Archeons, the human to light speed interface.

Ancient Mystical Knowledge and its Light Speed Audio Analog.

Many folks don't need a lot of knowledge of amplification to obtain a 'hi fidelity' sounding sonic field.
People do need to know a lot about sound to be sure the amplifier and preamplifiers provide quality sound.
An Amplfier that uses a preamplifier is called an archeon. The Name originates from what Hollywood movies
like to call 'ancient greek literature', but what is actually egyptian crypt texts about the tens years after
the reserection of Jesus of Nazareth and the knowledge given during that time to his disciples. It also fits
the ergonomic idea that humans interface to high speed signals most often by using this part of the audio,
sometimes in the form of mixers which acts as a preamplifier. Lastly, the name is associated with some abstract
kind of 'bad boy' in the greco-roman-egyptian gnostic literature and all the divisions of spheres of powers.
Hollywood avoids any reference to real Egyptian classics like the 3rd and 4th century gnostic scrolls found
in Egypt, perhaps because movies like Star Wars would appear as obvious re-writes as would many characters
found in western Christian style religious mythologies and litergical traditions. Princess Leia, for instance,
is a little bit like a stunt double for the character of Pistis Sophia in the gnostic (knowledge) texts.

The experience with preamplifiers is often a little mysterious, even for professionals. To begin with,
there are newer standards for interfaces as every generation of technology makes its own revolution.
Right now, a transition to +20dBu output (in Europe +18dBu) is gaining acceptance. As you might expect if you
have experience, this will pretty much burn up any sensitive power amplifier designed for plus +4dBu and burn
the right channel of the prolific minus 10dBV consumer grade power amplifiers, stereo surround sound or auto amplifiers.

The semi-pro -10dBV amplification runs out of headroom and sounds strained. The only solution is to go digital.
If you have a lot of CD's recorded at older peak standards, you need digital conversion with sensitivity control.
Just to begin with, the CD's signal for -10dBV is only 1/4th that of +4dBu, or about 0.447 peak volts.
These new standards were intended to allow digital equipment to match the extra loundness for peak signal
called headroom that is available in analog standard recordings, such as CD-R or vinyl. The result has beeen
unexpectedly bad. The difference between live sound requirements and post-production was not anticipated.
What is required is switchable gain structures or adjustable sensitivities, and there are no sound cards
at all that have such features. These are only found on expensive studio digital mixers or KennedyAudio.com
amplifiers and pre-amplifiers, or at least their analog counterparts are found there.

Standards for interfaces changed away from the telephone standard of 'equalized' (early term for balanced)
sound at 1 volt and 600 ohms (DC resistance of isolation primary coil later revised to 1000 for -10dBv
to best match transistorized frequency equalization profiles and stereo systems) in the 1960's. Since then,
audiophiles have been chasing the rare input impedance matching transformers at great expense and effort.
Here we go again.

The weakness in the right channel has to do with the balancing of circuits, even though a power amplifier in
solid state is rarely spoken about in terms of its balanced versus unbalanced design. The reason is that with
a power amplifier that does not use an internal or an external preamp, sound is not changed so much just because
of the way that the circuit works. But it needs to be changed. The typical source is unbalanced and a good
example of Garbage In - Garbage Out. Think of a speaker as a motor. It can be driven forward or reverse.
The source will give you only forward drive and complete the cycle on one wire, the other is neutral or ground.
One way a preamplifier works is to convert the 1.4 volt unbalanced single line signal into balanced 2 lines.
This restores the ability to provide more current for the power amplifier, which would lack bass tone otherwise.
Often the preamplifier does more than just that. For instance the power supply it uses effects the sound quality.
Tube preamplifiers have been popular where low sensitivity power amplification is used. They are tolerant to
overdrive voltage distortion and can also provide underpowering distortion if wanted, but they make more noise.
Still, if the signal coming in is intended to sound square wave, metalic and distorted or noise like, this is OK.
With consumer grade unbalanced power amplifiers, the mismatch between 4 ohm speakers when 8 ohm is the design
target is much less of a mismatch than if the power amplifier were a full bridged design. More possible
variations on a basic design type of power amplifier are possible while holding constant the output matching
to speaker impedances. Therefore the muliple taps for 8 ohm and 16 ohm speakers became obsolete long ago.
There are so many factors related to saving either the speakers from overload or the power amplifier that
the mystique of otherwise well understood solid state amplifier technology is safe for a long time to come.

