Pandora's Boxes
To those of you who thought I was dead and buried-sorry to
burst your bubble. To those of you who wish I were dead and
buried-sorry but you'll have to put up with me for a while longer.
Ha ha. Yes, I have been away from playing an active role in
the audio industry for a number of years but that doesn't mean
that I've been out of touch. Not by a long shot. As a matter
of fact, I've used this time-span to become even more in tune
with various aspects of the arts and sciences of audio mainly
because I haven't had the burden of running a company. To be
sure, I'm probably going to tick off a lot of people by ranting
and raving but hopefully this will have a positive effect rather
than the opposite. The reason for this is very simple. I'm not
going to live long enough to be able to see all of my ideas
and concepts happen. I don't have enough time and I sure don't
have enough money. So my advice to those dilettantes out there
is simple-don't look a gift horse in the mouth. Several of my
friends have convinced me (finally) that I should make my ideas
known so they don't get buried with me. I have resisted for
many years but finally, I've decided to give in.
Lest any of you think that I'm being egocentric or narcissistical,
I can assure you that my 40 some years of experience gives me
some expertise in matters audio and I'm willing to share this
insight-free of charge-at least here in these pages. The information
presented here is meant to be informative if not somewhat dogmatic.
Certain facts should be self-evident however this is not always
the case.
Chapter
1
Human Hearing: How Do We Really Hear?
First of all, we hear in stereo but only because we have two
ears and there is a time/phase difference between our ears.
This time difference is first used to perceive DIRECTION. It
is absolutely mandatory for us to know WHERE a sound comes from.
Next in the chain is amplitude or perceived loudness. This tells
us basically how close or how far away a sound originates from.
This is also aided by secondary reflections. Unfortunately,
when we are beyond the zone of parallax, our directionality
sense can be lost. Finally, after the direction and the distance
comes RECOGNITION. These are the three basic elements in human
hearing. The third one, recognition, is however, a paradox.
For example, if one were born and raised in a cave for the first
20 years of life with absolutely zero exposure to the outside
world, then all sounds no matter what would be totally foreign
and unrecognizable. Another example of this would be if one
of your high school pals, whom you haven't spoken to in over
30 years were to suddenly call you on the phone and play the
guess who this is game, you probably wouldn't know who
it is. But as you keep talking, little tinges of recognition
start creeping into your brain although you still can't place
the person. Finally, the person tells you who it is and all
of a sudden total memories take over and flood your brain. Three
days later, this same person again calls you and you instantaneously
recognize the voice.
What this all boils down to is memory retention. And the same
relative phenomenon goes for sight as well. From the day you
are born, your brain automatically stores all sound and sight
in its memory banks. This is what recognition is all about.
This is probably why everyone's perception of things
is slightly different than the next person. We may receive quite
similar stimuli however, our perceptions and interpretations
may be totally different. Also, due to the physical differences
and character of our eyes and ear canals, our perceptions can
be of a different nature for the same set of events. This is
why some people claim to hear certain things while others can't.
This is especially bad when we are dealing with a sound system
where we DON'T have our vision working for us. Imagine yourself
in a club or at a concert, etc. where the extraneous noises
consist of clinking glasses, rustling clothing, air conditioners,
sneezing, talking, coughing, etc. Basically, due to the human
cocktail party effect we can tune out most of this interference
and hone in on exactly what we want to concentrate on. Can you
picture yourself trying to do this at home where your wife or
mother, etc. is doing the dishes with all of the clinking and
you practically go nuts because of the noise interference? This
is because your ears are working MUCH harder than normal because
you don't have your vision. This is probably why blind people
are accredited with having much more sensitive hearing than
normal people. What does this tell you? Pure and simple by default,
you are way too over-critical because of the lack of other senses.
