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Sound Lab SDB-40 Direct Box main image

Sound Lab SDB-40 Direct Box

Sound Lab SDB-40 Direct Box

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Page last updated Aug 10, 2025

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Description

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The Sound Lab SDB-40 Direct Box is an essential tool for musicians and audio engineers looking to maintain pristine audio quality during live performances and studio sessions. Designed to convert high-impedance, unbalanced signals into low-impedance, balanced signals, this direct box ensures your sound remains crisp and interference-free over long cables. Featuring transformer-balanced output, the SDB-40 provides superior noise reduction and signal integrity, making it ideal for both electric instruments and keyboard setups.

With its rugged metal chassis, the Sound Lab SDB-40 is built to withstand the rigors of the road. It includes a ground lift switch to eliminate hum caused by ground loops, a must-have for any professional setup. The passive design means no need for external power, offering a hassle-free experience wherever you play. Whether you're connecting guitars, basses, or keyboards, the SDB-40 guarantees your tone remains true to its source.

Key Features:

Transformer-balanced output for noise reduction
Converts high-impedance, unbalanced signals to low-impedance, balanced signals
Passive design, no external power required
Rugged metal chassis for durability
Ground lift switch to eliminate hum
Ideal for electric instruments and keyboards

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