Thunder-KS4P I

The Thunder-KS4P I is a passive subwoofer featuring 2x long excursion 18” neodimium magnet woofer with 3” voice coil. The Thunder-KS4P I features 2x SpeakON NL4 connectors that allow to input the signals from external active systems or amplifiers, with either a 2-wire or a 4-wire cable, as well as route the signal to other loudspeakers.



Ultra-light, high power subwoofers



  • Type:  

    Passive subwoofer

  • Transducers:  

    2 x 18" neodymium magnet woofer

  • Frequency Response:  

    30 Hz – 150/450 Hz (-6 dB) crossover dependant

  • Crossover:  

    DSP-controlled, Low Pass @ 150 Hz, preset dependant

  • Max SPL:  


  • Coverage:  


  • Rated Power:  

    2800W peak

  • Connectors:  

    2 x Speakon NL4

  • Nominal Impedance:  


Handling and Finishes

  • Dimensions (W x H x D):  

    1106 x 500 x 580 mm
    (43.5 x 19.7 x 22.8 in)

  • Weight:  

    53,2 kg (117.3 lb)

  • Material:  

    Polyurea coated birch plywood

  • Colors:  

    Black/White/Custom RAL


  • IP Rating:  


  • (1) With dedicated preset
  • (2) Maximum SPL is calculated using a signal with crest factor 4 (12dB) measured at 1 m.
  • (3) Included 17 mm (0.7 in) removable rubber feet
  • (4) In case of permament, long lasting installation in critical environments (swimming pools, beaches, yachts..), we recommend to further protect the subwoofer. Contact K-array directly to discuss best protection practices.
  • Passive loudspeakers requires dedicated preset loaded on board of K-array amplifiers.

  • New materials and design are introduced into existing products without previous notice.


Thunder-KS4P I Datasheet

ver 1.0

CE Declaration of Conformity

KS4P Layout

Amp-to-speaker matching table

Thunder KS MK1 Subwoofers User's Manual

Thunder-KS4P I BIM

KS MK1 Subwoofer Quick Guide

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