[Brian Running]

That we have different sets of ears is a glorious thing. Adding that
kind of distortion to a cheap PA just drives me out of the room.

Better that, than my bass playing, I guess. ;-)

[hank alrich]

Brian Running wrote:

That we have different sets of ears is a glorious thing. Adding that
kind of distortion to a cheap PA just drives me out of the room.

Better that, than my bass playing, I guess. ;-)

Sorry, Brian, even never having heard you play, I'll take your bass
playing over the BBE! grinning, but not kidding

--
ha

[Brian Running]

Yes. The BBE can be a real help for improving intelligibility of material
with rolled-off top end. I have taken badly damaged acetate recordings
that had nothing above 4 KC left due to wear, and made them listenable
with the exciters. It can be great to improve the voice intelligibility of
remotes made over POTS phone lines too.

The BBE adds fake high end when there is no high end there, and as such it
can be useful for salvaging material that has no high end. The problem comes
when you put it on something that DOES have high end.

Okay, then we really don't disagree.

[Anahata]

Richard Amirault wrote:
Question ... are all these objections to only the BBE Sonic Maximizer, or do
they apply to other brands?

They apply to any effects processing. It's only good if it sounds good,
and there's no magic device that makes everything sound better.

What is it about the BBE that convinces so many people it's the holy
grail or perpetual motion machine or something?

Anahata

[Scott Dorsey]

Anahata wrote:
Richard Amirault wrote:
Question ... are all these objections to only the BBE Sonic Maximizer, or do
they apply to other brands?

They apply to any effects processing. It's only good if it sounds good,
and there's no magic device that makes everything sound better.

What is it about the BBE that convinces so many people it's the holy
grail or perpetual motion machine or something?

I think it's cocaine.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Brian Running]

What is it about the BBE that convinces so many people it's the holy
grail or perpetual motion machine or something?

The same thing that makes the converse true, also: What is it about the
BBE that convinces so many people that it has no useful application,
ever, at any time? It's what it does to the sound, obviously.

I remember reading the liner notes in the Eagles' "Long Run" back in '79
or '80, whenever it came out, and there was a little blurb in there that
emphatically said, "NOT recorded using the Aphex Aural Exciter." I had
no idea what it was at the time, but obviously, the Eagles and their
producer were pretty proud to have bucked the trend and not used it.

Whatever gets you the sound you want.

[GregS]

In article , Brian Running wrote:
What is it about the BBE that convinces so many people it's the holy
grail or perpetual motion machine or something?

The same thing that makes the converse true, also: What is it about the
BBE that convinces so many people that it has no useful application,
ever, at any time? It's what it does to the sound, obviously.

I remember reading the liner notes in the Eagles' "Long Run" back in '79
or '80, whenever it came out, and there was a little blurb in there that
emphatically said, "NOT recorded using the Aphex Aural Exciter." I had
no idea what it was at the time, but obviously, the Eagles and their
producer were pretty proud to have bucked the trend and not used it.

Whatever gets you the sound you want.

Back in about 1978 I installed a new Blaupunkt head unit in my 280Z.
I could not get any FM stations where I lived. On my first trip to Vegas,
I really liked using the FM. There was a Dolby button on the FM. When
you pressed in on the button, the highs would magically increase. This
is in reversed action to what I would think it should have done, and there
were no Dolby stations anyway. But, the system did sound better with the
Dolby energized. Can't say I never left the Dolby off when listening
to tapes.I just wanted to say that the sound was very similar to the BBE
sound, and in this case, improved things.

greg

[Paul Stamler]

"Ty Ford" wrote in message
. ..

I have had good experience with revitalizing audio from a cassette
portastudio and using much less than you thought you needed.

The Aphex Aural Exciter was originally "designed" when a chip went up
during
a Linda Ronstadt mixing session. One channel sounded like crap, the other
OK.
When they mono-summed the two, they liked the effect.

They found that the chip was causing a lot of harmonic distortion. The
first
boxes were rented on a "per minute" basis to professional recording
studios.

A little bit of history..

I believe Aural Exciters were introduced before Linda Ronstadt emerged as a
solo artist, but I might be wrong. The folk from Aphex have also said that
the Aural Exciter was invented when the designer accidentally mis-wired a
Dynaco Mark III power amplifier kit and was wowed by the sound. Occasionally
they say it was a Dynaco preamp.

My guess is that all of these stories are hogwash.

Peace,
Paul

[Ludwig77]

Walt wrote:
Ludwig77 wrote:

I'm really surprised to hear all of you expressing distaste for the
Sonic Maximizer. I certainly love it within my guitar rig. If it adds
distortion, it isn't to the degree that it distorts clean tones.