Plain and simple: you are not in the real world. You have created
a fantasy world of sound, and any imperfections are going to
be magnified all out of proportion to reality. It's bad enough
that the entire concept of sound as we know it is monumentally
flawed, yet our senses actually make things worse. It is absolutely
astonishing that we can get any enjoyment at all out of our
stereo systems.
One last little tidbit, if I may. It's Super Bowl Sunday. Sometime
before game time, you turn on your great big super projection
screen TV and instantly, a huge puff of smoke arises and the
whole thing goes dead. Do you think that you're going to find
a repairman under these circumstances on this day? Not a chance.
So, you grab maybe your wife's little 9 inch or so black and
white TV that she lugs around the house while doing housework.
This TV has this puny little screen and a puny little 2 inch
speaker that sounds absolutely terrible. But, when it comes
game time, your ACCEPTANCE LEVEL goes to 100% because it's live
and it's happening right now. The awful quality factor is totally
disregarded under the circumstances. Nice to have both eyes
and ears going for us. Enough Said.
The problem with sound systems is very simple. There is no scientific
way that true holographic presentation is ever going to happen.
It just can't be for a lot of reasons of which I will delve
into as we get on with this series. Can we get closer to the
real thing? Absolutely! Do I have some of these answers?
You bet. But to be truthful and honest, I don't think we will
ever get past about 50% acceptance level. At least not in our
lifetime. Besides, as long as the wife claims the living
room as her habitat, we will always be in a dilemma.
Back to Contents
Chapter
2
The Stereo Equation: Correct Format, Or Impossible Science?
To be sure, the stereo equation, or formula if you wish, is
NOT made up of just L(left) & R(right). There are a multitude
of directional paths, or vectors, that make up the entire panorama
across the sound-stage. In addition, the worst thing about this
situation is that there is NO center, which is the MOST important
thing. If you think about it, almost all of the important information
generally clusters toward the center. In the present format,
the only way that center information is obtained is by reproducing
half of the power, -3db, in each speaker. In all cases, any
information must algebraically add up to 100% of the representative
power in an acoustic sense. It is therefore, very obvious to
see that even small body movements can cause large shifts of
imaging. That is where the phrase sweet spot or “forceps
on the head comes from. This of course is absolutely unacceptable
from my point of view. That's why I listen predominately to
headphones.
By default, the stereo formula must also contain a cross-coupled
error component in order to work at all. This is unfortunately,
the Achilles heel of the concept. Recording engineers have been
battling this disease from day one. From the recording side
of things, it is a losing battle because for the most part,
there is no solution. And to think that the industry is now
going to try to move towards Multi-channel recording. Give me
a break. They can't even get 2 channel correct. I see another
debacle coming just like the Quad-sound fiasco of the 70's.
Of course there are two parts to this puzzle. One is the alignment
vectors and the other is presence” of which I will address in
a later chapter. For the moment, all you as a consumer can do
is to (1), elevate your speakers off the floor, preferably above
ear level and (2) angle (toe in) them inwards so that the image
crosses somewhat in front of your head (about 1 foot). Also,
subwoofers should always be located to maximize the wavelength,
preferably in the corner facing diagonally. There is a solution
coming for the vector problem. It's called the TRINAURAL
PROCESSOR. It will be available shortly and I'm sure that
your audio life will be changed forever.
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Chapter
3
Loudspeakers & Acoustics: Why The Whole Thing Sucks
The problem with most loudspeaker designers is that they seem
to want to reside totally in the scientific arena and they are
absolutely totally ignorant of the real world necessities
regarding acoustics and human hearing. When I go to trade shows,
etc., I usually avoid at all costs trying to listen to speakers.
Usually, my ears are raped over and over again and I have long
since given up trying to explain why loudspeakers as we currently
know them cannot possibly provide realistic sound. My words
fall on deaf ears, pun intended. Once in a great while,
I find something worthwhile but this is exceedingly rare. A
few years ago I was invited into Keith Johnson's private showing
at CES and for me, who hates most all speakers, was astounded
with what I heard. What I want to know is, when are these things
going to be on the market. Also, I heard recently, a pair of
speakers from John Dunlevy which were exceptionally good. And
they were not his top of the line either. When in doubt, one
can always fall back on the venerable Quad ELS-63's if you can
live with the acoustic limitations.
