Infinity 2000 II (Introduced 1968, production years 1975–1979 approximate)

At 33.5kg, it doesn’t just sit in the room—it commands it, radiating sound in every direction from a radical tweeter that defied convention.

Overview

The Infinity 2000 II wasn’t just another floor-standing speaker from the mid-70s—it was a statement. At a time when most high-end speakers still clung to conventional dome tweeters and modest dispersion, Infinity pushed forward with a radical idea: a 360-degree radiating high-frequency driver based on the Walsh principle. This wasn’t merely an aesthetic experiment; it was a deliberate engineering choice aimed at eliminating the directional limitations of traditional tweeters. Weighing in at 33.5kg, the 2000 II carried serious heft, both physically and sonically, and its presence in a listening room was undeniable. Marketed at $658 per pair (1977) or ¥199,000 per unit (around 1976), it occupied a premium tier, targeting audiophiles who wanted more than just fidelity—they wanted innovation.

Developed using technology refined in the earlier ServoStatik series, the 2000 II represented a transitional moment for Infinity, a company clearly in exploration mode. The four-way, four-driver configuration was ambitious, combining a 30 cm cone woofer for low frequencies, a 10 cm cone for midrange, a 2.5 cm dome for middle highs, and the standout Walsh Tweeter for the upper register. That tweeter, a vertically oscillating cylinder with a metal cone, projected sound in a full horizontal circle—360 degrees—while maintaining a focused 60-degree vertical dispersion. The goal was wide, even sound coverage without the "hot spot" effect common in forward-firing designs. Whether it succeeded depended on room placement and listener preference, but there was no denying its originality.

The crossover network leaned on a Butterworth alignment, chosen specifically for its ability to reproduce rectangular waves with minimal phase and time distortion. That’s a technical detail, but one with real-world consequences: A level control for the midrange allowed fine-tuning to suit room acoustics or personal taste—a thoughtful touch in an era when many speakers offered zero adjustability. The system demanded amplification: 25W RMS minimum per channel, with a maximum input rating of 250W, suggesting it could handle both modest receivers and high-powered separates.

Specifications

Key Features

360-Degree Walsh Tweeter with Vertical Cylinder Design

The defining feature of the 2000 II was its high-frequency driver—a Walsh Tweeter that operated as a vertically oscillating cylinder, radiating sound waves in a full 360-degree horizontal pattern. Unlike conventional tweeters that project sound forward, this design flooded the room with high frequencies, creating an immersive, diffuse soundfield. The metal cone structure contributed to its unique dispersion and tonal character, often described as open and natural. However, this omnidirectional behavior required careful placement; too close to walls or corners could result in excessive early reflections or bass buildup.

Butterworth Crossover Network for Time Alignment

Infinity implemented a Butterworth filter in the crossover section, a choice rooted in the pursuit of accurate transient response. The design aimed to enable “complete rectangular wave reproduction” by minimizing phase distortion and time difference errors between drivers. In practice, this translated to a speaker that could render complex musical passages with clarity and spatial precision. The crossover points—800 Hz, 4 kHz, and 10 kHz—were strategically placed to hand off frequencies smoothly across the four drivers. its topology reflected a serious commitment to time coherence, a concept still debated and valued among high-end audio enthusiasts.

Replaceable Top Plate with Dual Finish Options

One of the more unusual physical design choices was the removable top plate. The 2000 II came with two options: a black fabric top that matched the front grille and allowed high-frequency energy from the Walsh tweeter to escape unimpeded, and a hand-finished, oil-rubbed walnut top that provided a more traditional, furniture-grade aesthetic. This duality let owners match the speaker to their room’s decor—either as a technical object with a fabric cap or as a polished wooden column. The walnut version, while visually appealing, may have slightly altered the high-frequency dispersion due to the solid cover, though no measurements confirm the extent of the effect.

Historical Context

The Infinity 2000 II was introduced after the ServoStatik series, building on the company’s early reputation for technical innovation. It arrived during a period when Infinity was actively experimenting with driver technologies and enclosure designs, pushing the boundaries of what was considered practical in home audio. The model has been labeled “The Pioneer of Passive Radiator Technology” in some archival materials, though the 2000 II itself does not appear to incorporate a passive radiator in its documented design—this claim may conflate it with later Infinity models or reflect a broader interpretation of its engineering philosophy. Regardless, the 2000 II stood as a bold experiment in wide-dispersion sound, and helping establish Infinity as a brand unafraid to challenge norms.

Collectibility & Value

The Infinity 2000 II has developed a quiet but dedicated following among vintage audio collectors. A pair was recently listed on Facebook Marketplace for $475 in “Used - Good” condition, suggesting modest but stable demand. The most common failure point is aged foam surrounds on the woofer, a typical issue for speakers of this era. Replacement foam can degrade if improperly installed, leading to distorted bass or mechanical rubbing—hence the caution in online forums about “sloppy replacement of the surround material.” Fortunately, reputable restoration services like Millersound are reported to handle these repairs competently. Refurbished units with fresh surrounds, cleaned grilles, and refinished cabinets occasionally appear, sometimes with cosmetic work like vinyl removal and resurfacing with duratex.

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