Hey, I'm a rock and roller from way back. I love distorted electric
guitars.

What I don't love are distorted vocals, distorted drums, etc.

The BBE box is a fine guitar effect. If you like it, go for it. Just
don't use it on everything. You don't try to sing through a Marshall
stack, do you?

//Walt

But Walt, the BBE doesn't distort like a Marshall. You can't even hear
it distorting. All you can hear is the highs brightening up and the
lows getting thicker.

[Walt]

Ludwig77 wrote:
Walt wrote:
Ludwig77 wrote:

I'm really surprised to hear all of you expressing distaste for the
Sonic Maximizer. I certainly love it within my guitar rig. If it adds
distortion, it isn't to the degree that it distorts clean tones.

Hey, I'm a rock and roller from way back. I love distorted electric
guitars.

What I don't love are distorted vocals, distorted drums, etc.

The BBE box is a fine guitar effect. If you like it, go for it. Just
don't use it on everything. You don't try to sing through a Marshall
stack, do you?

But Walt, the BBE doesn't distort like a Marshall.

Agreed. It has it's own unique way of distorting. Most distortion
boxen do.

You can't even hear it distorting.

*Some people* can't hear it distorting. Or they don't recognize the
phenemenon as distortion.

All you can hear is the highs brightening up and the
lows getting thicker.

i.e. distortion.


//Walt

[Geoff]

Paul Stamler wrote:
"Ty Ford" wrote in message
. ..

I have had good experience with revitalizing audio from a cassette
portastudio and using much less than you thought you needed.

The Aphex Aural Exciter was originally "designed" when a chip went
up during a Linda Ronstadt mixing session. One channel sounded like
crap, the other OK. When they mono-summed the two, they liked the
effect.

They found that the chip was causing a lot of harmonic distortion.
The first boxes were rented on a "per minute" basis to professional
recording studios.

A little bit of history..

I believe Aural Exciters were introduced before Linda Ronstadt
emerged as a solo artist, but I might be wrong. The folk from Aphex
have also said that the Aural Exciter was invented when the designer
accidentally mis-wired a Dynaco Mark III power amplifier kit and was
wowed by the sound. Occasionally they say it was a Dynaco preamp.

Grover Washington Jr "Winelight" must have been th first major release to
'feature' it in sleeve notes. Didn't need to.

geoff

[hank alrich]

Ludwig77 wrote:

But Walt, the BBE doesn't distort like a Marshall.

Right, it's distortion is different than that of a Marshall guitar amp.

You can't even hear
it distorting. All you can hear is the highs brightening up and the
lows getting thicker.

That's not what I hear.

--
ha

[Ty Ford]

On Wed, 8 Nov 2006 12:56:46 -0500, Paul Stamler wrote
(in article ):

"Ty Ford" wrote in message
. ..

I have had good experience with revitalizing audio from a cassette
portastudio and using much less than you thought you needed.

The Aphex Aural Exciter was originally "designed" when a chip went up
during
a Linda Ronstadt mixing session. One channel sounded like crap, the other
OK.
When they mono-summed the two, they liked the effect.

They found that the chip was causing a lot of harmonic distortion. The
first
boxes were rented on a "per minute" basis to professional recording
studios.

A little bit of history..

I believe Aural Exciters were introduced before Linda Ronstadt emerged as a
solo artist, but I might be wrong. The folk from Aphex have also said that
the Aural Exciter was invented when the designer accidentally mis-wired a
Dynaco Mark III power amplifier kit and was wowed by the sound. Occasionally
they say it was a Dynaco preamp.

My guess is that all of these stories are hogwash.

Peace,
Paul



I got my version from Marvin Caesar. Aphex owner.

Regards,

Ty Ford


-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

[Richard Amirault]

"Brian Running" wrote ..
The same thing that makes the converse true, also: What is it about the
BBE that convinces so many people that it has no useful application, ever,
at any time? It's what it does to the sound, obviously.

I remember reading the liner notes in the Eagles' "Long Run" back in '79
or '80, whenever it came out, and there was a little blurb in there that
emphatically said, "NOT recorded using the Aphex Aural Exciter." I had no
idea what it was at the time, but obviously, the Eagles and their producer
were pretty proud to have bucked the trend and not used it.

Whatever gets you the sound you want.

General comment on this thread .. I am not a sound engineer .. I'm just
bearly a sound man. I read this list in the hope to pick up bits of
information that might prove useful. I *do* have a small .. 100 watt .. PA
system .. and it has a BBE Sonic Maximizer in the chain.

