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The Missing Sonic Controls
What would it take to enjoy once again your
favorite music? More money? Greater
technological advancements in the design of CDs,
amplifiers, and loudspeakers? Still the 5-inch
loudspeaker once did provide enjoyment while
playing certain songs. No, the restoration of that
lost enjoyment requires not more money nor even
better technology, but a restoration of lost sonic
control over our listening system, as only by doing
so can we regain the ability to tailor and adjust the
sound, to undo the stark minimalism, to exploit the
technologically advanced stereo equipment
available today, to adapt to the music we want to
hear; in other words, to make the system conform
to our demands, our pleasure, and our enjoyment.
But...wait a minute! What does our enjoyment
have to do with sonic truth? Shouldn’t a stereo
system be like a perfectly clean window giving
unto the Kingdom of Sound? Thus, do we not all
seek the absolutely
true
sound possible, wrinkles
and warts included? Far too many of us do,
unfortunately. Consequently, the prevailing view
today is that a stereo system should be something
like an entirely objective reporter, reporting the
facts, just the facts. Thus, the case of the missing
sonic controls does not appear in a modern mystery
novel, because we all know who did it: we all did
it. When we wanted sonic controls, manufacturers
sold us controls; and when we eagerly sacrificed
sonic controls at the altar of purity, the same
manufacturers stop selling them. In other words,
sonic control was forsaken in the quest for the
“absolutes.”
What are these absolutes? It is as if the
philosophy’s old war between Realism and
Idealism has been fought again between the meter
readers and the golden eared and the war has ended
in a truce that prohibits either side from using sonic
controls. For the scientifically inclined, the absolute
is the electrons themselves. As long as the scope
shows no difference between incoming and
outgoing signals, it does not matter how an
amplifier sounds in your living room with your
loudspeakers. All that matters is the easily specified
voltages and currents created by the electrons.
Engineering has met its conditions of satisfaction,
Imagine if you encountered a telescope
manufacturer, whose product line embodied a
severe minimalism: telescopes built with the fewest
lenses possible, telescopes without eye adjustment
knobs, telescopes without color or polarizing
filters, telescopes without magnification
adjustments, telescopes that were instead built to a
single fixed magnification and fixed position,
telescopes that could reveal only a few celestial
objects in clear focus because of the fanatical
adherence to preserving the all of the purity of the
light entering the telescope; and if you complained
about the blurry image of your favorite star, the
manufacturer would superciliously reply that your
favorite star was not worthy of his telescopes and
that you should be looking at other, better stars —
if you encountered such a strange business, then
you would not see anything that radically different
from what is practiced in high-end audio today.
In high-end audio, it is human beings who were
created for audio equipment and it is they who
must conform to its demands. Thus, balance
controls are rare; tone controls, nonexistent; so too,
stereo/mono switches and, heaven forbid,
equalizers or loudness controls. It is as if the
Puritans’ renunciation of shiny buttons has been
one-upped by the elimination of buttons altogether.
In a high-end salon, played on a $40k system, a
system made up of some of technology’s newest
triumphs, most of your once-favorite albums,
strangely enough, no longer sound good. And
while a few high-quality recordings of mediocre
performances do sound good, they do not
artistically merit a second listening, an amazing
technological feet, considering that your favorite
music was once enjoyed readily when heard
through a car or table radio’s single 5-inch speaker.
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which do not include your enjoyment. Adding a
slight boost at the mid-frequencies would devastate
the amplifier’s 0.0002% distortion rating.
Conversely, for legalistically or religiously
inclined, the absolute is the sound its self. It is the
compression and rarefaction of air at some
unspecified point in some unspecified concert hall
at some unspecified relative humidity, temperature,
and altitude. Although unspecified, this absolute is
known as much as the Earth is known to be only
6000 years old to the fundamentalist (and since he
already know all that is important to know about
the Earth, why bother with geology?). And this
unspecified-but-known absolute is proclaimed by
an exalted few, audio’s new prophets. For these
earnest few, epistemology easily makes the
otherwise-impossible jump into ethics: they
proclaim that any deviation from the known-but-
unspecified absolute is as morally wrong as telling
lies. For these grim few in the know, enjoying the
sound from a table radio is no minor sin.
