Infinity SERVO-STATIK-1 (1968): Pioneering Electrostatic Excellence

In the late 1960s, most loudspeakers used conventional dynamic drivers - paper cones and magnetic motors. A few engineers wanted something clearer and more accurate. Two of them were Arnie Nudell and Cary Christie, Southern California engineers whose garage experiments led to Infinity Systems and the SERVO-STATIK-1, introduced in 1968.

The Infinity SERVO-STATIK-1 is not a receiver, amplifier, or turntable, but it has a place in vintage audio history anyway. It was one of the first commercially available servo-controlled electrostatic loudspeakers, a big departure from traditional speaker design, and it set the stage for later electrostatic and servo-assisted technologies.

A Revolutionary Concept

The SERVO-STATIK-1 was not a full-range electrostatic like the later Quad ESL or the Acoustat models. Instead, it combined two technologies in one system:

A large electrostatic panel for midrange and high-frequency reproduction
A servo-controlled dynamic woofer for bass response

The electrostatic panel gave the speed, low distortion, and near-perfect dispersion that electrostatics are prized for. The bass section used a conventional 12-inch woofer, with one twist: it was servo-controlled. A feedback loop monitored the actual movement of the cone and corrected errors in real time.

The servo was one of the SERVO-STATIK-1's most significant innovations. The amplifier compared the input signal to the actual cone position (via a sensing coil) and adjusted the drive signal to minimize distortion and improve transient response. The result was bass that was tighter, more accurate, and more articulate than almost any other speaker of its time.

Technical Specifications

Specification	Detail
Model	SERVO-STATIK-1
Manufacturer	Infinity Systems
Year Introduced	1968
Type	Hybrid electrostatic/dynamic loudspeaker
Frequency Response	35 Hz – 18 kHz (±3 dB)
Crossover Type	Passive, 500 Hz
Electrostatic Panel	Large-area push-pull electrostatic transducer
Bass Driver	12-inch dynamic woofer with servo feedback
Servo System	Closed-loop feedback via sensing coil
Impedance	Not applicable (active system with proprietary amp)
Power Handling	Not applicable (requires dedicated servo amplifier)
Sensitivity	~86 dB (1W/1m)
Dimensions (H×W×D)	Approx. 72" × 24" × 20"
Weight	~120 lbs each
Crossover Frequency	500 Hz
Recommended Amplifier	Infinity Servo Statik Amplifier (matching active unit)

The SERVO-STATIK-1 was not a passive speaker in the conventional sense. It required a dedicated servo amplifier—a separate chassis that housed both the power amp for the woofer and the high-voltage supply for the electrostatic panel. This amplifier also contained the feedback circuitry essential for the servo operation. As such, the system was sold as a matched pair: speakers plus control amplifier.

Sound Characteristics and Performance

Listeners of the day were struck by the ethereal clarity of the electrostatic midrange and highs. Voices and acoustic instruments seemed to float in space with uncanny realism. The panel's dipole radiation pattern created a wide, open soundstage with excellent depth and imaging precision.

The bass was not as deep or powerful as a modern subwoofer, but it was tight and controlled for the era. The servo feedback drastically reduced cone excursion errors, which cut the "one-note" bloat common in many 1960s bass systems. When properly set up, the SERVO-STATIK-1 delivered bass articulation that few speakers could match, especially in small to medium-sized rooms.

Critics and early adopters praised the low distortion, especially in the mid-bass region. With no port noise, no cabinet resonances, and no dynamic driver colorations, the sound was clean and transparent, and it appealed to purists and audiophiles alike.

Notable Features and Innovations

The SERVO-STATIK-1 was packed with forward-thinking engineering:

Servo-Controlled Bass: The first commercially successful use of real-time cone position feedback in a consumer loudspeaker.
Push-Pull Electrostatic Panel: Reduced even-order harmonic distortion and improved linearity.
Active Crossover and Amplification: Allowed precise tuning and optimization of each driver.
Modular Design: The system was engineered for serviceability and upgrades—a rarity in the 1960s.

The SERVO-STATIK-1 proved that exotic, laboratory-grade audio technologies could be commercialized. It helped establish Infinity as a serious player in high-end audio and paved the way for later models like the Servo Statik 3 and the IRS (Infinity Reference Standard).

Common Issues and Maintenance

Today, the SERVO-STATIK-1 is a rare and prized collector's item. Owning one comes with challenges:

Electrostatic Panel Degradation: Over time, the stators and diaphragms can deteriorate. Moisture, dust, and high voltage stress can lead to arcing or loss of tension in the diaphragm.
Capacitor Aging: The high-voltage power supply and servo feedback circuits rely on capacitors that may have dried out or failed after 50+ years.
Woofer Surrounds: The foam surrounds on the 12-inch drivers are likely perished and will need replacement.
Amplifier Reliability: The original servo amplifiers contain discrete transistors and electrolytic capacitors that may require recapping or full restoration.

Original parts are hard to find, but a small community of vintage Infinity enthusiasts and restorers exists. Some technicians specialize in refurbishing these systems, often replacing foam, recapping power supplies, and even rebuilding electrostatic panels using modern materials.

The panel runs on high voltage, up to 5,000 volts, so only experienced technicians should service these speakers.

Current Market Value and Collectibility

The SERVO-STATIK-1 is extremely rare on the vintage market. Complete, working systems show up only occasionally on audiophile forums, eBay, or specialized vintage audio dealers. When they do, prices can range from $2,500 to $5,000 or more, depending on condition and completeness.

Collectors value the SERVO-STATIK-1 for its sound and for its historical significance. It was an early experiment combining electrostatic and servo technologies, a precursor to modern active speakers and digital correction systems. For museums, audio historians, and serious vintage enthusiasts, it's a landmark design.

Restored units with upgraded components (such as modern foam, improved caps, or reinforced panels) are often more desirable than untouched originals, which may be non-functional.

Conclusion: A Legacy of Innovation

The Infinity SERVO-STATIK-1 (1968) was never a mass-market product. It was expensive, complex, and demanding of care. It demonstrated that feedback control could improve loudspeaker performance, a concept that later influenced Infinity's own products and the development of active speakers, DSP correction, and modern servo-subwoofers.

More than just a speaker, the SERVO-STATIK-1 was a statement of intent—a declaration that high fidelity could be achieved through innovation, not just incremental refinement. It embodied the spirit of the late 1960s: bold, experimental, and unafraid to challenge convention.

Today, the SERVO-STATIK-1 stands as a monument to analog ingenuity—a rare fusion of electrostatic elegance and servo precision that continues to inspire audiophiles and engineers alike. For those lucky enough to hear one in good condition, it’s not just a trip back in time—it’s a glimpse into the future of sound, as imagined over fifty years ago.

Similar items on eBay

No exact Infinity SERVO-STATIK-1 listings are live right now — these searches show current Infinity and similar vintage audio gear on eBay:

Search Infinity SERVO-STATIK-1 on eBay Browse Infinity audio gear on eBay

As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.