In almost any case - the character of sound is added into and enhanced or 'colored' or contoured
into the signal by pre-amplification of some kind. That can be a small 1 volt internal preamplifier which makes
the power amplifier into what is called an integrated amp. It can be a maxmimizer used by many DJ's to drive
a Crown amp into JBL speakers, the a common match right now. It can be a mixer or digital signal
processing unit (DSP) in either hardware or software inside a computer or sound card. Signals can be
changed to sound like a musical instrument of any kind by virtual signal transforms (VST) or into any
amplification system from mechanical pipe organ all the way through classic guitar amps with tubes or transistors
to Moog synthesizers oscillators and filter waveshapers and effects. A complany called Line 6 offers a wide line
to make a guitar into anything from the Mesa Boogie used in Smoke On The Water by Deep Purple to the sound of
the London Symphony Orchestra's Steinway piano. All this is done with as little as a single 'LINE INPUT'.

With the exception of tubes (versus solid state discreet transistors and transistor arrays; op-amps)
all this sound change comes from the preamplification stage, which spans from about 1/2 volt to 1.4 volts
for amplifiers under 25 watts to about 10 volts for higher power applications. Another exception is the
general rule that without any preamplifier, you will get a kind of sound that ignores entirely any sub-sonic
input and responds at nearly inaudible levels to any input signal below 40 hertz. But that exception applies
only to solid state devices. This fact has to do with the physics of a semiconductor, which is what a solid
state transistors is. It is a barrier to the passing of high power through it. The signal changes the state
of the device so that power can pass through it. Amplification is achieved by allowing power to flow.

A tube amplifier uses a heated wire between two plates or grids. The wire is giving off electrons as it glows
and the signal is made to pass through it by the differences in the positive draw and excessive electon count
push on the plates. Amplificaion is achieved more like a pump. The term valve was used for tubes so long ago
that the name stuck, when really a semiconductor acts like a valve in liquid and hydraulic power transfer.

We just covered a lot of technology, but what we said was that higher frequency sounds and mid-band music
pass easily through any amplification system. You can plug a CD player directly into a power amplifier of
any kind and its 1 volt output at a few thousandths of a ampere of power will be enough to enjoy the music's
so called hi-fidelity content. All that you will miss is the bass and mid-bass (preamp prunella) and of course,
the music will sound much less enjoyable than IF you had a pre-amplifier. Does it always sound better
with any pre-amplifier? The short answer - yes. The long answer involves the unavoidable complication -
that what sounds good may not actually be good. It's just like high calorie foods that taste good but are
really bad or smoking a cigarette that feels good but may not be, or even like hitting your thumb with a hammer
to drive a nail when it gets the job done but does more damage than the job is worth sacrificing. Signal sounds
cold without some form of enhancement. It sounds even more cold in solid state than in tube ampifiers, but it
also sounds chilled in tube amplifier that do not use a seperate tube pre-amplifier stage before the driver tube(s).
The amount of stereo image - that aspect that makes it sound spread out in space with different point sources -
can not be achieved without both sensitive speakers as well as a 'fast' or high 'slew rate' amplification system.
The rise time of higher speed signals often exceeds the ability of tube amplifiers to respond, as is the case
if they are fed a triangle wave from an audio oscillator. But because this kind of distortion is one example
of a distorted signal that sounds better than its original analog it can be used to add a seperate track or to
mix with an existing signal or even to limit the rise time requirements for accurate playback on any given mixdown.
Many sound enthusiasts don't care much about slew rate because they know this specification only has an impact
on higher frequency sound reproduction, and their focus is mostly on bass. Dance floors just do not use much
midrange and tweeter or horn drivers. They buy amplifiers with easy EQ interfaces built in for computer control
and special presets for JBL speakers, which Crown has provided for a very long time for bar and DJ rig owners.
The ability to be stable down to 2 ohms may not be popular either as a portable big gig rig should probably
use the high power bass driver amplifiers in bridged mode rather than in stereo mode, to be fully balanced.
This is why we sell the Kennedy 500 as a bass guitar instrument amplifier, in single channel, even though
if some wanted to use it in DJ rigs, a second channel could be added for another $500. This covers the cost
of hand selecting and matching the extra 6 bipolar transistors, a second fan and its layout heatsink and assembly.
One advantage of doing that would be to use crossovers at the speakers, which we do not usually recommend.
Recently we compared out 2228h with a Fane, crossed over to 2 mids/tweets and driven in parallel with the JBL.
The result was very favorable. Even though we sell crossover units for the preamplifier line level, there is
an old school of thinking that likes the extra protection and access to crossover capacitors for reliability.

