K-Array Thunder KS4P I – Passive Dual 18-Inch Subwoofer (Black)

Product Overview

The K-Array Thunder KS4P I is a passive dual 18-inch subwoofer built for commercial AV systems that need deep, controlled low-frequency reinforcement without onboard amplification. As a high SPL passive subwoofer reaching 141 dB with extension down to 30 Hz, it anchors column array and line array systems in auditoriums, houses of worship, and large commercial venues. Its 4-ohm passive design and 2800 W peak power handling let integrators centralize amplification in the rack, simplifying installation subwoofer deployments and service access. This is the black finish; a white KS4PW I version is also available.

Product Description

At the core of the KS4P I are two long-excursion 18-inch neodymium magnet woofers with 3-inch voice coils, delivering response from 30 Hz to a crossover-dependent 150/450 Hz upper limit. Neodymium motors keep weight manageable for a dual-18 cabinet, and the birch plywood enclosure carries a polyurea coating that resists wear, impacts, and environmental stress in both touring and fixed installation duty. Two SpeakON NL4 connectors accept signal from external amplifiers over 2-wire or 4-wire cable and pass signal through to additional loudspeakers, streamlining daisy-chained installs. The cabinet pairs naturally with K-Array Kayman and other slim column elements — accessories such as the K-FOOT3 adapter let a Kayman column stand directly on top of the subwoofer for a compact full-range ground stack. When driven by K-Array Kommander amplification, DSP presets manage the low-pass crossover for accurate system tuning, and the Kommander platform offers control integration with Q-SYS, Crestron, Control4, and other commercial ecosystems. Removable rubber feet and black, white, or custom RAL finishes round out a cabinet designed for serious fixed installation work.

Key Features

• Dual 18-Inch Neodymium Woofers — Two long-excursion 18" drivers with 3" voice coils deliver extended bass response down to 30 Hz for full-bandwidth commercial systems.
• 141 dB Maximum SPL — High output capability keeps low-frequency impact strong and consistent even in large venues and high-energy program material.
• 2800 W Peak Power Handling at 4 Ohms — The passive 4-ohm design accepts high-output professional amplification and suits centralized amp-rack architectures.
• Dual SpeakON NL4 Connectivity — Two NL4 connectors accept 2-wire or 4-wire input and route signal through to additional loudspeakers, simplifying multi-cabinet installations.
• DSP-Managed Crossover — With matched K-Array processing, a preset-dependent low-pass at 150 Hz integrates the subwoofer accurately with Kayman and other column elements.
• Polyurea-Coated Birch Plywood Enclosure — The coated plywood cabinet resists scuffs, impacts, and environmental stress across years of installed or portable service.
• Lightweight for Its Class — Neodymium motors keep the dual-18 cabinet at 53.2 kg (117.3 lb), easing rigging and positioning during installation.
• Stack-Ready with K-Array Columns — Optional adapters allow Kayman, Kobra, and Python columns to mount directly on top for a compact full-range ground stack.

Typical Applications

• Auditoriums needing low-frequency extension beneath column or line array systems
• Houses of worship requiring full-range music reproduction with discreet main arrays
• Multi-purpose rooms hosting both speech events and high-energy program material
• All-hands rooms and large commercial meeting spaces with live music or video playback demands
• Broadcast studios requiring controlled, extended low-frequency monitoring reinforcement

Technical Specifications

Frequently Asked Questions

What amplifier should drive the Thunder KS4P I?

The KS4P I is passive, so it requires external amplification capable of high output into a 4-ohm load with 2800 W peak handling. K-Array Kommander amplifiers are the natural match because they include DSP presets that manage the low-pass crossover, but any professional amplifier with suitable power and processing can be used.

How does it connect within a larger system?

Two SpeakON NL4 connectors accept amplifier signal over 2-wire or 4-wire cable and allow signal routing through to other loudspeakers, so daisy-chained subwoofer and column configurations wire cleanly without extra distribution hardware.

Which K-Array speakers pair with this subwoofer?

The KS4P I is commonly deployed beneath K-Array column elements such as the Kayman KY102, with optional adapters that let a column stand directly on top of the cabinet for a compact ground stack.

Is the KS4P I suitable for fixed installation?

Yes. The polyurea-coated birch plywood enclosure, removable rubber feet, and available custom RAL finishes are designed for permanent commercial installations as well as portable production use, and accessories support flying the cabinet where designs require it.

Does it integrate with AV control systems?

When driven by K-Array Kommander electronics, the system gains control integration with Q-SYS, Crestron, Crestron Home, Control4, Symetrix, and other platforms, plus Dante networking on supported amplifiers for IP-based commercial AV integration.

What warranty applies?

K-Array products carry a 5-year manufacturer warranty, supported by Creation Networks as an authorized dealer. Explore matching elements in our K-Array collection.