RDL STD-150 150 Ohm Passive Balanced Audio Combiner / Divider 4-Channel RF Filtered

Description

The STD-150 is a passive resistive branching audio module designed to combine or split balanced audio lines. It provides four channels labeled A through D which may be used as inputs or outputs interchangeably. The unit includes RF filtering on each channel to reduce radio frequency interference and preserve audio clarity.

The module operates at 150 Ohm impedance and supports combining stereo signals to mono or splitting mono to multiple inputs. Each channel is balanced and includes resistive network topology providing predictable 3dB insertion loss. Channel isolation measures approximately 3 dB, so isolated mixing or distribution should use dedicated mixers or distribution amplifiers when greater isolation is needed.

Technical performance includes a maximum signal input level of +22 dBu and passive operation that requires no external power. The module is a passive device so it introduces a nominal 3dB insertion loss per branch. RF filtering on each channel helps maintain signal integrity in RF-rich environments, and all I/O are balanced for compatibility with professional audio lines.

Connectivity is simple and direct: any of the four balanced connectors can serve as an input or output to allow combining multiple microphone outputs or feeding a mono source to stereo inputs. The resistive network permits configurations such as 1-in to 3-out, 2-in to 2-out, or 3-in to 1-out depending on system needs. This flexibility makes the STD-150 compatible with a wide range of consoles, amplifiers, and line-level equipment.

Typical applications include broadcast patching, FOH bridging, temporary event audio distribution, and combining microphone signals to a single amplifier input where shorting switches are used. The module is well suited for rack, stick-on, or concealed installations where compact passive combining or splitting is required. It is particularly useful when RF filtering and balanced connectivity are needed without active electronics.

The STD-150 is supplied in compact packaging suitable for field or permanent installations and requires no power or calibration. Its passive construction offers high reliability and long service life with no maintenance overhead. The build is compact and unobtrusive, making it easy to integrate into existing audio infrastructure.