The majority of pre-amps are made just because they add lots of distortion, carefully chosen to give a character
to hardware devices. This means that a good signal going in can be changed into a 'better' one and a garbage signal
in can be an acceptable signal coming out. That is the advantage of signal distorting highend pre-amplifiers.
It is also the reason why it is so hard, actually impossible, to find a slew rate of a power amplifier that has
a voltage slew rate matched to its own wattage output and to its target preamplifier. Only KennedyAudio.com does
that. Of course digital signal processing lets users select the type of distortion added and compression in many
cases, but whenever they do not, the listener is not informed that the signal coming in has been altered or in what way.

It's just that tubes often do not get scrutinized because the pre-amplifier is almost always integreated into the
same houseing or box as the power amplifier. The signal needs to be expanded and routed to different transducers.
A DJ will always want to expand the bass into a gutt punching shock wave in addition to getting the bass section to
sound louder than the midranges. Then again, a disco DJ just might not want so much emphasis on the bass or the
punch, but want to allow midrange as long as it doesn't make everyone on the floor go home with a headache and
bleeding ears. But some people get headaces from too much bass and don't have a problem with midrange and highs.
This is the equalization and crossover network. Some form of it is almost always found in preamplification.
And in addition, many vintage stereos used crossovers after the power amplifier as well. This helped in name
branding and recognition. It helps give users the size of speaker boxes they want with the power they want to pay
for and the speaker sensitivity that they prefer.

They often prefered lower sensitivity speakers, so crossovers and dividers were common at the transducer stage.
Capacitive filters are still used and always will be at the speaker stages because they defeat the bass signal
and pass the upper range high power signal and thus enhance and protect valuable speakers. They appear on the
treble transducers where the cost of the capacitor is lowered because the voltage going to the speaker,
and certainly the wattage, may already be buffered by a midrange speaker that is in parallel with it,
making the pair of mid/treble tweeter and bass driver a simple 2 way system, by subdivision into another sphere
of power or into a four way matching response system. Only by doing that the Treasury of Light that is
hidden inside the signal can be revealed in its full beauty and impressive potential.

Decisions and Choices. The more modern and the
Vintage Name Branded Options.

It starts to become a little unwieldy when decisions must be made about preamplifiers. There are many factors
to consider. For one concern, the power amplifier spans a wide sensitivity range just like speakers do, and that
number can make a difference between sound that the ear can barely hear to having the windows of a house explode
outward from the pressures. Some amplifiers respond down to one millivolt. These are the best and most versatile
to match to any speaker, but they also pick up any noise on the incoming signal. So, it may be not be possible
to use amplifiers with something like a very compact and high gain to watt ratio voltage controlled amplifier VCA
unless the signal is made to pass through a noise filter. Most informed decision makes would opt not to use a
noise filter but to change the pre-amp to better match the more expensive and hard to find power amplifier.
This choice is especially true because, by the time one gets up the price scale to high sensitivity amplification,
there have been many other possible choices, one of which is to change out all capacitors on a vintage amplifier.