In another life I was a lightman at a disco / nightclub. I had worked in
this particular club for *months* and, of course, had heard the sound system
all night for 2 or 3 nights a week. At one point the folks who installed
the system came in and added an Aphex Aural Exciter ... the difference was
obvious the first time we turned the system on. It sounded *much* better ..
at least to my untrained ears. I remember thinking "It sounds *much*
clearer than before."

As far as my system?? I dunno .. I don't use it that much, that often, to
have heard any difference when I installed the BBE, but other folks have
commented that my system sounds noticably better than others (with much more
power) when used in the same venue.

--
Richard Amirault N1JDU Boston,
MA, USA
n1jdu.org "Go Fly A Kite"

[Scott Dorsey]

Richard Amirault wrote:
In another life I was a lightman at a disco / nightclub. I had worked in
this particular club for *months* and, of course, had heard the sound system
all night for 2 or 3 nights a week. At one point the folks who installed
the system came in and added an Aphex Aural Exciter ... the difference was
obvious the first time we turned the system on. It sounded *much* better ..
at least to my untrained ears. I remember thinking "It sounds *much*
clearer than before."

Yes. This is a sign that something else is wrong in the chain. If it
doesn't sound harsh, it's compensating for something else. Find out
what that thing is, and fix it.

Now, that something might be the speaker system, or it might be the original
recording quality too.

As far as my system?? I dunno .. I don't use it that much, that often, to
have heard any difference when I installed the BBE, but other folks have
commented that my system sounds noticably better than others (with much more
power) when used in the same venue.

That may be the case, but the BBE may not have anything to do with that.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Skler]

"Ludwig77" wrote in message
ps.com...
I have a BBE Sonic Maximizer that I use in my guitar rig.

As I understand it, the Maximizer deepens low frequencies and brightens
highs by correcting for time differences in the travel of high vs. low
frequencies in reaching the human ear.

I was wondering.... since the Sonic Maximizer is not only popular to be
used in instrument rigs, but also for P.A. systems and in mix chains
for recording studios, would there be any detrimental effects if I were
to be using the Sonic Maximizer in my guitar rig while playing through
a P.A. or recording studio that is also using one for the entire mix?


Nope.

Check out the archives for a detailed description. You can go to the Patent
server on the web too and read as to exactly what it does, which involves a
frequency dependent phase shifting without any alteration in amplitude /
levels across the entire spectrum. The original design was intended to be
used for optimizing and linearizing phase response and frequency response
with regard to driving a typical moving coil loudspeaker, which is largely
an inductive load in which the impedance changes considerably as to
frequency (note that phase and frequency response are subject to non
linearities when driving an inductive load with a typical solid state
amplifier, even if response is perfect when driving a resistive load). The
patent indicates the use of a small reference inductor used to simulate the
impedance of a typical speaker. The end product was never sold according to
the original purpose, but instead for it's subjective and pleasing effect,
primarily with regard to how it subjectively changes low end response and
'clarity'.

Schuy

[Skler]

http://groups-beta.google.com/group/...d/thread/f7029
ed0150f7042/81ba95045f2cca5a?lnk=st&q=BBE+sonic+maximizer+pate nt&rnum=2#81ba
95045f2cca5a

[Skler]

http://www.delphion.com/

"Here's the patent number for the BBE Sonic Maximizer:
4,482,866

Here's the patent number for the Aphex Aural Exciter:
4,150,253


Please note that neither of these documents will refer to the "Exciter"
or
the "Maximizer" as these are merely names that were used for marketing
purposes. The patented design for the BBE is referred to a "reference
load
amplifier correction system." The Aphex patent is referenced as "signal


distortion circuit and method of use."


BBE Sonic Maximizer:
"A system which corrects for adverse characteristics such as reactance,
inertia and resonances of a power amplifier driven load such as a
speaker or
multiple speaker system. Program voltage is applied to a reference load
which has electrical characteristics that simulate characteristics of
the
reference load, and the response of the reference load to the program is


used to developa correction voltage signal for the driven load. The
program and the
correction voltage signal are simultaneously applied to the power
amplifier
to simultaneously reproduce the program and correct for the adverse
characteristics of the load."


There's a marvelously written text that follows, which provides a
comprehensive explanation.


Have fun!


Schuyler "

[Paul Stamler]

"Ty Ford" wrote in message
...
I believe Aural Exciters were introduced before Linda Ronstadt emerged
as a
solo artist, but I might be wrong. The folk from Aphex have also said
that
the Aural Exciter was invented when the designer accidentally mis-wired
a
Dynaco Mark III power amplifier kit and was wowed by the sound.
Occasionally
they say it was a Dynaco preamp.

My guess is that all of these stories are hogwash.

Peace,
Paul


I got my version from Marvin Caesar. Aphex owner.

