Infinity KAPPA-90
Floorstanding 3-way speaker system with dual 10-inch woofers and EMIT-B tweeter.
Overview
The Infinity KAPPA-90 is a floor-type, 3-way, 4-speaker bass reflex system, also described as a "Tall Boy" design. It features two 25.5 cm (10-inch) cone woofers for low-frequency reproduction, an 11.5 cm (4.5-inch) midrange driver, and a high-frequency EMIT-B tweeter — the same model used in Infinity’s flagship IRS-Epsilon. Designed to bring high-end IRS technology into a more accessible package, the KAPPA-90 supports bi-wiring and includes cleats for secure speaker cable connections.
Specifications
| Product type | floor-type speaker system, 3-Way, 4-Speaker, Bass Reflex System, Tall Boy Type |
| Units Used | For low band : 25.5 cm cone x2, For Medium Range : 11.5 cm Cone Type, For High Range : Special Type (EMIT-B) |
| Crossover | 250 Hz, 3.5 kHz |
| Sensitivity | 89dB/2.8V/1m |
| Input impedance | 6 Ω |
| Nominal Impedance | 6 Ω |
| Recommended amplifier output | 30W ~ 300W |
| External dimensions | Width 390x Height 1,230x Depth 380 mm |
| Weight | 40kg |
| Original price | ¥ 190,000 (1 unit, around 1999) |
Design
The KAPPA-90 uses two 25.5 cm APG Plus cone woofers with Kevlar and high-content carbon fiber for the low range. The 11.5 cm midrange driver features a non-magnetic magnesium chassis and low-mass rubber suspension. The high-frequency section uses the EMIT-B tweeter with a lightweight etched voice coil, waterproof stretch-resistant diaphragm, and neodymium magnets in a push-pull configuration. The crossover network incorporates high-grade polypropylene capacitors, unsaturated P-core inductors, and metal film resistors. The cabinet is trapezoidal, constructed from high-density, low-resonance particleboard, and finished in oak, with a black finish available as a made-to-order option. Bi-wiring is supported.
Context
The EMIT-B tweeter used in the KAPPA-90 is shared with the high-end IRS-Epsilon, positioning the Kappa series as a line that brings advanced Infinity IRS technology into a relatively more affordable form. The design philosophy emphasizes high fidelity and engineering quality from the flagship models in a practical floorstanding format.
Market
Refurbished pairs of Infinity KAPPA-90 speakers were available for around €1000 as of mid-2023. Common maintenance includes replacing foam surrounds and capacitors, with aftermarket foam repair kits available for the woofers.
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