Potted VCA's where the circuit is not accessable will not allow noise filters to be added to the input section.
All this so far, we have said because it applies to the kind of power amplifers that Kennedy Audio designs.
We feel that we like to tell our fans and customers what they need to know rather than what they want to hear,
but even if we were not so concerned about them, we would need to give them some guidance anyway, just because
we do not expect them to buy every component that comes between their sound source player and their ears from
us, using online buying and search engine based advertising and web tool based marketing. We think that in time,
many DJ's who haul around heavy amplifiers and speakers will realize that our units provide efficiency of choices.
Our units weight is comparable and so is our speakers weight, but you don't need another unit for the horn set.
Also, given a choice between buying and carrying 2 JBL horns or two seperate treble amps/preamps, choose horns.

There are different classes of amplifiers. Are there classes of preamplifiers? No. Why not? Well its complicated
and envolved. How many famous guitar players use solid state amplifiers? Can any of your friends name one? No.
Why not? Well, it is complicated and envolved. There are almost no solid state pre-amplifiers that a guitar player
can try. A few do come to mind; Marshall, Peavey, Digitech, the HH 'MA80', Traynor '/Group One'.
These last two that I happen to own, but I think it unlikely that any reader of this article owns one or ever even
heard of them. The most obvious reason is that to get sales and accelerate sales growth, it pays the builders of
amplifiers to put a pre-amplifier into their power guitar amplifiers and just sell it as either a branded kind of
sound or else some boutique model of special interest. Most are tubes or digital. When solid state, they are pedals.
But solid state's compactness allows us to build a great full cabinet H-bridged 75 volt/microsecond slew preamplifier.
The preamplifier is tested with Kennedy amplifiers and signal frequency splitters and works for everything, not just guitars.

Pre-amplifier classes would likely be split into op-amps and discreet transistor classes, the second of which could
be very small and fit on the head of a pin, or the tip of the pin of you don't need much wattage. You could make a
quick third class with tubes. If you get creative you could say that voltage controlled amplifiers are a class because
they offer a new way to interface and control the signal, but then you are really not talking about HOW they amplify
but how you as a person act. And that makes the discussion turn into one about Archeon classes.

It is easier and less unwieldy to use the idea of Archeon classes instead of power amplifier's class. Just to begin
a discussion of why this is better, I could ask the reader what class that they would guess that a MOSFET power
amplifier would most often be? Would you guess class-A? Perhaps one that could switch at about 680 milliampes or
say 60 watts from pure class-A into class B mode where it can supply more power - just like the Kennedy Audio 500
used to be built?

What is class A/B? Hint - the Kennedy 500 was not MOSFET but bipolar transistor based. You already know
it was at that time a class A/B, but now stays in A-class with better control of the offset bias. So are there any
class-A MOSFET amps? The MOSFET is the lowest distortion transistor type and very powerful. Another hint- they
have a tendency to get very hot. So are they usually not class-D which most car amplifiers are. Who wants a hot
amplifier in their trunk. Ok, then consider that they have a tendency to actually blow up in a little explosion
of sorts. You are right, they are never used as class-D. Stereo enthusiasts love them and use them a lot.
Sterophiles almost always end up buying class A. You are right, again, MOSFETs are NOT class-A. The industry gives
them a number of other classes : F, H, or often they avoid the term class and just say it is 'good'; a 'workhorse'.

They take the power that the transistors are capable of switching and say that this is how may watts of power the
amplifier has, and, what can match that in your 'class' kinds of amplifiers? If we did that, Kennedy audio's 500
watt amplifier in bi-polars would them become an instant 1600 watt and we would not have to change anything but to
add 1600 watts to a decal sticker or front bezel or foil hotstamp. This is why efforts by the Federal Trade Commission
and to get amplifier manufacturers to rate their wattages in some intelligent and consistent way have all failed.
Auto amplifiers that do not use the transistor power often rate their amplifiers at 0.5 percent distortion.
The Kennedy amplifier is rated at 500 watts which is essentially its distortionless output or at about .05 percent.
Of course, to be fair, any amplifier used in a noisy enviroment like an auto interior does not need to be rated
at its clipping onset, but that depends on how it sounds when clipped. Some clipping is good to listen to for a while,
but long term exposure can be a bad idea. So, an amplifier used in a Mac truck rated this way may be OK while the
same amplifier installed in a Kenworth Texas large car cruiser would be a very poor choice of applications.