The other versions came from interviews with whoever invented the Aphex. If
Caesar invented it, then that's who the interviews were with. All involved
accidental miswiring of a Dynaco. This came from the stories touting this
new wonder when it was first introduced.

Peace,
Paul

[GregS]

In article , "Skler" wrote:

"Ludwig77" wrote in message
ups.com...
I have a BBE Sonic Maximizer that I use in my guitar rig.

As I understand it, the Maximizer deepens low frequencies and brightens
highs by correcting for time differences in the travel of high vs. low
frequencies in reaching the human ear.

I was wondering.... since the Sonic Maximizer is not only popular to be
used in instrument rigs, but also for P.A. systems and in mix chains
for recording studios, would there be any detrimental effects if I were
to be using the Sonic Maximizer in my guitar rig while playing through
a P.A. or recording studio that is also using one for the entire mix?


Nope.

Check out the archives for a detailed description. You can go to the Patent
server on the web too and read as to exactly what it does, which involves a
frequency dependent phase shifting without any alteration in amplitude /
levels across the entire spectrum. The original design was intended to be
used for optimizing and linearizing phase response and frequency response
with regard to driving a typical moving coil loudspeaker, which is largely
an inductive load in which the impedance changes considerably as to
frequency (note that phase and frequency response are subject to non
linearities when driving an inductive load with a typical solid state
amplifier, even if response is perfect when driving a resistive load). The
patent indicates the use of a small reference inductor used to simulate the
impedance of a typical speaker. The end product was never sold according to
the original purpose, but instead for it's subjective and pleasing effect,
primarily with regard to how it subjectively changes low end response and
'clarity'.

The end result is some change in phases which probably has little to do with
the end result of the many scenarios in the many setups which it might be used.


greg

[Ty Ford]

On Thu, 9 Nov 2006 00:27:35 -0500, Paul Stamler wrote
(in article ):

"Ty Ford" wrote in message
...
I believe Aural Exciters were introduced before Linda Ronstadt emerged
as a
solo artist, but I might be wrong. The folk from Aphex have also said
that
the Aural Exciter was invented when the designer accidentally mis-wired
a
Dynaco Mark III power amplifier kit and was wowed by the sound.
Occasionally
they say it was a Dynaco preamp.

My guess is that all of these stories are hogwash.

Peace,
Paul


I got my version from Marvin Caesar. Aphex owner.

The other versions came from interviews with whoever invented the Aphex. If
Caesar invented it, then that's who the interviews were with. All involved
accidental miswiring of a Dynaco. This came from the stories touting this
new wonder when it was first introduced.

Peace,
Paul



Fascinating. Never heard that story. I'll reach out to Marvin.

Ty

-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

[Ty Ford]

On Thu, 9 Nov 2006 10:18:30 -0500, Ty Ford wrote
(in article ):

On Thu, 9 Nov 2006 00:27:35 -0500, Paul Stamler wrote
(in article ):

"Ty Ford" wrote in message
...
I believe Aural Exciters were introduced before Linda Ronstadt emerged
as a
solo artist, but I might be wrong. The folk from Aphex have also said
that
the Aural Exciter was invented when the designer accidentally mis-wired
a
Dynaco Mark III power amplifier kit and was wowed by the sound.
Occasionally
they say it was a Dynaco preamp.

My guess is that all of these stories are hogwash.

Peace,
Paul


I got my version from Marvin Caesar. Aphex owner.

The other versions came from interviews with whoever invented the Aphex. If
Caesar invented it, then that's who the interviews were with. All involved
accidental miswiring of a Dynaco. This came from the stories touting this
new wonder when it was first introduced.

Peace,
Paul



Fascinating. Never heard that story. I'll reach out to Marvin.

Ty

-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

From marvin Caesar, with regards,

Hi Ty,
I was not around when the Aural Exciter was invented. The story I heard was
that it was a Dynaco preamplifer that had one side wired properly, the other
side reverse.
As for the Aural Exciter pre-dating Linda Ronstadt, Peter Asher heard the
Aural Exciter on the piano on the Paul McCartney and Wings Tour in 1976, so
that was actually the first big commercial use of it. Hasten Down the Wind
did have a liner note mentioning the Aural Exciter and Curt Knoppel, inventor
of the Aural Exciter.
Another album preceding Hasten.. was produced using the Aural Exciter. It was
Bill Horowitz "Lies, Lies, Lies" featuring the hit "If I had a friend like
Rosemay Woods". How´s that for some history!
Best regards,
Marvin



-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

[Lorin David Schultz]

leftofthedial wrote:

I lost a client job once because I refused to patch the clients
sonic maximizer into my signal chain.


