Infinity Quantum 5 (Late 1970s)
A three-way loudspeaker system featuring EMIT tweeters and Polydome midrange drivers, known for high-fidelity audio reproduction.
Overview
The Infinity Quantum 5 is a vintage loudspeaker system introduced in the late 1970s by Infinity. Designed as a three-way system, it features a 12” Watkins woofer, an EMIT (Electromagnetic Induction Tweeter), and a Polydome midrange driver. The speaker uses a well-damped enclosure with quality wood veneers to minimize resonance and deliver accurate sound. It was engineered for low distortion and high efficiency, capable of detailed, dynamic audio across a wide range of genres.
Design
The Quantum 5 uses a three-way driver configuration with a dual-drive woofer setup and an active crossover to ensure optimal phase alignment between drivers. The cabinet is solidly built with high-quality wood veneers, and the drivers are mounted in a well-damped enclosure to reduce unwanted resonance. The system includes 700μF capacitors for the woofer section and features the distinctive EMIT tweeter and Polydome midrange driver, both designed for extended high-frequency response and clarity.
Context
Introduced in the late 1970s, the Quantum 5 quickly gained a reputation for accurate sound reproduction and robust construction. It became known among audiophiles for its crisp highs, punchy bass, and overall exceptional performance, with some users noting its ability to handle demanding audio with ease.
Market
Current asking prices for the Infinity Quantum 5 range from $360 to $700, depending on condition. Common maintenance issues include deteriorating foam surrounds on the woofers, failed EMIT tweeters, degraded crossover components such as capacitors, and loose or corroded wiring. Replacement parts, including 12” Watkins woofers and EMIT tweeters, are occasionally available on the secondary market.
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