This section is not meant to be a recommendation platform for
speaker designers so let me stop here. There are others of course,
such as Arnie Nudell's recent mid-priced speakers which show
promise as well as the full set of Maggies-enough said. I have
often stated that the application science and the math behind
loudspeaker design is basically flawed. This is so because Stereo
DOES NOT EXIST IN THE REAL WORLD. But since we cannot have any
kind of MONO reproduction system, there is obviously a horrendous
conflict going on. On the one hand, speaker designers try to
use the science in creating what they perceive as the perfect
MONO reproducer. But clearly this makes absolutely no sense
if our environment demands a minimum of two reproducers. I have
repeatedly told people that things like flat frequency response,
low distortion, etc. are NOT of first order importance. They
are only of second order importance. I once heard a loudspeaker
system (to be unnamed) which produced virtually perfect square
waves, had incredibly low distortion, etc. It was absolutely
one of the worst things I ever heard and I wanted to run screaming
out of the room. When I tried to explain to the designer what
I was talking about, he was totally miffed and dumbfounded and
just didn't get it. The ego unfortunately protects our belief
system(s) regardless of whether they are right or wrong.
Regarding acoustics, things of first order importance are time
of arrival of all frequencies between approximately 200Hz and
20,000Hz. In addition, the radiation angle must also be constant
between these same frequencies and in my opinion should lie
in the area of 1 ˝ radians, or about 80 degrees. When and only
when these two things are accomplished (no mean feat, by the
way) then frequency response, distortion, etc. can be worked
on. Why are these things necessary? Understand that in ANY musical
performance whether in a club, a theater, or at a concert, etc.
all PRIMARY sound(s) come from the front. THERE IS NO REAR.
Of course, reflections will play a part in the acoustic environment
but, these are only after the fact. Creating a decent field
in your living room is not an easy task. But bear the following
in mind. The source is generally as good as you get to start
with. The other weak links in the chain are the Stereo Format
itself (discussed elsewhere), the room, and the speakers. Your
electronics really only play a minor role in the greater scheme
of things. Obviously, there is not a whole lot that one can
do to their listening area other than absorption at high frequencies
and possibly woofer location to smooth over the eigentones at
low frequencies.
One final thought is in order. Dick Sequerra and Keith Johnson,
where are you. In the last several years I have only heard three
loudspeakers that came close to providing what I believe is
a true sense of quasi-reality. That is to say that I
came very close to being immersed into the musical experience
as if I were almost there. The first was recently when I heard
John Dunlevy's latest mid-priced speaker. The second was a few
years ago at a CES show where Dick Sequerra had his second version
of the larger metronomes playing. I must admit that these were
absolutely the finest speakers that I ever experienced in my
life to that date. Sadly, he never pursued manufacturing them:
the world's loss. Finally, two or three years ago, Keith Johnson
invited both myself and Bascom King into his private listening
room next to his display room. I have to tell you all that this
was an experience to beat all. Nothing I have ever heard on
this planet comes as close to reality as what I heard that day.
Of course, he was playing his own recordings but, it still was
uncanny. Keith, are you listening (no pun intended).
Back to Contents
Chapter
4
Circuit Design: True Science, Or Pure Gobbledygook?
Circuit design like all other aspects of life has evolved in
staggering proportions over the years. I am of course talking
about solid state and not tubes. Truthfully, there isn't a whole
lot that can be done with tubes that hasn't already been done.