I recently had a discussion with my daughter about client relations.
Prominent in the conversation was the phrase, "No problem, we can do
that, but are you sure you want us to?"

--
"It CAN'T be too loud... some of the red lights aren't even on yet!"
- Lorin David Schultz
in the control room
making even bad news sound good

[Paul Stamler]

"Ty Ford" wrote in message
. ..
From marvin Caesar, with regards,

Hi Ty,
I was not around when the Aural Exciter was invented. The story I heard
was
that it was a Dynaco preamplifer that had one side wired properly, the
other
side reverse.
As for the Aural Exciter pre-dating Linda Ronstadt, Peter Asher heard the
Aural Exciter on the piano on the Paul McCartney and Wings Tour in 1976,
so
that was actually the first big commercial use of it. Hasten Down the Wind
did have a liner note mentioning the Aural Exciter and Curt Knoppel,
inventor
of the Aural Exciter.
Another album preceding Hasten.. was produced using the Aural Exciter. It
was
Bill Horowitz "Lies, Lies, Lies" featuring the hit "If I had a friend like
Rosemay Woods". How´s that for some history!

What's scary is that I remember that last song.

I'd be most interested to hear how that Dyna preamp was wired in reverse.
It's an unbalanced circuit, so it wouldn't be easy, unless "in reverse"
means that the input jack connected to the output of the circuit and vice
versa.

Peace,
Paul

[Agent 86]

On Mon, 06 Nov 2006 11:55:14 -0800, Ludwig77 wrote:

I was wondering.... since the Sonic Maximizer is not only popular to be
used in instrument rigs, but also for P.A. systems and in mix chains
for recording studios,

Wow, you learn something new everyday around here. MXL603s are useless
for drum overheads. ART is a really good toob preamp for the money. And
Suck Maximizers are popular for PAs and studios.

That's what I LOVE about RAP.

[Agent 86]

On Tue, 07 Nov 2006 08:02:28 -0800, Ludwig77 wrote:


My dad even raved about it being used in his Pedal Steel Guitar rig,
and believe me he is going for the squeaky clean tones as opposed to
the Randolph Family overdrive sound).

OOOOOOOOOOhhhhhhhhhhhhhh!

Just the though of that makes my teeth hurt!

[Romeo Rondeau]

Agent 86 wrote:
On Tue, 07 Nov 2006 08:02:28 -0800, Ludwig77 wrote:

My dad even raved about it being used in his Pedal Steel Guitar rig,
and believe me he is going for the squeaky clean tones as opposed to
the Randolph Family overdrive sound).

OOOOOOOOOOhhhhhhhhhhhhhh!

Just the though of that makes my teeth hurt!


The unit would work much better if the controls couldn't be turned up
all the way :-)

[Agent 86]

On Sat, 11 Nov 2006 00:00:12 +0000, Romeo Rondeau wrote:

Agent 86 wrote:
On Tue, 07 Nov 2006 08:02:28 -0800, Ludwig77 wrote:

My dad even raved about it being used in his Pedal Steel Guitar rig,
and believe me he is going for the squeaky clean tones as opposed to
the Randolph Family overdrive sound).

OOOOOOOOOOhhhhhhhhhhhhhh!

Just the though of that makes my teeth hurt!


The unit would work much better if the controls couldn't be turned up
all the way :-)

Which unit? The BBE or the pedal steel?

[Skler]

The end result is some change in phases which probably has little to do
with
the end result of the many scenarios in the many setups which it might be
used.


greg


Changing the phase response in a particular fashion as to the frequency is
*all* that it does. How that affects subjective performance / effect has a
to do with how the BBE interacts with the load and the fact that transducers
are inductive loads with a highly predictable non linear impedance curve. I
was thinking... it might be interesting to use a BBE with a pair of
electrostatic speakers or headphones for example and then listen to the
difference in effect by making a side by side comparison with a typical
moving coil loudspeaker. :-) The BBE is a pretty interesting and fun thing
from both a technical and sonic standpoint, me thinks. It's also amazing to
me how long the device has been in popular use. Someday, if moving coil
loudspeakers are no longer in popular use though, replaced by some other
kind of transducer that isn't inductive, then someone will probably invent a
black box that simulates the non-linear load impedance problem that the
"sonic maximizer" was originally intended to cure. :-)


Skler

[Paul Stamler]

"Skler" wrote in message
...
The end result is some change in phases which probably has little to do
with
the end result of the many scenarios in the many setups which it might
be
used.


Changing the phase response in a particular fashion as to the frequency is
*all* that it does. How that affects subjective performance / effect has
a
to do with how the BBE interacts with the load and the fact that
transducers
are inductive loads with a highly predictable non linear impedance curve.

