K-Array Thunder KS2 I – Compact Self-Powered 18" Subwoofer

Product Overview

The K-Array Thunder KS2 I subwoofer is a compact self-powered 18" subwoofer with onboard DSP, built for commercial AV installation in rooms where space and weight are constrained. At 37.6 kg it is the lightest self-powered model in the Thunder KS I line, yet its 18" neodymium woofer and four-channel 1500W Class D amplifier deliver 137 dB peak SPL with response down to 35 Hz. Its amplifier power outputs drive passive K-array loudspeakers directly, so one KS2 I can serve as the powered core of a complete system. It fits integrators specifying a DSP subwoofer for house of worship installation, training rooms, or mid-size multi-purpose spaces.

Product Description

The Thunder KS2 I packs an 18" neodymium magnet woofer and a 4x 1500W @ 4 ohm Class D amplifier module into a bass reflex enclosure measuring just 650 x 500 x 580 mm. The feature that sets the Thunder line apart for system designers is its audio power outputs: two SpeakON NL4 connectors let the KS2 I drive passive K-array midrange loudspeakers and passive subwoofers from its own amplifier channels, removing the need for a separate amplifier in many small and mid-size commercial deployments. Onboard DSP — running on the embedded osKar operating system with a quad-core 1.5 GHz processor — supplies a freely assignable routing matrix, three-band parametric input EQ, eight-band parametric output filters, dynamic limiters, and up to 230 ms of channel delay.

Connectivity includes two XLR inputs that accept balanced analog or AES3 digital signals, matching link outputs for chaining, an RJ45 port for wired control through K-Framework3 software, and Wi-Fi access to DSP parameters via the K-array Connect mobile app. The Finnish birch plywood cabinet wears a rugged polyurea coating and carries an IP53 rating, ready for both fixed installation and portable commercial use. This black model is also available in white as the Thunder KS2W I, and compatible passive satellites are in our K-array collection.

Key Features

• Lightweight 18" Subwoofer — At 37.6 kg in a 650 mm wide cabinet, the KS2 I is the easiest Thunder KS I model to install, transport, and position in finished spaces.
• 137 dB Peak SPL with 35 Hz Extension — The 18" neodymium woofer covers the low-frequency needs of mid-size commercial rooms from a single compact enclosure.
• 4x 1500W Class D Amplification — The built-in four-channel amplifier delivers 1500W per channel at 4 ohms for the subwoofer and connected passive speakers.
• Power Outputs for Passive K-array Speakers — Two SpeakON NL4 outputs drive passive K-array satellite and subwoofer elements, letting one KS2 I power an entire room.
• Onboard DSP with Routing Matrix — Integrated processing includes parametric EQ, selectable IIR filters, dynamic limiters, signal routing, and up to 230 ms of delay per channel.
• Analog and AES3 Digital I/O — Dual XLR inputs and link outputs accept balanced analog or AES3 digital signals for flexible system integration.
• Ethernet and App Control — K-Framework3 software manages units over wired LAN while the K-array Connect app provides wireless commissioning access.
• IP53-Rated Polyurea Cabinet — The coated Finnish birch plywood enclosure resists dust and water spray in demanding commercial environments.
• Black, White, or Custom RAL Finish — Factory finish options allow the cabinet to match the design language of the installed space.

Typical Applications

• House of worship systems where one compact unit powers passive satellites
• Training rooms and commercial meeting spaces with music or program playback
• Multi-purpose rooms hosting presentations, events, and background audio
• All-hands rooms requiring full-range reinforcement without an amplifier rack
• Broadcast studio environments needing compact low-frequency support

Technical Specifications

Frequently Asked Questions

Which passive K-array speakers can the Thunder KS2 I power?

The KS2 I's four 1500W amplifier channels and SpeakON NL4 outputs drive passive K-array midrange loudspeakers and passive subwoofers using dedicated presets loaded onboard. Our team can confirm channel loading against K-array's amp-to-speaker matching table for your specific satellite selection.

Is the KS2 I powerful enough for my room?

With 137 dB peak SPL and 35 Hz extension, the KS2 I covers most training rooms, worship spaces, and mid-size multi-purpose rooms. For larger auditoriums, step up to the 21" KS3 I (139 dB) or dual-18" KS4 I (141 dB).

Can the KS2 I eliminate a separate amplifier and DSP in my design?

In many small and mid-size systems, yes. With 4x 1500W of amplification plus a routing matrix, parametric EQ, limiters, and delay onboard, one KS2 I powers and processes a complete satellite-plus-subwoofer system without an external rack.

How does the KS2 I integrate with commercial control systems?

Configuration runs through K-Framework3 software over wired Ethernet or the K-array Connect app over Wi-Fi, and K-array publishes plugins for Q-SYS, Crestron, Control4, and other control platforms.

Can a satellite speaker be mounted on top of the KS2 I?

Yes. The cabinet includes an M20 pole mount compatible with the K-POLE2 extendable pole, allowing a K-array satellite to be positioned directly above the subwoofer for a compact full-range column.

What warranty and support are included?

K-array products are covered by the manufacturer's five-year warranty, and Creation Networks provides pre-sale system design assistance and post-sale integration support.