by no means dead. I've also seen some that were horrible. I'm
arguing from the standpoint of having a theoretically perfect room, of
course.

Even a theoretically perfect room would not do what you
want. By definition, a room would mask localization clues in
the low-bass range. Well, I suppose that a room the size of
an airplane hanger would work for you.

Ahh, I was assuming you meant the theatrical THX standard, which is kind of
depressing. I honestly don't know the specs for the home systems, which
as far as I know don't include the room acoustics in the requirements.

They did. However, current THX certified units can go as
flat down into the low bass range as the manufacturer wants.
The mandated rolloff below 35 Hz has been deleted from the
requirements. Remember, that spec was there to compensate
for typical room gain below about 35 Hz.

Some of them can, but they don't necessarily have to.

Correct. There is no mandated standard for extension into
the ultra-low range. Any sub that is flat to 35 Hz, with the
rolloff below that frequency no steeper than 12 dB per
octave will pass the response-curve requirements. Of course,
there are additional requirements involving distortion and
max output, as well as hookup options.

That's basically my
issue with THX.... it's really just a very minimal standard for the equipment
and hall. It doesn't take all that much to meet it, but there's a lot of other
gear out there that could meet it handily which hasn't been certified.

Sure. Even some full-range speakers (such as my Allison
IC-20 systems or my Dunlavy Cantata systems) can probably
deal with all of the THX requirements in the low-bass range.

Yes,
subs with real sub-bass response now can meet the specs, but by the same token
the Bose Bass Cannon also meets them.

I am not familiar with that unit, but the standard Bose
"subwoofers" I have read about probably cannot.

Note also that if you're running optical sound tracks, having a rolloff
below 35 Hz is a good idea. If nothing else, it keeps the audience from
losing their lunch when a splice goes over the soundhead.

Yep. The old theater standard did take that into account.
Those were the analog days, of course.

Howard Ferstler

Howard Ferstler wrote:

Well, we at least agree there. Where we do not agree
involves your contention that an outdoor test means anything
in terms of real-world performance in typical (or even
superior) listening rooms.

As much as I have learned from Scott, which is plenty, I agree with you
here. He seems to have a hang up on what could/should be. I think it is
useless to discuss this stuff in terms of absolutes and *potential*
performance under ideal conditions. This is not real life. How it
performs in normal conditions or even marginally optimized conditions is
much more relevant. In which case nobody is going to identify the
position of a sub woofer at 20 hz, in the extremely rare case there is
even anything there. I would venture to say that even at 100 hz
localization of the sub would be unlikely.

To go back to the original point, there have been plenty of
satellite/sub systems designed that compare favorably with the very best
speakers made, i.m.o.

Joe Sensor wrote:
Howard Ferstler wrote:

Well, we at least agree there. Where we do not agree
involves your contention that an outdoor test means anything
in terms of real-world performance in typical (or even
superior) listening rooms.

As much as I have learned from Scott, which is plenty, I agree with you
here. He seems to have a hang up on what could/should be. I think it is
useless to discuss this stuff in terms of absolutes and *potential*
performance under ideal conditions. This is not real life. How it
performs in normal conditions or even marginally optimized conditions is
much more relevant.

I dunno, I started out discussing things under ideal circumstances, and
I think that is the whole point of this thread. It's not supposed to be
about real life.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

"Scott Dorsey" wrote in message
...


I dunno, I started out discussing things under ideal circumstances, and
I think that is the whole point of this thread. It's not supposed to be
about real life.

I agree. As near an ideal listening room as possible is what we should be
aiming for, and should be the criteria for comparison and testing.

Otherwise it's like saying that **** isn't **** because it doesn't taste
like **** if you put enough perfume on it.


geoff

Joe Sensor said:

Howard Ferstler wrote:

Well, we at least agree there. Where we do not agree
involves your contention that an outdoor test means anything
in terms of real-world performance in typical (or even
superior) listening rooms.

As much as I have learned from Scott, which is plenty, I agree with you
here. He seems to have a hang up on what could/should be. I think it is
useless to discuss this stuff in terms of absolutes and *potential*
performance under ideal conditions. This is not real life. How it
performs in normal conditions or even marginally optimized conditions is
much more relevant.


Hmmm.......I see some resemblance between the above statements and
taking double blind tests vs. casual listening as it is normally done
under domestical circumstances.

A DBT is NOT equal to casual listening.
Thanks for reinforcing my thoughts about this guys! ;-)

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Sander deWaal" wrote in message


A DBT is NOT equal to casual listening.

Right, the DBT is for all intents and purposes vastly superior to
casual listening.