How the BBE interacts with the load? Correct me if I'm wrong, but I always
thought the BBE was a line-level device with plenty of buffering in and out.
So it shouldn't interact appreciably with the load at all.

Peace,
Paul

[Skler]

Changing the phase response in a particular fashion as to the frequency
is
*all* that it does. How that affects subjective performance / effect
has
a
to do with how the BBE interacts with the load and the fact that
transducers
are inductive loads with a highly predictable non linear impedance
curve.

How the BBE interacts with the load? Correct me if I'm wrong, but I always
thought the BBE was a line-level device with plenty of buffering in and
out.
So it shouldn't interact appreciably with the load at all.

Peace,
Paul



You're right in that it isn't directly coupled to the load. But it does
interact with the load in the same sense that any signal interacts with the
load. Sure, it's the power amp that's actually driving the load, but all
*signals* that pass through a power amp affect that interaction as well; in
fact it's the essential part of that interaction because in the end, it's
what we want to hear! My explanations are probably not very good because I
just touch on highlights and leave out tons of background stuff. Let me see
if I can dig up the patent (at the bottom of a pile of papers among many
piles!) and post the explanation offered by the guy who actually invented
the BBE. That might be best.

Okay... I'm going off into the landfill of papers in the other room. Wish me
luck...


(10 minutes later...)

Okay; naturally it was in the last place that I looked. :-\

Here are some excerpts (transcribed as I don't have them in digital format
and I'm not scanning it for the moment)

"Patent number: 4,482,866"
"Inventor: Robert C. Crooks"
"Assignee: Barcus Berry Inc."

"Abstract
A system which corrects for adverse characteristics such as reactance,
inertia and resonances of a power amplifier driven load such as a speaker or
multiple speaker system. Program voltage is applied to a reference load
which has electrical characteristics that simulate characteristics of the
driven load, and the response of the reference load to the program is used
to develop a correction voltage signal for the driven load. The program and
the correction voltage signal are simultaneously applied to the power
amplifier to simultaneously reproduce the program and correct for the
adverse characteristics of the load."

And later in the patent:

"... it is a general object of the present invention to provide a system
which substantially and accurately corrects for adverse characteristics of
an amplifier driven load that would otherwise cause the output of the load
to deviate from the applied program, such adverse characteristics including
but not being limited to electrical reactance, inertia, resonances, and the
like.
Another general object of the invention is to provide an amplifier load
correction system which has particular utility in audio systems,
substantially completely correcting for the normally seriously distorting
effects of inductive reactance, inertial lag and overshoot, and speaker
compliance and associated open air cone resonance."

For further, go to the patent server and down load it! It's only a few
bucks.

This statement is followed by a drawing that shows an op amp input buffer
with the phase shift circuit, including reference inductor, which is then
followed by a power amplifier and a conventional loudspeaker. There are a
number of variations of the circuit illustrated for clarity.

Okay, I sit corrected on this one, now that I have reviewed the actual
patent again. There is a plot that shows the impedance and phase
characteristics of a typical loudspeaker, then another plot that actually
shows amplitude correction effected by the phase shift circuit (therein
mentioned)! So I didn't remember that part correctly; sorry. :-)

One of the ways the device is referred to in the patent is that of a
"reference load correction system", which is a pretty apt description, I
think.

Another thing that occurred to me, is that the way the BBE is intended to
work might not be appropriate, considering the way many loudspeakers are
bundled in 2 or 3 way configurations, and with passive LC crossover
networks. I think the invention was intended to correct for individual
speakers, not 2 or 3 way networks... Oh well. The BBE is still an
interesting and subjectively pleasing effect in many situations. I think
it's pretty neat@!

Schuy

[Scott Dorsey]

Skler wrote:

You're right in that it isn't directly coupled to the load. But it does
interact with the load in the same sense that any signal interacts with the
load. Sure, it's the power amp that's actually driving the load, but all
*signals* that pass through a power amp affect that interaction as well; in
fact it's the essential part of that interaction because in the end, it's
what we want to hear!

This doesn't really make any sense at all. This is a buffered device.
Source and load impedances should not matter very much at all. These
are all issues that were conquered in the 1930s.

My explanations are probably not very good because I
just touch on highlights and leave out tons of background stuff. Let me see
if I can dig up the patent (at the bottom of a pile of papers among many
piles!) and post the explanation offered by the guy who actually invented
the BBE. That might be best.

The problem is that the explanation offered doesn't explain what the thing
does. Group delay is surprisingly inaudible; the recent paper by Vanderkooy
shows that pretty well. The effect of the BBE cannot be explained in terms
of phase shift because if you use a box that actually DOES only provide
phase shift (like the Little Labs IBP), it has really only minimal sonic
effect.