It depends too much on the characteristics of the power amplifier that you make and sell the most of, and to whom.
If that happens to be MOSFET, it would be a very bad idea to go along with the crowd and use the terminology of amp
class rather than wattages because that would favor the competition. If purely signal PRE-amplifiers, which we
have just explained, are the important factor concerning tayloring sound character to what you need or would
like to even explore, then how bad is it going to get when we start talking the talk and walking the walk of the
general amplifier classes? What we need to understand is the entire Archeon spheres of power contouring, their
interface standards and versatility. We need a way of speaking about them in generalizations, not power alone or
their circuitry's quadrature controls.

We could classify archeons as microphone pre-amps and guitar pre-amps or music and movie playback pre-amps.
All three of these have a wide enough range of prices, types, styles, output volts and milliamps.
The sound of a microphone is said to be highly corelated to the speaker or singer's voice, making it
a very personal preference to many professionals. That would leave out the automotive crowd, which may not
be such a bad thing, unless we started with the typical speaker sensitivity, which in automotive would be
the very lowest sensitivity. Why don't we try that. We can keep class D for them, make class miCrophones
and class B archeons for Bass and other guitars. Class A, which is obsolete in this digital age could then be
reserved for the mostly digital and DSP intensive pre-processed and compressed sphere of power which
is the movie, 2 inch standard tape mastered sound. A reel to reel tape has on it at least 10 times more
information that is captured by 24 bit sound samples taken at a rate of 96 kilohertz per second.
This is why any recording studio from Nashville to Hollywood is making their first recording of any artist
group using the good old reel to reel magnet tape.

Of course the method of capturing, whether magnetic or digital, has nothing directly to do with what output
impendance or input resistances are used on the inputs of any device. A tube will use resistances on the
inputs of 240 KilaOhms to match it with what signal is coming in, and requires an output transformer to go
out in almost all cases with some special long cable exceptions, but they use a transformer at the input end
of the receiving device anyway. The tube power amplifier doesn't know if the input will be balanced or unbalanced.
It can provide for both in a simple way, or by adding a center tap transformer, for which Jensens are well known,
to make an ideal match for either type of input. The same holds true as we go down the line from high impendance
tubes to the highly eclectic +20dB equipment with lower input matching to plus 4 so called Pro audio to the
consumer grade minus 10dBV.


The more modern Archeon Amplifier Classes terms.

It will become aparent that efforts to link archeon to classes results in what is really a span of classes that
any given archeon would work well for. A microphone pre-amp (class C) could be used as a guitar pre-amplifier,
which would be a class B. Likewise a class-A pre-amplifier is often so close to a bass guitar amplifier, that
it becomes a sticky wicket to differentiate a class A archeon from class B archeon.

The best solution if we stick with common sense and commonly used terms of a more modern age of here and now
is to discuss interfaces that change sound as class A/B and class C/D and then class E/D, the E for
and others that are too compact, weak, noisy or insensitive to be used class A power/preamped system amplifier,
or if the would unlikely be biamped into a splitter circuit application. We want to use the term Class-A to relate to accessability of the inputs to the
preamplifier section, both to assure the ability to interface a wider range of devices and to eliminate noise.
A classic example is a guitar foot pedal, which acts as a pre-amplifier but is usually easy to bypass.
Then, if we would wish to talk only about power amplifiers, a Pure Class-A means one with a slew rate that
is high enough for the .05 percent distortion output sine wave supplied either integrated or seperately
with a matching slew rate preamplifier, both having more than one possible input impedance or balancing.
Class B would be NOT Bridgable, but otherwise highly sensitive amplification and high wattage hi-S Speakers.
The wattage requirement should depend on slew rate, but there is no good standard for amplifier wattages.
Because transistors are widely available at 50 Million Volts/Second this should be used as A-1 typical.
Keeping the quality control meaning of the word typical, it means everywhere, then both amp and preamp
are A1 and if not it is Archeon A-2. Again, A for access, number following for higher slew, broad band.