Howard Ferstler wrote:
Scott Dorsey wrote:

Okay, I'll buy that. That makes perfectly reasonable sense, that the
room screws up the coherency enough to make localization impossible under
the best of circumstances.

It does not screw up the coherency at all, at least if we
are talking about localization. When it comes to
localization the room works WITH us, and not against us. It
allows a single sub to be used, with the satellites
(courtesy of the Franssen Effect) to determine
bass-localization clues.

Aha! Here is our disagreement! I look upon stereophony as being a
method of reproducing, as accurately as possible, the 3-dimensional
wavefront measured at a single point in space in a hall. To be honest,
it's not a very accurate one at all, but the whole notion of reproducing
where a wave is coming from and the spectrum of that wave is important.

By coherency I mean just that... that if there was a single pulse
coming from one direction that it should be reproduced the same way.
Yes, in a real world application the room effects are going to screw
up the accuracy at low frequencies, and the room effects on playback
are not predictable.

You're looking on stereophony as merely needing to reproduce the impression
of an accurate soundstage. Which is a perfectly valid viewpoint as well.

My argument is that the room effects on playback are unpredictable and
therefore can't be relied on.

Well, we at least agree there. Where we do not agree
involves your contention that an outdoor test means anything
in terms of real-world performance in typical (or even
superior) listening rooms.

My contention is that it _should_ and that we should be doing more
to improve listening rooms if it doesn't. I'm sure it very seldom
does, but that's no reason to rely on higher frequency components
and "room smear" for localization.

Even a theoretically perfect room would not do what you
want. By definition, a room would mask localization clues in
the low-bass range. Well, I suppose that a room the size of
an airplane hanger would work for you.

I work in studios like that all the time, and what is interesting is
that they are actually _not_ dead on the low end... they are often
quite live at low frequencies, but with an RT long enough to make
for very interesting false localization cues at low frequencies sometimes.

Sure. Even some full-range speakers (such as my Allison
IC-20 systems or my Dunlavy Cantata systems) can probably
deal with all of the THX requirements in the low-bass range.

Again, the only THX specs I have seen are the theatrical ones, which
mandate also intensity levels and radiation patterns....

Yes,
subs with real sub-bass response now can meet the specs, but by the same token
the Bose Bass Cannon also meets them.

I am not familiar with that unit, but the standard Bose
"subwoofers" I have read about probably cannot.

Look backstage at your local multiplex. They are basically two organ
pipes together with a single driver exciting them. They are, well,
kind of nasty.

Note also that if you're running optical sound tracks, having a rolloff
below 35 Hz is a good idea. If nothing else, it keeps the audience from
losing their lunch when a splice goes over the soundhead.

Yep. The old theater standard did take that into account.
Those were the analog days, of course.

I hate to tell yoou this, but more than half of the stuff being shown
at our local multiplex is in analogue optical. Often even when DIGITAL
is listed on the marquee.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Tue, 29 Mar 2005 11:51:11 -0500, Arny Krueger
wrote:
"Sander deWaal" wrote in message


A DBT is NOT equal to casual listening.

Right, the DBT is for all intents and purposes vastly superior to
casual listening.


And there's absolutely nothing wrong with a Bose speaker cabinet that
wouldn't be corrected by running it through a wood chipper.

Arny Krueger wrote:

A DBT is NOT equal to casual listening.

Right, the DBT is for all intents and purposes vastly superior to
casual listening.


For what/who's purpose?

Scott Dorsey wrote:


You're looking on stereophony as merely needing to reproduce the impression
of an accurate soundstage. Which is a perfectly valid viewpoint as well.

I don't see how stereo can do anything but create the impression.

To recreate the original accurately, you would need to have multiple
full range drivers located exactly in the positions of the original
instruments, and the recording would have to be with microphones at the
same points. This would be quite an array of speakers for, say, a full
orchestra. And you would have to play the system back in the same room.

Joe Sensor wrote:
Scott Dorsey wrote:

You're looking on stereophony as merely needing to reproduce the impression
of an accurate soundstage. Which is a perfectly valid viewpoint as well.

I don't see how stereo can do anything but create the impression.

As I said, it can't do that great a job, since you are only able to
reproduce the pressure at two points in space.,

To recreate the original accurately, you would need to have multiple
full range drivers located exactly in the positions of the original
instruments, and the recording would have to be with microphones at the
same points. This would be quite an array of speakers for, say, a full
orchestra. And you would have to play the system back in the same room.

This is, in fact, called sonic holography (no relation to the Bob Carver
misuse of the term). To do it perfectly, you would need enough drivers
that they could be spaced less than a half-wave apart at the highest
frequency of interest.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

"Joe Sensor" wrote in message

Arny Krueger wrote:

A DBT is NOT equal to casual listening.

