Es gab 1961/62 bereits einige Transistor-Verstärker - aber keinen auf dem qualitativen Niveau eines CITATION A

In Zeitzeugengesprächen mit den alten Haudegen der 1970er Hifi-Jahre fällt öfter der Name "Stewart Hegeman". Er hatte für die damalige Zeit zukunftsweisende visionäre Ideen und bei Harman Kardon konnte er die verwirklichen. Doch das alleine reichte nicht, denn es gab bereits eine handvoll kleiner oder kleinster sogenannter "Startups", wie es heute in 2019 heißt.

HK mußte mehr anbieten als nur Transistoren. Diese Germanium Typen hatten einige Macken und darüber stolperten "die anderen" und verschwanden wieder vom Markt. Die Werbung mußte die Vorteile der neuen Technik eindrucksvoll herausstellen und in den großen USA mußte es bereits eine aktive Händler-Dichte geben, damit Interessenten das auch mal in Natura hören konnten.

Bei HK gab es gute Voraussetzungen für neue Produkte

Mit den bisherigen HK Hifi-Produkten - alle auf Röhrenbasis und teilweise noch in Mono - hatte sich HK in der Branche und bei den Händlern bereits einen guten Ruf erarbeitet und so viel es nicht ganz so schwer, diesen neuen Citation A zu bewerben.
Wir haben da eine erste Anzeige aus der US-AUDIO vom October 1962 virtuell ausgeschnitten, in der die Eigenschaften publikumswirksam aufgelistet waren.

Die Presse-Info in der US AUDIO im October 1962 :
THE CITATION A

+0 -1/4db from 1 to 1,000,000 cps.That's the bandwidth of the new Harman-Kardon Citation A - the world's first professional Solid State (transistorized) Stereo Control Center. It is totally new in concept, design and performance. When you hear it, you will share the experience of its creators - the experience of genuine breakthrough and discovery; the experience of hearing music as you've never heard it before. Citation A represents a towering achievement for Stewart Hegeman and the Citation Engineering Group. It will change all of your ideas about the reproduction of sound. Visit your Citation dealer now for an exciting premiere demonstration.

For more complete technical Information on Citation A write to the Citation Division, Dept. R-10, Harman-Kardon, inc., Plainview, N.Y.

AUDIO OCTOBER 1962 - Page 37

In späteren Ausgaben gab es Beihefter-Einlagen

Das sind ein- oder zweiseitige Prospekte auf deutlich festerem teils 120 Gramm Papier gedruckt und mitten im Heft eingearbeitet oder geklebt. Und dort stand natürlich wesentlich mehr drinnen samt Bildern oder es gab sogar Fotos.

1962 - THE CITATION A

+0 -1/4db FROM 1 TO 1,000,000 CPS WITH NO MEASURABLE DISTORTION

Chapter I

Citation represented a major breakthrough in high fidelity design when it was introduced three years ago.

Anmerkung : Der Transistor wurde zwar bereits 1947 entdeckt und entwickelt, aber es dauerte schon noch etwas, bis er in die Audio Entwicklung einfloß. Erst der Übergang von Germanium auf Silizium beseitigte die gröbsten Macken dieser neuen Technik, die Temperaturabhängigkeit.

The "Citation Sound" became the industry standard and audio authorities agreed that Citation was unsurpassed for professional or home use.

An important new design philosophy was involved in the development of Citation. H-K engineers found that performance in the non-audible frequencies strongly influences performance in the audible range. This was confirmed by critical listening tests with the program material carefully controlled.

Every Citation instrument reflects this basic design philosophy. Each reproduces frequencies two octaves above and below the normal range of hearing. Each provides unsurpassed performance: tight, clearly defined bass and clear, transparent highs.

The state of the art at the time Citation appeared did not permit the design of finer high fidelity equipment.

During the past two years a new technology has emerged: transistors. They offer significant benefits including lower heat, lower noise and longer life.

But most important, the transistor removes the limitation on frequency response (bandwidth) imposed by the vacuum tube. For the first time, audio engineers can design high fidelity instruments capable of reproducing frequencies in the megacycle range.

It was now possible for Stewart Hegeman and the Citation Engineering Group to once again advance the art of high fidelity design. The Citation A - the world's first professional Solid State (transistorized) Stereo Control Center is a brilliant expression of this advanced technology.

It is totally new in concept, design and performance. When you hear it you will share the experience of its creators - the experience of genuine breakthrough and discovery; the experience of hearing music as you've never heard it before.

Citation A is truly a towering achievement. It offers features and performance never before attainable in audio design: virtually unlimited frequency response (+0 -1/4db 1 to 1,000,000 cps), unmeasurable distortion and perfect phase linearity.

Chapter II

There was a parallel development at Harman-Kardon that made a major contribution to the final design of Citation A. The company's Data Systems Division was perfecting advanced construction techniques for the use of micromodules in missiles and computers. The essential requirements of that complex technology are absolute reliability and consistency in meeting the most exacting specifications. These very same techniques were applied to the design of Citation A.

Anmerkung : Also auch Harman Kardon entwickelte fürs US-Militär, ähnlich wie BOSE und viele andere US-Firmen. Auch das war damals so üblich, wurde aber seltenst an die große Glocke gehängt.

For example, each of the seven stages of gain is mounted on a separate glass epoxy module. A new (pat. pending) temperature sensing system surrounds each stage. Each individual circuit is automatically stabilized against the most extreme temperature variations. The result: unmeasurable distortion - less than .05% from 40° to 140° Fahrenheit.