A lesser sin would be turning up the volume on
the tweeters to compensate for a failing hearing
response at high frequencies. Surely, the nobler
stance would be to leave the high frequencies flat,
as that is what it sounds like in the concert hall, no
matter how unpleasant the music may be at the
concert hall for that reason to the man with failing
hearing. Verily, if a man wishes to partake of a
pure sound, first let him have pure ears. Following
this logic, shouldn’t all eyeglasses have flat, clear
lenses so as not to alter the purity of the light?
What does it matter if the near-blind are unhappy?
Remember H. L. Mencken’s definition of a
Puritan as someone with the haunting fear that
someone, somewhere, may be happy. Happy? Why
would you want to be happy, when you could be
right? But what if happiness was the goal and not
absolutes? Stop and think about the consequences:
if our sonic enjoyment becomes the object of our
efforts in audio design, why then we might just go
on to wanting chairs and sofas to be comfortable,
not just orthopedically correct; office buildings to
be beautiful to behold, not just volumetrically
efficient boxes; and food to be delicious, not just
nutritious.
We would want to abandon singular and
constant absolutes for varied and changing tastes.
Supposedly objective experts would have a hard
time selling absolute audio magazines, as no one
could (at least with a straight face) proclaim the
superiority of his own absolutely correct taste.
Rock ‘n roll, rap, reggae, and modern country
music aficionados could no longer be derided justly
by those who preferred an acoustically pure music
such as jazz and classical. What sonic flavor would
make everyone happy? I do not know; which one
shoe size would make everyone happy? All must
choose their
own
preferences. Without sonic
controls, there can be no choosing.
Admittedly, at least in part, the loss of control
was justified by the elimination of real and
imagined sonic contamination resulting from extra
potentiometers, switches, ICs, transistors, tubes,
and reactive parts in the signal’s path. Certainly, a
poorly designed tangle of wire and parts can harm
the delicate signal. So no argument is being made
for needless and hollow bells and whistles. No,
what is needed is sonic controls that are as lovingly
designed as a Stradivarius was created. So while
part of the loss of sonic can be attributed to poor
design choices in the past, part of the equation was
also the happy renunciation of responsibility.
I remember hearing one famous designer of
men’s clothing answer the question “Why does
designer clothing sell so well?” with the
observation that most consumers had no
confidence in their ability to make valid aesthetic
choices and the designer label freed them from that
responsibility. Think about it: wearing another’s
aesthetic sensibility is as weird as wearing his old
underwear or using his toothbrush. Surely, choices
born of our own private aesthetic sensibility should
be the easiest to make. And if those choices did not
require confidence and did not often result in moral
condemnation from ourselves as much as from
others, they would be easy to make. By choosing
our sonic palette, we must assume the
responsibility of those choices.
Since the heroic is no longer unfashionable (as of
September, that is) let me tell you of one my
heroes.
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Back in the 1980s, a friend and I took a wine
appreciation class. Our class was small and already
well experienced with wine. Our instructor worked
at a winery and he thoroughly knew wine, bringing
excellent examples, taking great care always to
maintain a consistent vocabulary for describing
wine, something woefully missing from audio
practice.
One day the instructor brought in a brown-
bagged bottle of wine and poured us all a glass. We
all sipped at once and we all gasped at once. We
had just tasted Ripple— or Thunderbird? — or
some other wino-favorite given to us as a
reality
test. Some choked and cursed; others immediately
spat the wine out; but one us of us swallowed and
smiled. He eagerly asked the name of the wine and
then said that it was exactly the wine he had
wanted to drink all along, but which he could never
find. He marveled at the money he had wasted on
fifty-dollar bottles of wine. He then stood, collected
his things, and permanently left the class with his
treasure. He knew what he liked and he did not
care what anyone else thought. His heroic act
inspires me even today.
