“Lock the lights to the tracks” sounds simple. In practice it’s a chain of standards: linear timecode (LTC) on an audio cable, MIDI Timecode (MTC) on a USB or DIN cable, MIDI Clock as a tempo reference. Pick the wrong frame rate and your two-hour show drifts by 8 seconds. This guide walks through the formats, the routing, and the gotchas that bite worship and touring teams.

What each format is for

LTC (Linear Timecode)

Audio-rate timecode, distributed as an ugly square-wave signal on a regular audio cable. The most common timecode for locking lights, video playback, and other DAWs. Lives in the audio domain — runs at line level over an XLR or TRS just like any audio source.

MTC (MIDI Timecode)

Same timestamp data but on MIDI cables (5-pin DIN, USB MIDI, RTP-MIDI). What most DAWs and softsynths use to chase position. Lower resolution than LTC but easier to plug in.

MIDI Clock

Tempo-only. Tells receivers “the tempo is 120 BPM” and the beat position. Doesn’t carry absolute time. Used to sync arpeggiators and delays to song tempo, NOT to lock a light cue to second 47 of a song.

Frame rates (and the one that drifts)

24 fps — film. Mostly irrelevant for live audio rigs.
25 fps — EBU/PAL video. Default in Europe.
30 fps non-drop — older video. The default in many DAWs.
29.97 fps non-drop — NTSC video. Runs slow vs real-time by 0.1%. This is the one that drifts.
29.97 fps drop-frame (29.97DF) — NTSC with periodic frame-drops to stay matched to real-time.

For audio-only rigs, pick a frame rate that doesn’t require drop-frame math: 30 fps non-drop is simplest. The only reason to use 29.97 DF is if your video/broadcast chain demands it.

Generating timecode from your DAW

Ableton Live

Ableton doesn’t natively output LTC, but the “Timecode” device (Max for Live) or third-party plug-ins (e.g. the free LTCGenerator AU/VST) sit on a track and output LTC synced to the transport. Route the LTC track to a dedicated audio output that goes to your lighting console.

Playback (MultiTracks)

Native LTC output — assign LTC to a physical output in the Settings → Outputs panel. Plug-and-play.

Pro Tools

Pro Tools generates LTC via the SYNC HD/X hardware option or via the Avid MachineControl plug-in. For live use the SYNC hardware is the standard.

Standalone LTC generators

Brainstorm SR-112 / SR-15+, Sound Devices 633 internal gen, Tentacle Sync E — all generate LTC from their own clock with no DAW involvement. Useful when the DAW isn’t the master.

Receiving timecode in lights, video, and other DAWs

Lighting consoles

ETC EOS / Element / Ion — accept LTC on an audio input or a dedicated SMPTE port. Set the ”Show Control” preferences to chase LTC.
GrandMA / GrandMA3 — LTC over a dedicated input. Frame rate is set per show.
ChamSys MagicQ — LTC via USB audio interface or built-in input depending on model.

ProPresenter / Resolume / video servers

ProPresenter chases LTC via the Sync tab. Each cue / clip gets a SMPTE-locked trigger.
Resolume chases LTC or MTC and locks each composition’s playhead to it.
QLab can either generate or chase LTC. Often the broadcast world’s master.

Other DAWs (Pro Tools, Logic, Cubase)

Set the DAW to “Slave to LTC” / “Chase LTC” in synchronization preferences. The audio interface routes the incoming LTC signal to the DAW.

A redundant timecode chain

For broadcast-critical worship and theatre:

Generate LTC from BOTH playback laptops in a redundant rig (see Redundant playback rigs).
Sum both LTC signals to one bus through an audio switcher (or use a “diode-OR” box) so the active laptop’s LTC reaches the receivers.
Confirm both timecode streams are at the same frame rate and the same starting offset.

Common gotchas

LTC degraded by compression. Don’t route LTC through a console’s compressor or dynamics-on bus. It’s a square wave; processing it as audio destroys the timing edges.
LTC running through digital snake.Most digital snakes are fine, but a few introduce enough latency to put LTC out of sync with the audio. Test on the actual production gear, not on a substitute.
Mute groups. A scene change that mutes the LTC output bus kills the chase. Make sure your LTC output is unmute-safe.
Frame rate mismatch. Already covered, worth saying twice.
LTC over Bluetooth or Wi-Fi. Don’t. The jitter is too high.

Plan the rack

Add your playback interface’s LTC output to the rig in IEM Rig. The signal-flow visualises the LTC path from the interface’s output XLR to the lighting console’s input.

SMPTE Timecode for Worship and Touring: Locking Tracks, Lights, and Video