Also, of course, if you run a spectrum on the output of the BBE box, you
will find lots of high order even harmonic products. Try it and see.

"... it is a general object of the present invention to provide a system
which substantially and accurately corrects for adverse characteristics of
an amplifier driven load that would otherwise cause the output of the load
to deviate from the applied program, such adverse characteristics including
but not being limited to electrical reactance, inertia, resonances, and the
like.
Another general object of the invention is to provide an amplifier load
correction system which has particular utility in audio systems,
substantially completely correcting for the normally seriously distorting
effects of inductive reactance, inertial lag and overshoot, and speaker
compliance and associated open air cone resonance."

For further, go to the patent server and down load it! It's only a few
bucks.

Yes, and this may well be what Mr. Crooks had in mind when he built the
device. But it's not what the device actually DOES. Measure it and see.

One of the ways the device is referred to in the patent is that of a
"reference load correction system", which is a pretty apt description, I
think.

Right, this has nothing to do with actual output loading.

Another thing that occurred to me, is that the way the BBE is intended to
work might not be appropriate, considering the way many loudspeakers are
bundled in 2 or 3 way configurations, and with passive LC crossover
networks. I think the invention was intended to correct for individual
speakers, not 2 or 3 way networks... Oh well. The BBE is still an
interesting and subjectively pleasing effect in many situations. I think
it's pretty neat@!

Try the Little Labs IBP some time. It actually does what the BBE box claims
to do. It's not very useful for compensating for speaker issues, but it can
be wonderful for dealing with comb filtering from multiple microphone feeds.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Skler]

Yeah; one will not hear group delay as a frequency dependent effect, because
it's just shifting the speakers response to a given signal in time. If you
have frequency dependent phase shift however, and with an inductive load at
the end of the signal chain, you will hear the effect, at least according to
the BBE claims.

This is sort of differnt topic, but you've touched on something that I find
curious that there are often discussion about delay and phase in which these
two factors are considered as unrelated, even though phase is actually
frequency dependent expression of time and can be expressed mathematically.

Also, of course, if you run a spectrum on the output of the BBE box, you
will find lots of high order even harmonic products. Try it and see.

To me, the most enjoyable subjective thing to try with the BBE is to use
stereo program material and then add the effect & AB it with the unaffected
program. Bass is particularly affected, seeming more prominent
subjectively, but it's more than a simple increase in bass amplitude, which
to me is very interesting. If all the BBE were doing was boosting low end,
then it might sound essentially like some kind of equalizer.


Yes, and this may well be what Mr. Crooks had in mind when he built the
device. But it's not what the device actually DOES. Measure it and see.


What did you measure?


One of the ways the device is referred to in the patent is that of a
"reference load correction system", which is a pretty apt description, I
think.

Right, this has nothing to do with actual output loading.


What if one measured response across a typical loudspeaker, say frequency vs
amplitude with & then without the BBE, and then measured the response with
no load at all... What would these measurements show?



Try the Little Labs IBP some time. It actually does what the BBE box
claims
to do. It's not very useful for compensating for speaker issues, but it
can
be wonderful for dealing with comb filtering from multiple microphone
feeds.


Sound interesting.... :-)


Schuy

[Skler]

To me, the most enjoyable subjective thing to try with the BBE is to use
stereo program material and then add the effect & AB it with the
unaffected
program. Bass is particularly affected, seeming more prominent
subjectively, but it's more than a simple increase in bass amplitude,
which
to me is very interesting. If all the BBE were doing was boosting low end,
then it might sound essentially like ** some kind of equalizer**.


Y'know, maybe I should have said, "any old equalizer" or "any other
equalizer"?

The BBE certainly does have it's own characteristic sound.

:-)

Skler

[Scott Dorsey]

Skler wrote:
Yeah; one will not hear group delay as a frequency dependent effect, because
it's just shifting the speakers response to a given signal in time.

No, it's not. That's fixed delay, not group delay.

If you
have frequency dependent phase shift however, and with an inductive load at
the end of the signal chain, you will hear the effect, at least according to
the BBE claims.

Group delay IS frequency dependant phase shift, and it's really not very
audible. Try the IBP for yourself if you don't believe Vanderkooy's paper.

To me, the most enjoyable subjective thing to try with the BBE is to use
stereo program material and then add the effect & AB it with the unaffected
program. Bass is particularly affected, seeming more prominent
subjectively, but it's more than a simple increase in bass amplitude, which
to me is very interesting. If all the BBE were doing was boosting low end,
then it might sound essentially like some kind of equalizer.

Right, what is happening is that you are getting harmonics of the low frequency
material mixed into the output. This makes the low end sound more defined.