Attribute
Illumination:
Extremes
Dark
Bright
Dynamics:
Compressed
Explosive
Slow
Fast
Rhythm:
Cool
Warm
Temperature:
Width:
Narrow
Wide
Tone:
Thin
Rich
Phase:
Minus
Plus
Left
Right
Balance:
Soft
Hard
Texture:
Recessed
Close
Position:
Depth:
Shallow
Deep
Weight:
Light
Heavy
Height:
Low
High
Wait a minute. Isn’t this more like making a
musical instrument than engineering a strictly
linear electrical circuit? Yes it is, but an analogy
from photography and painting might help ease the
thought of abandoning the objectively linear. Paint
and canvas are not reality, not a woman sitting
peacefully, nor a mountain reflecting a morning
sun. Thus, for the artist to fool us into seeing
reality, he must resort to techniques that overcome
the seeing of just blotches of paint on cloth. When
photography was invented it was assumed that
reality had been perfectly captured. But the
captured reality in photos often looked unreal, so
photographers found that by borrowing some of the
painter’s techniques they could make photos
“appear” closer to real.
Textur
e
Te
mperat
ure
Cool
Warm
Soft
Hard
Dream Line Stage
So if I could have a dream linestage, besides the
usual selector switch and volume control, it would
have at least
twelve
sonic controls. Some of the
controls already exist, such as phase and balance.
But others, such as illumination, dynamics, rhythm,
temperature, width, tone, texture, position, and
depth, weight, do not exist, but should (we have a
lot of work ahead of us). These extra controls
would bring the sound from your speaker under
your control and your entire music library could be
pleasurably played. What then follows is a list of
the controls and their functional extreme settings:
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Besides, there never was a pure, unalloyed,
unbesmirched, virginal audio signal to begin with.
The microphones’ physical construction and
selected position already grossly altered the
sound’s capture. And the cabling and preamps and
mixers that followed further altered the signal.
Then we added the remastering, the processing,
and the conversion to playback media (ADC-to-
DAC or RIAA equalization to playback inverse
equalization) to the signal’s aberrant course. What
signal integrity that might have survived was
finally run through the sound processor known as
your system, playback deck, amplification, cabling,
speakers, and room acoustics included. There
absolutely nothing left of the piano or flute playing
in a hall long ago that is untouched by this long
chain. Still, some argue that we should regard the
record or CD as absolutes in themselves and try to
preserve that arbitrary purity from there on.
But why? All CDs and records come sullied, so
why should we pretend otherwise? Imagine that
you visit a friend’s house and while there you
watch an old Marilyn Monroe movie. You
complain that Marilyn has a decidedly green cast
about her. Your friend assures that the picture is
correct. “How so?” you ask. His reply is that he has
measured the video signal coming out of his cable
feed and the green cast is contained in the color
burst information of the feed. Your friend
adamantly refuses to alter the picture to bring
Marilyn’s skin back to something closer to human,
for to do so would be untrue to the electrons that
trace the cable’s signal.
Should you call the cable company to complain,
they might reply that they have the actual film in
their hands and it has a green cast about it due to
aging, which they do not wish to correct, as they
respect the absolute purity of the film. “Still, a
green Marilyn Monroe?” you think to yourself.
Before you think that I am going start arguing for
an absolute skin tone, imagine that instead you had
found Marilyn’s skin a bit too pink and commented
so. Your friend’s reply is that he purposely adjusted
the color so, as he prefers to see her that way. Is he
wrong? If so, how can someone’s preferences be
wrong?
And if so, is he absolutely wrong or relatively
wrong? And if his preferences are wrong, is he,
indeed, morally wrong for holding them? In fact,
do his preferences even have to be logically
consistent? For example, I once knew a woman
who, when given the choice between cream and
half-and-half for her tea, always choose cream; and
when given a choice between half-and-half and
milk, always choose half-and-half; but when given
a choice between cream and milk, she choose milk.
Was she wrong? If so, how?
So I am saying that we should abandon all
absolutes and logic? No, both absolutes and logic
have place, but that place is not where they have
been misplaced in audio practice. Consider this: is
not the obsession with an imagined absolute sound,
ultimately, at its core, philistine --as philistine as
the meter-reader’s obsession with 0.0003%
distortion. For such an obsession with an absolute
sound exalts sound over music, although the actual
music is not the same as the sound. What? Doesn’t
sound equal music?
