Thor Broadcast F-2A-XLR-B-TxRx-RM XLR Audio over Fiber | Bi-Directional Balanced Audio | 20 km Single-Mode Links

Balanced XLR Audio over Fiber

Broadcast, live event and installed AV work runs on balanced XLR audio, and that audio often has to travel farther than copper can carry it cleanly. The Thor F-2A-XLR-B-TxRx-RM moves balanced analog audio over fiber on standard three-pin connectors, as a matched transmitter and receiver. This particular rack-mount model is bi-directional, so send and return paths share a single strand instead of occupying two separate fiber runs.

Wavelength Plan and Audio Quality

Uni-directional models work at 1310 nm, while bi-directional versions combine 1310 and 1550 nm on the same strand to separate the two directions. Audio is sampled from 48 kHz with frequency response from 10 Hz to 20 kHz within 3 dB. SNR is better than 80 dB, dynamic bandwidth reaches 101 dB and total harmonic distortion sits at -90 dB, which is enough headroom for program audio rather than only intercom or paging.

Connectors, Levels and Optical Budget

Transmitter inputs are female XLR and receiver outputs male XLR, both at 600 ohm impedance, accepting up to 4.0 Vp-p with 10 pF line input capacitance. Channel counts run from 2 to 32 inputs on the transmitter and the same number of outputs on the receiver. Optical output is -8 dBm within 2 dB, receiver sensitivity -25 dBm, and the ST/PC interface works over 50/125 or 62.5/125 multimode and 9/125 single-mode fiber.

Power, Climate and Distance Choice

Units are powered from 5 V DC at 2 A through a 90 to 240 V AC adapter and draw under 5 W. Operating temperature spans -20 to +75 degrees C, storage covers -40 to +85 degrees C, and humidity up to 95 percent non-condensing is tolerated, with MTBF quoted above 100,000 hours. Distance is model specific: 20 km on single-mode fiber or up to 2 km on multimode, with 40, 80 and 120 km builds available.

Picking a Kit Configuration

Uni-directional kits include F-2A-XLR-TxRX, F-4A-XLR-TxRx, F-8A-XLR-TxRx, F-16A-XLR-TxRx and F-32A-XLR-TxRx. Bi-directional options are F-2A-XLR-B-TxRx, the rack-mount F-2A-XLR-B-TxRx-RM, F-4A-XLR-B-TxRx and F-8A-XLR-B-TxRx-RM. Stage to front-of-house links, outside broadcast audio, intercom returns and inter-building studio feeds are the usual applications; pick a bi-directional code whenever a return path is required, and a rack-mount code when the units live in a studio or venue rack.