Infinity RS-6 (1982?)

A floorstanding statement from Infinity’s Kappa era—sealed, refined, and built to impress with EMIT tweeter magic and serious low-end for its time

Overview

The Infinity RS-6 wasn’t just another box in the speaker lineup—it was a flagship statement. Marketed as the top model in the New RS series and part of the prestigious Kappa family, this tall, sealed floorstander carried the weight of Infinity’s engineering ambitions in the mid-1980s. Known variously as the RS-6, RS-6 Kappa, RS-6001, or RS-6B, it’s one of those models where the naming gets murky fast—owners report seeing all these variants in the wild, though whether they reflect revisions, regional differences, or marketing tweaks remains unclear. What isn’t debatable is the build: a 3-way, floor-standing “Tall Boy” design that traded ported bass for the tighter, more controlled response of an airtight sealed enclosure. At a time when many were chasing boom, Infinity went the other way—precision, extension, and coherence.

This was high-end stuff. The RS-6 wore its premium status on its sleeve, from the use of Monster cable inside to polypropylene capacitors like Solen in the crossover—components audiophiles still chase today. It was built to be paired with serious amplification, handle up to 150 watts, and deliver a frequency response that stretched all the way to 45 kHz, well beyond human hearing but hinting at a design optimized for transient accuracy and air. Whether you’re chasing that elusive “live” sound or just want a vintage speaker that doesn’t lean on ported bass to fake it, the RS-6 was engineered to perform. According to available documentation, the RS-6B variant was introduced in 1984 and discontinued in 1986, placing the model firmly in the heart of the Kappa era.

Key Features

EMIT-K Tweeter: The Crown Jewel

The star of the show is the EMIT-K (Electro Magnetic Induction Tweeter) with its Kapton diaphragm and neodymium magnet in a push-pull configuration. This isn’t your average dome tweeter—EMIT technology was Infinity’s answer to the limitations of traditional soft domes, aiming for lower distortion and faster transient response. The push-pull design cancels out magnetic non-linearities, and the use of neodymium keeps the motor structure compact and powerful. The result? A tweeter that’s detailed without being edgy, extended without fatigue. Owners report the highs as “great,” with a sense of openness that doesn’t scream “vintage harshness.” Some units were later restored with Polydome K tweeters, suggesting that while durable, the original EMIT-K units may degrade or require replacement over decades of use.

Midrange Clarity via Dome Design

Sandwiched between the woofer and tweeter is a dome midrange driver using a polypropylene/graphite composite diaphragm. This isn’t a cone—you’re getting the dispersion benefits of a dome with the stiffness of a reinforced material. The crossover hits at 800 Hz, handing off vocals and instruments to a driver optimized for clarity. Combined with the sealed cabinet, this setup avoids the colorations that can plague ported mid-bass regions. The midrange is described as “very good,” with a natural presence that keeps voices and acoustic instruments front and center. No shout, no dip—just honest reproduction.

IMG Woofer: Stiff, Light, and Fast

The 8-inch (20cm) woofer uses an IMG (Injection Mold Graphite) diaphragm—polypropylene reinforced with graphite fiber. This material combo delivers stiffness without adding mass, which means the cone can start and stop quickly, reducing smearing. In a sealed cabinet tuned for accuracy rather than bass quantity, this is exactly what you want. Despite being “only” an 8-inch driver, owners note it “goes pretty low,” likely due to the cabinet tuning and driver control. The frequency response reportedly extends down to 39 Hz, which is impressive for a non-ported design of this size. Some versions, such as the RS-6/B, used polypropylene cones and dual voice coil 8-inch woofers rated at 4 ohms, suggesting variations in bass driver implementation across the RS-6 family.

Sealed Cabinet with Round Baffle

Infinity opted for a sealed (airtight) enclosure, which trades efficiency for tighter, more time-aligned bass. The cabinet is built from high-density particleboard, and the front baffle is rounded to reduce edge diffraction—something you don’t see often in speakers of this era. That round baffle helps smooth the off-axis response, contributing to a more coherent soundstage. No rear port means you can place these closer to walls without worrying about boundary reinforcement messing with the tuning. It’s a purist’s choice, and it shows.

High-End Internal Execution

Inside, the RS-6 doesn’t cut corners. The crossover uses polypropylene capacitors—Solen being one example noted—and “optimal Q” inductors, suggesting careful attention to filter behavior. The internal wiring is Monster cable, which, love it or hate it, was a premium choice at the time and indicates Infinity wasn’t skimping on signal path integrity. There’s also a level control, likely for the tweeter or midrange, allowing owners to fine-tune the voicing to their room or preference—a nice touch for a speaker of this class. However, the crossover for the RS-6/B variant (part number #716-0347) is now listed as NLA (“No Longer Available”), making repairs or replacements challenging for current owners.

Historical Context

The RS-6 emerged during a period when Infinity was consolidating its reputation for high-performance, technically advanced loudspeakers. As the flagship of the New RS series and a member of the Kappa family, it represented the company’s commitment to accuracy and innovation. The sealed design contrasted with the ported trends of the time, appealing to listeners who valued timing and clarity over raw output. HiFi-Stereo (November 1983, p.47) noted that the three drivers were mounted in a vertical line and that the speaker could be operated vertically or mounted horizontally on a shelf, offering some flexibility in placement despite its floorstanding stature.

Collectibility & Value

The RS-6 isn’t a unicorn, but it’s not common. Pairs show up on the used market from time to time, with prices ranging from €125 all the way up to €650 or $399, depending on condition, finish (natural oak vs. wood-grain print), and whether they’ve been serviced. The higher end of that range likely reflects well-maintained or restored units—especially those with recapped crossovers or refoamed woofers. Fully restored RS-6 Kappa models have listed at $699 on Reverb, indicating strong demand among vintage audio enthusiasts.

Maintenance is pretty predictable for a speaker this age. The 8-inch woofer surrounds may need refoaming, a standard procedure that can restore punch and eliminate rattles—YouTube repair videos confirm this as a common need for the 1984 RS-6/B. The crossover capacitors, while high-quality to begin with, are still decades old—owners report that recapping can sometimes improve performance, bringing back clarity and dynamics. The level controls (if present) may need cleaning if they’ve gotten noisy over time. Given that the crossover for the RS-6/B is now NLA, sourcing replacements or building equivalents may be necessary for long-term ownership.

There’s also an optional stand, the RS-6PED, sold separately—worth tracking down if you want to position them correctly and avoid floor reflections muddying the bass.

Despite the lack of definitive differentiation between the RS-6, RS-6B, and RS-6001, owners are enthusiastic. One reports loving the sound in their living room; another says they “sound really good” with strong bass, excellent midrange, and a top end that delivers. That’s high praise from real-world use—not marketing copy.