The use of glass epoxy boards assures uniformity and strength. Each stage of gain receives thorough in-plant testing for noise, gain, distortion and square wave response. (The most accurate measure of the tone quality of an amplifier is the purity of the square wave. Citation A has a perfect square wave response with a rise time of less than one microsecond.)

Each module is slotted into a computer rack panel. Each provides 33db of gain with 34db of overall feedback. This unusually high degree of feedback results in lower distortion, improved tone quality and elimination of listening fatigue.

To maintain the stability of a preamplifier with a low frequency cut-off of one cycle, the power supply must meet very rigid requirements. The Citation A power supply incorporates four Zener diodes and two transistors in a special new design which insures perfect regulation. No variation in line voltage can affect its stability or performance.

A hermetically sealed reed relay designed for high speed computer operation keeps the preamplifier turned off until the power supply has reached full regulation.

There are two separate on/off switches which act independently of each other. One turns the entire system on and off, the other turns only the power amplifier off when listening with headphones. (On the following page you will find a complete listing of Citation features and specifications.)

The Citation A is strikingly handsome and remarkably simple to operate. It will measurably improve the performance of any stereo high fidelity system.

The Citation A, Kit....................$250.00
Factory Wired ..........................$350.00
WCA, Walnut Enclosure............$ 20.00

The First of a Series of Definitive Instruments for High Fidelity:

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The New Citation A by Harman-Kardon - The World's First Professional Solid State Stereo Control Center
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THE CITATION A
Professional Solid State Stereo Control Center

• Separate bass and treble step-type tone controls for each channel. Controls electrically out of the circuit when in the flat position to eliminate phase shift and transient distortion.
• Convenient front panel stereo headphone receptacle.
• Special broadcast-type scratch filter incorporated into treble cut positions for sharp roll-off without ringing.
• Separate turnover and roll-off equalization switches to compensate for all records and tapes.
• Solid-state fully regulated power supply employing transistors and Zener diodes assure extended low frequency and excellent transient response.
• Individual amplifier and system on/off switches allow listener to turn off power amplifier when using headphones.
• Separate front panel tape head adjust controls permit accurate equalization calibration for tape head wear.
• Low impedance emitter follower output permits the use of long connecting leads without affecting frequency response.
• Glass epoxy modules mounted in computer-type rack panel for rigidity, professional appearance and easy accessibility.
• Four ganged, close tracking gain control assures low noise and perfect control of volume.
• Heavy duty potted power transformer.
• Center channel output with separate gain control.
• Push button switches for Stereo Reverse, Contour, Tape Monitor and Low Cut filter.

SPECIFICATIONS

Frequency Response: From one to one million cycles per second, +0 -1/4db.
Square Wave Response: Better than 1 microsecond in all function positions. (Tone controls flat.) Less than 5% tilt at 5 cycles per second.
Harmonic Distortion: Unmeasurable at 2 volts output from 20-20,000 cycles per second.
Intermodulation Distortion: Less than 0.05% from 40°to 140° fahrenheit at 2 volts.
Noise: Low level phono: 70db below rated output at 5 mv. input reference. - High level: 85db below rated output.
Sensitivity: High level input: 0.25 volts. Low level input: 1.5 millivolts.
Rated Output: Two volts. Six volts maximum.
A.C. Convenience Outlets: One individually switched for basic amplifier only. - Three switched with preamplifier.
On/Off Switches: Two individual power switches. One controls the power for the basic amplifier only; the other, the power for the preamplifier and associated equipment.
Function Selection: Six positions: Auxiliary. Tape Amp., Tuner, Phono 1, Phono 2, Tape Head.
Mode Selector: Five positions: Stereo, Blend, A + B, Mon A, Mon B.
Blend Control: Introduces variable amount of crossfeed between channel A and B. Rear section of control acts as center channel gain control.
Equalization Control: Separate Turnover and Roll-off to set individually, the equalization of the low and high frequencies. Turnover: Tape Adjust, NARTB, 800/RCA, RIAA, LP., AES, 78. Roll-off: 0/78, 4/FFRR, 10.5/ OLD LON, 12/AES, 14/RIAA, 16/LP.
Anmerkung : Es gab also Schalter für die noch immer sehr gängigen firmenspezifischen Entzerrungskurven der Plattenhersteller.
Tone Controls: Professional step-type controls for each channel. Electrically out of the circuit in the flat position.
Balance Control: Zero to infinity type; frequency insensitive.
Contour Switch: Compensates for Fletcher-Munson effect at low listening levels.
Channel Reverse Switch: Interchanges Channel A and B for proper listening orientation.
Low Cut Filter: Two position: Flat, 75 cycle cut.
High Frequency Filter: Five positions incorporated into treble tone controls. Special non-ringing circuit.
Tape Monitor Switch: Permits monitoring of tape while recording.
Output Receptacles: Four main preamplifier outputs. One center channel output. Two tape outputs for recording.
Total Number Of Transistors: 33.
Special Features: Push-button selector switch, stereo headphone receptacle, special front panel tape head controls to trim equalization for any tape head. Cabinet installation from front with escutcheon remaining fastened
to preamplifier. Simple attachment to mounting board.
Dimensions: 14%" wide x 5%" high x 7" deep.

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For complete information on all Citation instruments, write to Harman-Kardon, Inc., Dept. A-ll, Plainview, New York. (Export office: E.M.E.C, Plainview, New York. Canada: Chas. W. Pointon Ltd.)
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