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R400b

Name: KEF R400b
Brand: KEF

KEF

R Series Series

LoudspeakersSubwoofersPowered LoudspeakersDiscontinued

Estimated price (community-sourced)

$650

About the R400b

The KEF R400b is a powered subwoofer featuring twin 9-inch bass drivers, each powered by a 250W class-D amplifier, totaling 500W of power. It is designed to deliver deep bass with a frequency response of 26Hz to 140Hz (-6dB) and a maximum output of 111dB. The subwoofer includes a variable fourth-order low-pass filter adjustable from 40Hz to 140Hz, allowing for precise integration with other speakers. It also features phase adjustment (0 or 180 degrees) and an equalization switch offering 0, 6, or 12dB of boost around the 40Hz region. The R400b is available in high-gloss finishes of black or white and is built with a sealed design to minimize vibration.

Specifications

Key Specifications

Sensitivity: 111 dB

Frequency: 26-140 Hz

Full structured specifications are available to members.

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