Glensound GS‑TRRS Stereo Mobile Phone Audio Interface

Glensound GS-TRRS Stereo Mobile Phone Audio Interface connects a compatible phone’s analogue headset socket to broadcast equipment. Also documented as GS-MPI-TRRS, it converts the phone’s stereo headphone output to professional line-level audio while simultaneously feeding broadcast audio into the phone’s microphone circuit. Designed for journalists, newsrooms and radio studios, it combines accessible controls with a compact 1U rackmount enclosure.

Bidirectional Audio with Flexible Connections

The Glensound GS-TRRS balanced and unbalanced audio connections operate in parallel, allowing integration with professional mixing desks and equipment using unbalanced connections. Audio from the phone remains stereo; the left and right signals sent to the phone are summed to mono. A front-panel wiring selector accommodates the two headset wiring arrangements described by Glensound for Apple and Android phones. Compatibility depends on the handset’s analogue audio connection.

Front-Panel Level Control and Metering

Glensound GS-TRRS provides separate front-panel level controls for audio to and from the phone. A PPM-style meter displays the return level, helping operators accommodate recordings and sources with different playback levels. A rear-panel preset adjusts the microphone feed to suit the connected handset. Front and rear phone connections support temporary operator access or permanent studio wiring.

Phone Charging and Redundant Power

Four USB charging ports provide 5 V at up to 500 mA each, with two ports on the front and two on the rear. The interface operates from 100–240 V AC or an external ±12 V DC supply. Connecting both power sources provides supply redundancy. Aluminium construction and a 122 mm chassis depth support installation in equipment racks.

Basic Specifications

• Product designations: GS-TRRS / GS-MPI-TRRS.
• Phone interface: analogue four-pole 3.5 mm TRRS.
• Audio from phone: stereo.
• Audio to phone: mono sum of left and right.
• Maximum broadcast input: +22 dBu.
• Maximum line output: +24 dBu.
• Phone microphone feed: −17 to −57 dBu at unity front-panel gain.
• Frequency response: ±0.5 dB, 40 Hz–20 kHz.
• Charging: four 5 V, 500 mA USB ports.
• Power: 100–240 V AC or external ±12 V DC.
• Format: 19-inch, 1U; 122 mm deep.
• Published product weight: 1.16 kg.