Mackie MDB-1P Passive Direct Box

Passive Direct Box

The Mackie MDB-1P is a passive direct box designed to connect a single instrument such as a guitar, bass, or keyboard to a microphone preamp for musicians and audio engineers in recording sessions, houses of worship, and live stage applications. It converts a high-impedance, instrument-level signal via its 1/4" TS unbalanced input to a low-impedance, mic-level output via its balanced XLR 3-pin jack. A 1/4" thru jack allows simultaneous connection to an amplifier or pedalboard.

A -15 dB pad reduces the input level to prevent distortion when using a high-gain source, and the ground-lift switch inhibits hum caused by ground loops. Due to its passive design, the MDB-1P requires no batteries or power supply. A sturdy steel chassis enables confident use in the studio or on the road.

Features:

• Connect an instrument such as a guitar, bass, or keyboard to a microphone preamp
• Converts a high-impedance, unbalanced 1/4" input to a low-impedance, balanced XLR mic-level output
• 1/4" thru jack for routing to an amplifier
• -15 dB pad prevents overloading when accepting signal from a loud source
• Ground-lift switch minimizes hum
• Passive design requires no batteries or power supply

Specifications:

• Type: Passive
• Input Connections: 1 x 1/4" TS unbalanced
• Output Connectors: 1 x 1/4" TS unbalanced
• 1 x XLR 3-pin balanced
• Input Impedance: 140 kOhms unbalanced
• Output Impedance: 400 Ohms unbalanced
• Impedance Ratio: 350:1
• Pad: -15 dB
• High-Pass Filter: None
• Controls: Pad
• Ground-lift switch
• Frequency Response: 20 Hz to 20 kHz (±0.2 dB)
• Signal to Noise Ratio: Not specified by manufacturer
• Dynamic Range: 128 dB
• Total Harmonic Distortion: 0.002% from 1 kHz
• Power Requirement: None
• Current: N/A
• Construction Material: Heavy-gauge steel chassis
• Dimensions (H x W x D): 1.5 x 3.4 x 5.8" / 38 x 86 x 147 mm
• Weight: 0.8 lb / 0.4 kg