I know I'm going to take some heat for that statement but the
facts speak for themselves. Solid state circuitry on the other
hand still has a long way to go. Ironically, for the most part,
new solid state circuit designs came to a screeching halt about
18 years ago, just when I got out of the business. Is this an
arrogant statement or what. Criticize me if you must but, I
do believe that I know what I'm talking about. There has been
absolutely nothing new and shocking since I did the full differential-full
complementary circuits at Sumo. And in a lot of ways, the industry
has actually gone backwards regarding circuit design. The truth
of the matter is very simple in that everyone CANNOT be king
of the mountain. When I left the design arena, everything seemed
to come to a grinding halt. Sure, the pricing structure of today's
products has gone astronomical. And if that's not bad enough,
you are not getting anywhere near as much for your money. What
I'm talking about is preamps with NO phono stages or tone controls
or filters or other necessary functions. And you are forced
to pay megabucks for these insults. I think it is criminal.
I will never make a preamp without these absolutely necessary
features. The LP is NOT dead. And CD's still have a mighty long
way to go before they even come close to the musicality of records.
When I conceived the full complementary circuitry in 1972 I
felt at the time that this was the final answer to the solid
state jigsaw puzzle. I was only half right. Yes the philosophy
is correct however, the implementation is what really counts.
It has taken me almost 30 years to really understand the relationships
involved in full complementary circuits. Some things that at
first glance seem naturally right and correct are found later
to be not so right. For example, splitting the positive and
negative halves of the signal into two separate amplifying chains
and then trying to merge them back together at the output stage
raised a can of worms. The reason is simple: the two separate
amplifying chains are NOT complementary. They may be close but-no
cigar. What is needed is a new look at each individual part
of the chain and its respective counterpart. This is a new mode
of thinking about this problem and finally I can say that results
have been achieved. The new Ampzilla2000 is the first amplifier
using this change of philosophy. I'm sure that others will look
at this new style of circuitry and like my previous work, I'm
sure it will be extensively copied. It will be up to me to remain
ahead of the pack. There will be a much more extensive tutorial
on these new concepts at a later date.
Needless to say, the Ampzilla 2000 circuit design is a radical
departure from all previous thinking. First of all, the input
stage itself, while being an integral part of the overall feedback
structure, is nevertheless, a push-pull complementary feedback
structure on its own while being integrated into the main feedback
loop itself. What this does is to aid in correcting some of
the open loop maladies BEFORE they arrive at the output stage
therefore lessening the need for the overall feedback to work
as hard. This is significant because the innards of the
circuit can now be probed and the results are significantly
different than all previous amplifier topologies. What I'm saying
is that now we can go INSIDE the loop and actually measure the
performance of the amplifier as a linear function whereas in
the past, all we saw was the overall correction waveform. More
on this in the white paper to follow. This is of course only
a first step in my new thinking. I firmly believe that today's
circuit designers need to get off their collective duffs
and start thinking about these kinds of theories. Am I to do
all the work for them?
Back to Contents
Chapter
5
FM Technology: Can It Really Be Acceptable?
It should come as no surprise that improvements in FM technology
have been very slow in coming over the decades. Part of this
may be due to the belief on the part of FM design engineers
of why bother when the stations are never going to improve
the quality of their broadcasts. Actually, this is a classic
chicken and egg syndrome. Again, what is needed here is some
new blood or at the very least some new thinking. The first
question to ask is; Is it possible to have any improvements
in the enterprise? The answer is of course, absolutely. But
first, it will never happen until we get rid of the old fuddy-duddys
at the NAB. They are living in the stone age. Secondly, the
FCC is equally to blame because it is of the same mind-set.
Or should I say mindless set. Firstly, I have a patent
on a radically new IF technology that would allow FM reception
to achieve S/N ratios in excess of 100 dB's. Yes you read right.