Right, the DBT is for all intents and purposes vastly superior to
casual listening.


For what/who's purpose?

For the purpose of determining audible differences due to various
pieces of audio gear.

****-for-Brains said:

A DBT is NOT equal to casual listening.

Right, the DBT is for all intents and purposes vastly superior to
casual listening.

Especially if you participate in the eye-gouging rituals.

Joe Sensor said:

Right, the DBT is for all intents and purposes vastly superior to
casual listening.

For what/who's purpose?

The Krooborg's purpose is to spread his class-warfare borgma. Nothing
whatever to do with music.

On Tue, 29 Mar 2005 14:32:09 -0500, "Arny Krueger"
wrote:

"Joe Sensor" wrote in message

Arny Krueger wrote:

A DBT is NOT equal to casual listening.

Right, the DBT is for all intents and purposes vastly superior to
casual listening.


For what/who's purpose?

For the purpose of determining audible differences due to various
pieces of audio gear.

By definition, casual listening isn't used for such purposes, so
there's no ranking to be done.

Scott Dorsey wrote:

I hate to tell you this, but more than half of the stuff being shown
at our local multiplex is in analogue optical. Often even when DIGITAL
is listed on the marquee.


Because of that 8-foot-wide screen of mine in my main AV
room (not to mention 2000 watts of audio power spread out
over 8 channels), I have not been to a theater to watch a
movie in years. I can patiently and happily wait for
first-run movies to show up on DVD.

The last time I did go I said to myself, "what a mess."
Well, it was not a THX theater.

Howard Ferstler

Joe Sensor wrote:

Arny Krueger wrote:

A DBT is NOT equal to casual listening.

Right, the DBT is for all intents and purposes vastly superior to
casual listening.

For what/who's purpose?

To help learn what does and does not matter in the realm of
subjective-sound audio. In other words, for the purpose of
educating the participant.

Howard Ferstler

Joe Sensor wrote:

Scott Dorsey wrote:

You're looking on stereophony as merely needing to reproduce the impression
of an accurate soundstage. Which is a perfectly valid viewpoint as well.

I don't see how stereo can do anything but create the impression.

To recreate the original accurately, you would need to have multiple
full range drivers located exactly in the positions of the original
instruments, and the recording would have to be with microphones at the
same points. This would be quite an array of speakers for, say, a full
orchestra. And you would have to play the system back in the same room.

The best you can do is obtain an approximation. However, the
more channels the better if we want the approximation to be
as good as possible. Five are OK. Six are a bit better.
Seven better yet, and eight still better. I think that Tom
Holman is up to ten with his latest design, plus two subs.

Howard Ferstler

dave weil wrote:

On Tue, 29 Mar 2005 14:32:09 -0500, "Arny Krueger"
wrote:

"Joe Sensor" wrote in message

Arny Krueger wrote:

A DBT is NOT equal to casual listening.

Right, the DBT is for all intents and purposes vastly superior to
casual listening.

For what/who's purpose?

For the purpose of determining audible differences due to various
pieces of audio gear.

By definition, casual listening isn't used for such purposes, so
there's no ranking to be done.

You can get around to that casual listening after you do the
DBT work and determine what does and does not matter as it
involves components in the system. Of course, one may
already have all the gear they need, and so the DBT approach
would be a waste of time if all that mattered was
intelligent shopping and the saving of money.

However, the lack of a need for new gear notwithstanding, I
would think that curious audio buffs would be interested in
DBT work just to better educate themselves about audio and
the principles that are involved. The best way to test
belief systems that mythologize amps and wires is to get
involved in some DBT work, level-matched, of course.

Howard Ferstler

Brother Horace the Intensely Anal said:

For what/who's purpose?

To help learn what does and does not matter in the realm of
subjective-sound audio.

When was the last time you stopped to smell the roses, Harold? And I mean
that literally. "Smell the roses" is not a euphemism for you-know-what.

Howard Ferstler wrote




The best way to test belief systems that mythologize amps
and wires is to get involved in some DBT work, level-matched,
of course.


What if the person trying out is deaf and a habitual lying hypocrite
like... like... you?

On 3/29/05 10:06 PM, in article
, "EddieM"
wrote:

What if the person trying out is deaf and a habitual lying hypocrite
like... like... you?

Eddie and all you Kids, let's edit those crosspost headers.
It's Easy,
It's Fun
and it makes you smarter than the dolt who snuck so many unwanted
destinations in there!
Go for it!
Thanks!