The D would indicate an amplifier built to digital circuit standards. These are not repairable at the
component level. Even a small spot of solder would add too much capacitance to the delicate connection
for the signal to remain acceptable. Auto already uses class-D so this is not confusing. Class A/B would
now be used wherever high sensitivity speakers AND high sensitivity amplifiers are used, but only along
with an open, transparent 'above board' preamplifier. Thus the preamplifier, if built in, should have some kind
of controls beyond just bass boost, which is normally added by preamplification or even a 1 to 1 buffer stage
with no amplification at all.

Class B/C would be less sensitive, for more line noise, poorer shielding or tubes, but still capable of capturing
tiny currents. Guitar output and microphone output, phonograph preamplifiers and amplifiers would fit there. This catagorie rarely uses such ear output combined sensitivity levels like 116dB JBL 2 inch horns or the 103dB Kennedy
reproduction of the JBL 2228 wide range transducer, they do not fit into class A/B. They may fit into class B or C
if such an equipment upgrade was being considered. Theaters and arenas with loud sound could easily fit into
class B such as a public address systems that rarely need digital processing but nevertheless need noise guarding
and feedback controls that restricts it from a class-A rated system. A good guitar rig could become class-A if
it were open to either multiple signal level input or modification of existing jacks and impedance matchings.

We admit, this is all pretty simple and basic. If you want to talk to a sales person intelligently about buying
a McIntosh higher end 6550 tube amplifier and you know you want a silky sounding midrange and sweeter sounding
square waves with lots of compression, a very flat and accurate profile to reproduce the original, even to the point
of monitoring the signal for a decision on which your reputation as an agent of the final approval of a mixdown rests,
this information will leave you a little short of the required pre-requisite course in H-bridged power output with
and without the intents of the designer to allow a stereo two channel amp to be bridged into one channel, and the
speed or slew rates of the preamplifier to power amplifier ratio, the signal to noise and minimal required filtering
for the full balanced Jensen +4dBu input section with humbucker lifting of the center tap as an option and DC offset
digital readout and fine adjust with negative fee-dB-ack phase control both front panel mounted for quick adjust and
maybe a few other goodies you will need to survive in your job as an artist's audio approval quality consultant.

So, you may ask, how could your reputation ever be at stake if you have good ears, listen a lot and test for noise?
Well for one thing, the idea of a 'flat' sound profile is not the same thing as the idea of an equally damped flat profile.
That is to say, just a scan of frequencys showing equal input is resulting in equal sound output does not tell you IF
and this is a BIG if, the same equality holds when the input is only loud treble versus the level of loudness when
for purposes of explanation, the input is only soft low sound pressure bass notes. Digital has a problem with that ratio
due to what has now, in the digital age, become known as 'headroom'. In the old school days, headroom meant that, if a
boosting circuit or a specialized note of music needed to include extra harmonics beyond the usually highest 3rd or 4th,
up to say the 7th or 9th harmonic of an instument like a tuba, the system would not attenuate it, which is why vinyl records
with high impedance highly sensitive needles was considered to be the finest source available for recorded music playback.
For tape media, headroom simply meant the highest frequency that tape, and later metalized tape, could retain magnetically.

But at least now you know enough to understand why so much jargon gets tossed around so fast, and why we decided
to build a pre-amplifier as a seperate unit to match as best as possible the timeless Kennedy 500 single channel
voltage and current drive power amplifier; and, of course, why we built the preamplifier in stereo.

For reference,
here is an article on power amplifiers we have been using for 5 years now
and plan to phase out as we add more information about the Kennedy Audio Dark Arts / Quintessence pre-amplifier itself
and as an Archeon for other forms of audio control.


article by KA webmaster : John R. Holsen
From the Audio Tech Stuff page...

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