RDL STD-600 600 Ohm Passive Balanced Audio Divider / Combiner 4-Channel RF Filtered

Description

The STD-600 is a passive 600 Ohm balanced audio divider and combiner designed for professional audio installations. It provides four balanced channels that may each serve as an input or an output, enabling flexible routing of analog signals. The unit includes RF filtering on every channel to reduce interference and protect signal integrity.

Each channel of the STD-600 uses a resistive branching network to combine or split signals while maintaining balanced line operation. The module supports combining stereo into mono, splitting mono to multiple inputs, and summing microphone outputs into a single amplifier input. All inputs and outputs are balanced to minimize noise and preserve common-mode rejection.

Technically, the STD-600 operates at 600 O nominal impedance and exhibits a 3 dB insertion loss when splitting or combining signals. Channel-to-channel isolation is approximately 3 dB, so isolation-critical applications should use active mixers or distribution amplifiers. The module accepts signal levels up to +22 dBu without degradation.

Connectivity is straightforward: four balanced channels labeled A through D that can be used in any input/output combination. RF filtering is applied to each channel to suppress radio-frequency interference on the audio lines. The passive design requires no external power and installs simply inline with balanced cabling.

Common applications include summing stereo feeds to mono amplifier inputs, distributing a mono source to multiple stereo inputs, and combining multiple microphone lines where controlled summing is required. The RF filtering also makes the STD-600 suitable for environments with potential radio or RF noise. Its compact size allows placement near equipment or behind panels where space is limited.

The STD-600 is compact and delivered in a small cardboard package for easy deployment. As a passive STICK-ON style module it installs without power and adds minimal complexity to an audio system. The mechanical simplicity contributes to long-term reliability and low maintenance in professional AV installations.