Harman Kardon Citation II (1958, produced 1959–1960)
At 66 pounds and 60 watts per channel, it was the heaviest statement American audio made in the late 1950s.
Overview
The Harman Kardon Citation II is one of the most famous vacuum tube power amplifiers of all time. It earned that reputation by being better than what came before it. Introduced in 1958 and designed by Stewart Hegeman, it was the power amplifier of the Citation series, a coordinated lineup that also included the Citation I preamp and Citation III tuner. It was Harman Kardon's flagship in the late 1950s and early 1960s, built with one directive: be the best amplifier that money could buy.
At 60 watts per channel, the Citation II was the most powerful amplifier of its era. That alone would have turned heads in 1958. Hegeman got there with a fully regulated power supply, a dual-mono design, and no negative feedback at all. Frequency response was rated at ±1 dB from 20Hz to 20kHz, and total harmonic distortion was rated at no more than 0.1% at rated output. The signal-to-noise ratio of 90 dB meant the amplifier was essentially silent until the music started.
The Citation II was also the first amplifier to use the KT88 output tube, a valve that would go on to define high-power push-pull amplification for decades. Four KT88s per chassis, driven by a 12AU7, a 12AX7, and two 6CG7 driver tubes, delivered the 60 watts with an ease that smaller amplifiers couldn't approach. Input sensitivity was 1.2V for rated output, so it paired cleanly with the Citation I preamp and virtually any other quality source of the period.
Key Features
Zero Negative Feedback Design
Running the Citation II with no negative feedback was radical for its time. Most amplifiers of the era leaned on feedback to flatten response and lower distortion. Hegeman believed it robbed music of its life. Audio (February 1961, p.45) described the amplifier in its advertising as bearing "eloquent witness to the one vital aspect of audio" - a listening experience where "shading stood out clearly and distinctly for the first time." The trade-off was a design that demanded exceptional quality from every other component, particularly the output transformers.
Massive Output Transformers
The output transformers on the Citation II are the largest of any amplifier of its era. That wasn't vanity. With no negative feedback to correct errors, the transformers had to be extraordinarily linear on their own. They're also the amplifier's fatal flaw: they are unique to this model, no longer available, and when they fail, the amplifier becomes virtually impossible to repair.
Dual-Mono Architecture with Separate Power Supplies
The Citation II is a dual-mono design with completely separate power supplies for each channel. That was unusual for a consumer amplifier in 1958, when most manufacturers shared a single supply between channels to cut costs. The fully regulated supply gave each channel clean, stable voltage regardless of what the other channel was doing, a critical factor in preserving stereo imaging and dynamic contrast.
Point-to-Point Wiring on Heavy-Gauge Steel
Inside, the Citation II is point-to-point wired on a heavy-gauge steel frame. There's no printed circuit board to crack or trace to lift, just hand-soldered connections between components. The front panel carries a single small power switch, and a rear-panel switch selects the output impedance match for 4, 8, or 16 ohm speakers. The amplifier consumes 300 watts and runs very hot. Owners warn that the output tube sockets are often cracked from decades of heat exposure.
Historical Context
The Citation II was introduced in 1958, designed by Stewart Hegeman, who had already made his name in high-fidelity circles. It sat at the top of the Citation series - Citation I preamp, Citation II power amp, Citation III tuner, Citation IV preamp - and was priced at $299 at launch, an extremely expensive amplifier for its day. Competing amplifiers at the time included the Marantz 8B, McIntosh MC-60, and Dynaco MK-III. The Citation II's combination of power, regulated supplies, and zero-feedback design set it apart.
The listening public and the press both backed up Hegeman's engineering. High Fidelity (May 1960, p.23) quoted C.G. McProud of Audio magazine, who wrote that "one listened through the amplifier system clear back to the original performance." The Citation II was designed to be the best amplifier money could buy, and for a few years in the late 1950s, it arguably was.
Collectibility & Value
The Citation II commands serious money today. Current market prices range from approximately $2,500 to $3,500 for a well-restored unit, depending on condition, and a fully restored example can fetch over $4,000 on eBay. Original units with their original transformers sell for $1,500 to $2,000, while restored units go for $3,000 and up.
The catch is the output transformers. They are unique to this model, no longer manufactured, and essentially unavailable except from donor units. When they fail, and they do fail, the amplifier becomes a parts source rather than a working component. Capacitors also dry out and need replacement, and the output tube sockets are frequently cracked from heat. Spare parts are essentially not available except from donor units, which makes service costly and increasingly difficult. Some owners complain that the amplifier runs very hot and is heavy to move. At 66 pounds, that's not an exaggeration.
The Citation II remains a grail piece for tube amplifier collectors. It has the no-negative-feedback design and the distinction of being the first KT88 amplifier, and it has a lot of physical presence.
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Related Models
- Harman Kardon 730 (1973-1979)
- Harman Kardon A-401
- Harman Kardon A 402
- Harman Kardon A660
- Harman Kardon Citation 16
- Eico 3150 (1967)
- Fisher CUSTOM-ELECTRA-I (K-14/K-15) (1957)
- Fisher CUSTOM-ELECTRA IV (E33/E44) (1960)
- Akai AM-2400 (1978)
- Akai AM-2600 (1977)