Yes, and this may well be what Mr. Crooks had in mind when he built the
device. But it's not what the device actually DOES. Measure it and see.

What did you measure?

I ran a spectrum on the thing. I discussed this here around 1992 and showed
a bunch of raw data on the output spectrum, given constant-amplitude tone
sources as input.

What if one measured response across a typical loudspeaker, say frequency vs
amplitude with & then without the BBE, and then measured the response with
no load at all... What would these measurements show?

Umm... the BBE is not connected to the speakers.... the speakers are not
presenting a load to the BBE box. The speakers are presenting a load to
the amplifier. What these measurements would show is how the amplifier
output changed with load.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Bob Cain]

Scott Dorsey wrote:
Skler wrote:
Yeah; one will not hear group delay as a frequency dependent effect, because
it's just shifting the speakers response to a given signal in time.

No, it's not. That's fixed delay, not group delay.

Fixed delay is constant group delay; phase shift being a linear
function of frequency.

When I measured the BBE plugin a few years ago, which I know isn't the
same thing as the box, I found that it was basically a Baxendall three
band tone control implemented such that the group delay decreases with
increasing frequency. This ostensibly brings the transients out
earlier than the LF which follows them and to my ear this did subtly
increase "clarity" without changing frequency response magnitude.

With the plugin I could find no evidence of the exciter behavior. It
was quite linear. I know, apples and oranges, but a data point at any
rate.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Ron Capik]

Scott Dorsey wrote:

...snip...

Group delay IS frequency dependant phase shift, and it's really not very
audible. Try the IBP for yourself if you don't believe Vanderkooy's paper.


Or if (like most of us) you don't have an IBP handy, you can try this
experiment:
Take a sound file, add some EQ, then reverse the file and subtract
the EQ, then re-reverse so all's going in the right direction. The file
will now have group delay and no amplitude change.
Then A/B the files.
For even more fun take a stereo file, reverse one channel then
do the above EQ thing and you will have a file with group delays
in opposite directions. In this case you should notice a shift in the
stereo image.

[ Note: Some digital EQs are not symmetric so you could introduce
artifacts that may cloud the results. ]


Later...

Ron Capik
--

[exp(j*pi/2)]

Bob Cain wrote:
I know, apples and oranges, but a data point at any
rate.
Bob

You may know apples and oranges, but you don't know **** from shinola.





"Things should be described as simply as possible, but no simpler."
A. Einstein

An idiotic quote which you have fabricated, which you falsely attribute
to Einstein, and which has about as much depth as **** on a flat rock.

[Skler]

Hey,


Just for fun, how would you define the difference between group delay and
phase shift?


And would you say that group delay can be audible?


I think you said in your post that phase non-linearities are generally not
preceived in audio?


Wouldn't it depend on how much phase shift one was dealing with?




Schuy

[Skler]

"Bob Cain" wrote in message
...
Scott Dorsey wrote:
Skler wrote:
Yeah; one will not hear group delay as a frequency dependent effect,
because
it's just shifting the speakers response to a given signal in time.

No, it's not. That's fixed delay, not group delay.

Fixed delay is constant group delay; phase shift being a linear
function of frequency.

I'm interested in clarifying this part.

Just plain old delay is constant as to frequency, I know that, and also that
phase angle can expressed as a frequency dependent measure of time, e.g.
Time (in seconds) = Phase angle / Frequency(360). Is there an equation for
group delay?

I guess I'll do some reading... Here's an interesting URL I found on my
first search: http://www.trueaudio.com/post_010.htm Should be fun. :-)
This article mentions the idea of a psychoacoustic threshold at which group
delay becomes audible. According to
http://www.technick.net/public/code/...guide_edft_013, it
sounds like group delay and phase response are different expressions of the
same phenomenon: Frequency dependent delay, although some definitions
mention "packets" of information or the delay response within the pass band
of a filter. One article mentioned that group delay was the relationship
between the initial over-all response of a filter, for example, and it's
peak response.


When I measured the BBE plugin a few years ago, which I know isn't the
same thing as the box, I found that it was basically a Baxendall three
band tone control implemented such that the group delay decreases with
increasing frequency. This ostensibly brings the transients out
earlier than the LF which follows them and to my ear this did subtly
increase "clarity" without changing frequency response magnitude.

That's what I suspected was going on, at least in terms of subjectively
altered low end for example, but without magnitude change.

I have the BBE plug in too. I think they got the transfer function pretty
close in terms of how it sounds as compared to the analog box.

With the plugin I could find no evidence of the exciter behavior. It
was quite linear. I know, apples and oranges, but a data point at any
rate.

Schuy