Passive direct box Mackie MDB-2P Black Bass guitar Digital piano Guitar Synthesizer

The Mackie MDB-2P is a passive direct box designed for bass guitar, digital piano, guitar and synthesizer applications. It provides a wide frequency response from 20 to 20,000 Hz, a high input impedance (140,000 Ω) and a standard low output impedance (400 Ω) to match balanced mixing console inputs. The compact metal chassis (86 mm × 147 mm × 38 mm) combines durable construction with portability for stage and studio use.

Advantages

The passive design requires no power source while offering reliable signal isolation and low-noise performance. Thick steel construction, impact-resistant corners and long-wearing jacks increase mechanical durability for regular transport and live use. The MDB-2P provides transparent analog circuitry that preserves the natural tone of basses, electric guitars, digital pianos and synths when connecting to PA or recording interfaces.

Suitable for

• Bass guitar direct connection to mixers or recorders
• Digital piano or keyboard DI feed for live sound
• Electric guitar to front-of-house or studio console
• Synthesizer outputs requiring balanced lines and ground isolation

Key specifications

• Frequency response: 20 – 20,000 Hz
• Input impedance: 140,000 Ω
• Output impedance: 400 Ω (balanced)
• Passive (no battery or phantom power required)
• Compact metal chassis: width 86 mm, depth 147 mm, height 38 mm
• Durable construction with impact-resistant corners and long-life jacks

How to use

Connect the instrument’s output to the MDB-2P input jack, then run a balanced XLR output from the MDB-2P to the mixer or recording interface. For guitars and basses, use the direct input and engage any on-board instrument controls as needed. For keyboards and synthesizers, route the main output into the DI to provide a balanced, low-noise signal to FOH or multitrack recorders. No power is required for normal operation.

Usage recommendations

Place the direct box near the instrument source to minimize unbalanced cable runs. When connecting to systems with ground-loop hum, use the console’s ground-lift option if available. Inspect jacks and cables regularly and store the unit in protective gear during transport to maintain long-term reliability.