On 3/29/05 9:46 PM, in article ,
"George M. Middius" wrote:

When was the last time you stopped to smell the roses, Harold? And I mean
that literally. "Smell the roses" is not a euphemism for you-know-what.


George and all you Kids, let's edit those crosspost headers.
It's Easy,
It's Fun
and it makes you smarter than the dolt who snuck so many unwanted
destinations in there!
Go for it!
Thanks!

EddieM said:

The best way to test belief systems that mythologize amps
and wires is to get involved in some DBT work, level-matched,
of course.

What if the person trying out is deaf and a habitual lying hypocrite
like... like... you?

Brother Ferstler hopes to be promoted one day to full-fledged moron. In the
meantime, that's his epithet of utmost respect.

SSJVCmag said:

When was the last time you stopped to smell the roses, Harold? And I mean
that literally. "Smell the roses" is not a euphemism for you-know-what.

George and all you Kids, let's edit those crosspost headers.

Are you seriously telling us you want Ferstler and Krooger all for
yourself?

"Howard Ferstler" wrote in message

dave weil wrote:

On Tue, 29 Mar 2005 14:32:09 -0500, "Arny Krueger"

wrote:

"Joe Sensor" wrote in message

Arny Krueger wrote:

A DBT is NOT equal to casual listening.

Right, the DBT is for all intents and purposes vastly superior
to
casual listening.

For what/who's purpose?

For the purpose of determining audible differences due to various
pieces of audio gear.

By definition, casual listening isn't used for such purposes, so
there's no ranking to be done.

Revisionism and retrenching, I love it!

For years we've been told by Middius, Sackman, etc. perhaps even Weil;
that DBTs aren't appropriate for ranking equipment because they don't
involve the same kind of listening as listening for enjoyment (i.e.,
casual listening). Now Weil finally agrees with me that casual
listening and listening to rank equipment are simply and inherently
two different things.

You can get around to that casual listening after you do the
DBT work and determine what does and does not matter as it
involves components in the system.

Agreed. Also, casual listening can help set the stage for more
rigorous comparison tests. I hear something while listening casually,
and I think that maybe the music at ear would be especially good to
use during a more formal comparision test.


Of course, one may
already have all the gear they need, and so the DBT approach
would be a waste of time if all that mattered was
intelligent shopping and the saving of money.

The audio DBT was devised by myself and my associates as a maximum
effort approach to ranking components, and component technologies. ABX
was the form of DBT that worked best for us.

However, the lack of a need for new gear notwithstanding, I
would think that curious audio buffs would be interested in
DBT work just to better educate themselves about audio and
the principles that are involved.

Good-sounding systems are listened into existence. Critical listening
is very important when new components are being chosen, system are
configured, and optimal interconnection and placement are determined.
DBTs are not only good for making choices they are also effective at
training people how to listen for important sonic differences.

The best way to test
belief systems that mythologize amps and wires is to get
involved in some DBT work, level-matched, of course.

Agreed.

"George M. Middius" wrote in message

Joe Sensor said:

Right, the DBT is for all intents and purposes vastly superior to
casual listening.

For what/who's purpose?

The Krooborg's purpose is to spread his class-warfare borgma.

Let's look at this situation. Middius is so ashamed of his life and
lifestyle that he makes a big secret of it. Do you know where he
lives, what his credentials and occupation is, or what his status in
life is? All we've seen lately is examples of his belief that the most
important thing about audio gear is the discount from list. Doesn't
this position Middius in the lower middle class?

OTOH, I am a long-time resident of the nationally-known upper
middle-class community Grosse Pointe Woods Michigan, a graduate
engineer with signifcant work on an advanced degree, an information
technology professional with over 30 years of experience, father of
three children who are college graduates, all employed professionally,
all with advanced degrees or work in progress including one PhD, and
the owner of a good-sized historic home that is currently undergoing a
six-figure rennovation.

So, exactly what lower class do I represent, and what upper class am I
supposed at war with?

Nothing whatever to do with music.

Class warfare does indeed have nothing to do with music. Music is
there to be enjoyed by all. The enjoyment of specific works of music
cuts across class boundaries.

What the heck is Middius ranting about, anyhow?

On Tue, 29 Mar 2005 21:30:19 -0500, Howard Ferstler
wrote:

However, the lack of a need for new gear notwithstanding, I
would think that curious audio buffs would be interested in
DBT work just to better educate themselves about audio and
the principles that are involved. The best way to test
belief systems that mythologize amps and wires is to get
involved in some DBT work, level-matched, of course.

Unless you're commenting on things like Quad speakers. Then all bets
are off.