When deaf, Beethoven not only created great
music, but he also more profoundly and absolutely
experienced that music than those who could hear
his music only by sound waves. For sound is really
only the usual medium by which the playing of
instruments is brought to our ears, but the essential
aspect of music is experienced in between our ears,
just as poetry is not found in the splattering of ink
on paper or electrons flowing through an amplifier
or even in the flapping of a loudspeaker’s cone.
Thus, a more honest and informed absolute is
found not in the
electrons
and the
sound
, but the
music
itself. Thus we should judge a sound not by
some imaginarily perfect sound, but by how true it
is to the music. Many of the usually disparaging
audio attributes, such as “strident, brittle, and
glaring,” might be perfectly appropriate and
true
to
a certain Shostakovich composition, just as “sweet,
fluid, and warm” would be equally inappropriate
and untrue. In this sense, all un-adjustable stereo
systems are like broken watches: only occasionally
are they accurate. Like the fixed-magnification
telescope of the earlier example, what our systems
need is a means of easy adjustment.
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fed a mono signal, as the image always seems
wider and less spatially specified. Why? Some
of the blame must lie in the disparity between
loudspeakers, differences in frequency response,
mismatching in crossover components, and
different room reflections. And certainly some
of the blame must lie in the disparity between
linestage and power amplifier channels.
Expanding the width requires cross feeding
an inverted phase signal from the opposing
channel (ultimately, this signal should be
frequency selective). A 100% ratio will
completely eliminate the signal common to both
channels, resulting in a extreme separation of
instruments, so extreme that some instruments
will appear far to the outside of the speakers.
A reasonable amount of constriction and
expansion might at the 50% mark for both
adding and subtracting one channel from the
other. How do implement such a control?
Starting with the blending into mono
direction, the plan is simple: place a varying
amount of resistance between the plates of two
grounded-cathode amplifiers. The smaller the
resistance, the greater the blend. Hitting the 50%
mark requires that the bleed resistor equal the rp
in parallel with the plate resistor in a grounded-
cathode amplifier with a bypassed cathode
resistor.
(One great advantage the turntable held over
the CD player was the turntable’s allowing some
sonic adjustment. Increase the VTA and the sound
becomes more aggressive; loosen the cabling and
the sound becomes defuse. The problem here is
that the adjustment is not easy.)
Let’s be honest: much of the stereo gear and
accessories made are no more than un-adjustable
tone controls. We choose a certain patch cord that
lessens the sizzle from the tweeters. We buy oil-
coupling capacitors to undo the harsh artifacts of
modern recordings. And there is nothing wrong
with these practices other than they are not very
flexible, as different songs on the same album often
require different sonic antidotes. Changing
coupling capacitors per song is too much to ask.
Even changing a knob’s setting per song is asking
too much. (Once a twelve-knob linestage is
created, the best addition would be a
microprocessor that would keep track of each track
and automatically apply the last used settings for
that track.)
Making the Sonic Controls Work
Each sonic control requires making some
change to the circuit. It might be as little as
increasing or decreasing the idle
current. Or it might be as complex as switching
types of tubes or even circuit topologies.
Switching between different coupling capacitors
and plate resistors might be needed. Varying the
amount of feedback while co-varying the input
signal might also be useful in certain sonic
controls. The hard part is correlating the desired
sonic signature with some aspect of the circuit
that can be switched in and out of the circuit.
Only a few of the controls can be presently
implemented, as our ignorance of the
psychoacoustics behind the perceived sonics and
electronic circuits is depressingly vast.
Ra
Ra
mono stereo
left
right
Rk
Rk
Width Control: Narrow and Wide
Combing the left and the right audio signals
into one narrows the sonic stage width by
creating a mono signal. Interestingly, the result
seldom sounds like a single loudspeaker being
But the cathode resistor should be left
unbypassed, as an unconstrained cathode will be
needed to implement the broadening of the
signal. With the unbypassed cathode resistor, the
resistor value for 50% must equal:
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