Passive DI Box Omnitronic LH-061 PRO — 2-channel direct box for balanced outputs

The Omnitronic LH-061 PRO is a passive 2-channel DI box engineered to convert unbalanced instrument or line-level signals into balanced outputs for long cable runs and stage or studio integration. Its two independent channels accept guitar, bass, keyboard or other line sources and provide balanced XLR outputs to connect directly to mixers, audio interfaces or PA systems. The passive design requires no external power while offering galvanic isolation and a ground lift switch to reduce hum and interference in live and recording environments.

Advantages

The LH-061 PRO combines a compact, rugged metal housing with transformer-based passive circuitry to ensure reliable signal integrity and durability in demanding conditions. With two separate channels, each featuring input and parallel output connections, the unit allows instrument-level sources to feed both an amplifier and a balanced mixer input simultaneously. The ground lift function helps eliminate ground loop noise, and the passive transformers preserve tonal character without introducing active electronics that require power.

Suitable for

• Connecting electric guitars or basses to a mixer or PA for live performance
• Integrating keyboards and synths with long cable runs to front-of-house
• Feeding line-level devices (effects boxes, drum machines) into recording interfaces
• Stage setups requiring ground lift to reduce hum and interference

Key specifications

• Channels: 2 independent passive channels
• Inputs: Unbalanced instrument/line inputs with parallel (thru) outputs
• Outputs: Balanced XLR outputs suitable for long cable runs
• Ground isolation: Ground lift switch per unit to address hum
• Construction: Rugged metal chassis for stage and studio use
• Power: Passive operation — no external power required

How to use

Connect the unbalanced instrument or line output (guitar, bass, keyboard or line device) to one of the LH-061 PRO inputs. If you need to send the unbalanced signal to an amplifier at stage level, use the parallel (thru) output to feed the amp while the balanced XLR output goes to the mixer or PA. Set the ground lift switch if you encounter hum or buzzing caused by ground loops. Because the unit is passive, no power supply or batteries are needed; simply route the balanced XLR output to the mixer preamp or interface input and adjust levels on the receiving device.

Usage recommendations

For best results, place the DI box close to the instrument or source to minimize unbalanced cable length, and use quality XLR cables for the balanced runs. Engage the ground lift only when necessary to address noise; if signal level is low, ensure the receiving preamp provides sufficient gain and check impedance compatibility between the source and the DI box.