Also, my new system will produce IN STEREO, a distortion factor
of less than .01%. Yes, you read that right too. In addition,
and I might add without my new system, conventional tuners could
achieve a S/N difference (that is between mono and stereo) of
3-4 dB's, with a little effort. The prevailing philosophy which
has been around since the adoption of FM stereo is that there
must be an automatic S/N penalty of around 20-22 dB's. The truth
is that this is pure hog-wash. It just ain't so. I routinely
achieve a 3-4 Db difference when I upgrade my Charlie's. In
other words, I get around 84 to 86 Db S/N in mono and around
81 to 83 Db in Stereo. It can be done. Yes, there is a secret
to it. But it is achievable.
Getting back to the discussion at hand, there are techniques
that could be easily adopted that would allow stations to maintain
their coverage yet still put mechanisms in place that would
allow TRUE dynamic range to be restored at the receiver end.
As a matter of fact, this wouldn't even require any rules changes
by either the FCC or the NAB. All that would be required would
be that the set manufacturers meet with the stations and broadcast
equipment manufacturers to work out a solution that is so obvious,
that it stares me in the face. Why doesn't anyone else see it.
Well, that question has an obvious answer. Forest and trees,
etc. And as far as where we are headed, with digital broadcasts,
I see a real debacle coming. I can see no way on earth where
the new digital spectrum, which occupies the EXACT SAME SPECTRUM
AS THE CURRENT FM SIGNAL, can be anything but a disaster
waiting to happen. Without the benefit of true multiplexing,
which the new system is NOT, two objects CANNOT occupy the same
space at the same time --- PERIOD. So, we'll have to wait on
this one. But don't be surprised that if all of a sudden one
day, your barely acceptable FM signal turns to pure mush and
garbage. You read it here first.
Back to Contents
Chapter
6
Numbers, Numbers, Numbers: What Fallacies Belie
Over the last 8 decades or so, the most tremendous misunderstanding
in audio measurements has been with us. We have allowed ourselves
to be constantly fooled by techniques that are worthless and
meaningless. They have fooled us into a false sense of reality.
The truth is that distortion measurements as has been the common
practice, are worthless because of misinterpretation. I will
attempt to explain the truth in all of this so you can grasp
a truer and fuller understanding of what the numbers truly mean.
First of all, with present instruments, the measurement of distortion
does not produce anywhere near a correlative result, which would
compare the readings with what we would hear or perceive acoustically.
It is a well known fact that the curve of human hearing is NOT
linear. For example, in order to make a given sound appear twice
as loud, it takes 10 TIMES more amplifier power into the loudspeaker.
To make a sound appear 4 times as loud, it takes 100 TIMES more
amplifier power. To make a sound appear 8 times louder, it takes
1000 TIMES more amplifier power. Therefore, how does this relate
to our distortion measurements? An example is in order. Let
us say that we are testing an amplifier and just for the sake
of argument, this amp is producing 1% distortion at a certain
power level, say 1 watt. That is, the distortion meter is showing
a reading of 1%. This is equivalent to –40dB's. However, this
is where the paradox begins. Under these circumstances, the
1% distortion reading is equivalent to 100 MICROWATTS of power.
This is an equivalent power level which is 10,000 TIMES below
the 1 watt level. Remember that here, we are dealing with the
TRUE distortion product as opposed to just the voltage measurement.
But we know that the hearing ratio of –40dB's is only 16 times.
What this really means is that the TRUE distortion product is
really 6.25% and NOT 1%. In a second example let us say that
the distortion at the aforementioned 1 watt level is measuring
.01% which is considered today to be exceptionally good performance.
The character of the distortion aside, let's limit our discussion
here merely to the numbers. In this case the distortion product
would be –80dB's or a level of 10 NANOWATTS. This is a power
ratio of 100 MILLION TO ONE. You might think that this is insignificant
but hold on. Things are not as they seem. The acoustic difference
of –80dB's is a ratio of 256 to 1. This corresponds to a true
distortion PRODUCT of .39%. This is a far cry from .01% which
is what the distortion meter is telling us. What this boils
down to is this. Our hearing sensitivity is vastly more acute
than most people realize. This may be an answer as to why various
people can claim to hear differences in products that otherwise
might be considered as inaudible. I am of the belief that a
new standard in audio measurements is needed to reflect this
hearing acuteness. Is anyone out there listening?
