TC Bridge

TC Bridge is a protocol conversion mode. It takes an incoming LTC signal and fans it out to MTC, Art-Net, and OSC simultaneously — turning a single audio LTC feed into every sync protocol your rig needs, without LTCast needing to play a local audio file. It is the simplest way to add multi-protocol distribution to an existing LTC-based show system.

Enabling TC Bridge

Open Settings → Timecode In → TC Bridge tab and toggle Enable TC Bridge Mode on. Bridge runs independently of and in parallel with Chase mode — you can have both enabled at the same time, and both will respond to the same incoming LTC signal.

Configuring output routing

Choose which output protocols receive the bridged timecode. Each protocol has its own toggle in the TC Bridge settings:

• Forward to MTC output — the incoming LTC position is re-encoded as MTC quarter-frame messages and sent on the configured MTC MIDI port. The receiving MIDI device locks to the converted timecode.
• Forward to Art-Net output — the position is wrapped in Art-Net OpTimeCode UDP packets and sent to all configured Art-Net target IPs.
• Forward to OSC /timecode — the position is sent as an OSC message using the selected OSC format template to the configured OSC target IP and port.

Each toggle is shown as disabled (greyed out) if the corresponding output is not yet configured — for example, the MTC toggle is disabled if no MIDI port is selected. Configure the output first in Settings → Devices or Settings → Outputs, then return to the TC Bridge tab to enable that output's forwarding.

Bridge and local playback interaction

When a local song is playing back in LTCast, the TC Bridge output is suppressed to avoid sending conflicting timecodes from both the local file and the incoming LTC simultaneously. The bridge resumes automatically when local playback stops. This means TC Bridge is a background service — it is active whenever LTCast is idle and steps aside when you use LTCast's own transport.

Signal loss behavior

TC Bridge does not freewheel. When the incoming LTC signal drops, the bridged outputs simply stop sending updates. There is no last-value hold or internal clock takeover. If you need the outputs to continue during dropouts, enable Freewheel mode alongside TC Bridge — freewheel applies to the chase engine that TC Bridge reads from.

Common use case

You have a main LTC source — a MIDI playback system, a hardware timecode generator, or another machine — and you want to distribute it to your whole rig as MTC, Art-Net, and OSC without running separate physical cables to each console. Route the LTC audio into LTCast, enable TC Bridge, point each output at its target, and LTCast handles the conversion and distribution automatically. The main source does not need to know anything about the downstream protocols.