Back to Contents
Chapter
7
What Digital Revolution? Give My Ears A Break
When I decided to evaluate CD's way back around 1983, I was
not prepared for how bad these things were going to sound. And
I mean BAD. My ears were totally raped. I was very careful in
that I only purchased CD's where I had the record album to compare
with. Granted, that didn't make for a large collection, but
I heard what I (didn't need) heard. It was just plain awful.
Of course, a great deal of this bad sound was due to the aliasing
right at the input to the A/D converters. Obviously there were
virtually no clicks and pops and the S/N ratio was far better
than phono recordings. However, the sound was flat, with hardly
any dimension. Sort of looking at a photo instead of a true
3-dimensional presentation. Also, there was a sterility to the
sound quality making it almost robotic instead of musical. The
lushness that I have always enjoyed was gone. In its place was
a mechanical monster. Things have improved dramatically over
the years however, it AIN'T there yet. Far from it. The overload
problems don't seem to be a problem anymore and of course the
dynamic range is exceptionally good. But the dryness, lack of
depth and overall general blasé' are still there. Since I am
not a digital expert, I can only comment here on what I hear
and for the most part, I'm going to stick with my records. I
only wrote this to put my two cents worth into the forum which
is going to continue for some time to come.
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Chapter
8
Presence: The Real Missing Link
I have saved this tidbit, although it really isn't
a tidbit, for last because it is probably without a doubt the
most difficult situation to solve if it can ever be solved. As
stated many times before, stereo is for the most part an illusion
at best. The real question becomes, how can we improve this illusion
so that it gets closer to reality. In a real world situation,
your ear-brain link needs to do NO work. If it's real, it's real-period.
The further away from reality the more the ear-brain link has
to fill in all of the missing, or should we say incorrect, information.
Obviously, the greater the disparity of information, the harder
it is to achieve this human correction factor.
When I go to a live event, I like to sit right there in front.
This is my preferred listening position. I have however, several
friends who like to sit way back far away from the event. It doesn't
matter that I couldn't do that. That is their preference. Now,
in order to satisfy both situations, how does the recording engineer
set up the mikes? Big dilemma. It becomes painfully obvious that
this is a lose-lose situation. In addition, this problem CANNOT
be solved by the use of the volume control because it is a problem
mostly of time rather than loudness.
The use of processors to create hall effects is for the most part
a joke. The time problems still exist on first arrival information.
There are some very exotic microphone techniques that can be used
to help, but not cure, the problem somewhat. I have yet never
met a recording engineer that wasn't like a prima-Donna in these
matters inasmuch as they aren't interested in outside guidance.
They think they know it all. Why then do most recordings sound
so bad relative to this situation.
There are also other much more effective techniques that could
be used that would dramatically improve this situation. These
other methods would involve a substantial engineering development
program but that shouldn't matter if the end justifies the means.
Again, no interest anywhere. To be sure, there is no amount of
electronic gizmo-ing that will solve this problem because it involves
real time correction. This is a real agonizing situation for me
because I know how to achieve these things and I can assure you
that the results would be absolutely spectacular. But we have
an industry that is mired in a quagmire of 1950's style thinking
and can't seem to get out of the hole. Sure, the quality of components
and devices has been dramatically improved but, so what. Wouldn't
it be nice to have an equal improvement in the reality of the
presentation?
You may all be thinking that I'm talking just a bunch of gibberish
here, but I think that most of you out there no how serious I
am about matters audio. So until the right support situation comes
along with some pockets deeper than mine, we'll all just have
to wait on a hope, a wish, and a prayer, that someday someone
will recognize exactly what I'm saying here and decide to do something
about it.
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James Bongiorno
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