LTC MagicDocs

Recording Session to Edit

Film the session, give the recording engineer a clear timecode brief, and get audio back that you can reliably sync to picture.

Agree the handoff before recording. If the audio will be cleaned, edited or mixed before the video edit, retain a separate, unprocessed LTC recording alongside the music. Chasing timecode is useful when the engineer supports it; recording LTC gives you a recovery reference when later renders lose the metadata.

  • Verified timecoded BWFs: preserve original recording timestamps and place the delivered files at their source timecode.
  • Mixes or stems plus matching LTC: decode the LTC and stamp the aligned WAVs in LTC Magic.
  • PolyWAV containing music and LTC: identify the channel layout and split to mono when needed before stamping.
  • One stereo album mix plus one mono LTC file: preserve identical edits in both exports, then review LTC discontinuities with LTC Cut Splitter.

Skip to the engineer handoff brief if you already know the setup.

1. Set up the recording and cameras

Bring a charged Tentacle SYNC E, Deity TC-1 or compatible generator, plus the correct cable for the agreed input. An XLR audio input records LTC as sound; it does not become a dedicated timecode input just because the signal is timecode.

  • Agree the master timecode source, frame rate, drop-frame/non-drop-frame setting and session date. Distinguish 23.976 from 24, and 29.97 from 30.
  • For a dedicated timecode input, use the specified TC cable and output level. Confirm the recorder actually writes the expected file timestamp.
  • For LTC over an audio input, match the generator output to the mic/line input, set a clean unclipped level and label the isolated track LTC. Disable processing and automatic gain on that channel.
  • Leave phantom power off unless the exact generator and cable documentation explicitly requires it. Use the manufacturer’s specified adapter rather than an arbitrary mini-jack-to-XLR lead.
  • Keep LTC out of the music mix, PA and performers’ monitor feeds. Keep the LTC generator connected while recording the reference track.
  • Synchronise camera timecode boxes to the same master. Feed each camera’s TC input, or record audio LTC where supported. Retain camera scratch audio and a visible/audible slate as a fallback.

Check the camera’s frame-rate and slow-motion behavior. Timecode identifies positions; it does not by itself guarantee that independent audio and camera clocks run at exactly the same speed. Check the beginning and end of long takes for drift.

2. Chase timecode, record LTC, or both?

Chasing means the recorder or DAW follows incoming timecode position. Jam sync sets a device’s own generator to a reference. Recording LTC stores the timecode signal on an audio channel so it can be decoded later. These are different jobs.

If the engineer can chase and deliver verified original-time BWFs, that is a valid route. Ask what the exported timestamp represents: the original recording time, or the current position in the engineer’s edited session. A bounced mix is not guaranteed to retain the source recording time.

If chasing is unavailable or unwelcome, record LTC on a spare audio track. The engineer can work normally, provided the LTC reference and delivered music keep the same timing. Where practical, chase and record LTC for redundancy.

A single file-start timestamp cannot describe an album assembled from takes recorded at different times. Preserve the original source LTC through those edits, or request separate takes and an edit map.

3. Protect the reference through denoise renders

If your CEDAR denoise renders have been arriving without their original timecode metadata, treat the rendered files as untimestamped until checked. Agree this with the engineer before cleanup and keep untouched recording masters plus the isolated LTC track.

Metadata loss depends on the application, version, integration and export settings. Do not assume every CEDAR workflow removes metadata, or that every noise-reduction tool preserves it. RX provides BWF and metadata-preservation options; Pro Tools timestamp behavior also depends on the render mode.

Process the music, not the LTC. Keep the reference free of denoise, EQ, limiting, fades and time stretching. If cleanup changes the music’s length, start position or latency, restore alignment before pairing it with the LTC. Preserved metadata alone does not prove the audio still lines up.

Before the session, run a short recording through the actual CEDAR or other cleanup chain, export it exactly as planned, and import it into the destination editor. Check the timestamp and the sound against picture. Repeat after workflow changes.

4. Send this brief to the recording engineer

Copy the following and fill in your agreed frame rate and recording format:

Please supply uncompressed WAV/BWF files at our agreed sample rate and bit depth, and document the frame rate and DF/NDF setting. Keep the original recordings. For a straightforward stamping delivery, integer PCM WAV at 24-bit/48 kHz is a practical option; confirm compatibility with our LTC Magic version before exporting.

If supplying timecoded BWFs, preserve the original recording start timestamps through cleanup and export. Please state whether the timestamps refer to recording time or your current session timeline. Send a test export from the full processing chain, including CEDAR if used.

If supplying LTC separately, send an unprocessed mono LTC WAV and the matching stereo mix or stems. Export all from exactly the same timeline selection, with the same sample rate, start, end and sample count. Keep leading silence. Apply every cut, rearrangement and removed gap identically to music and LTC; do not independently trim or process the LTC.

For a whole-album delivery, send Album_Mix.wav and Album_LTC.wav with identical timing and edits. Preserve the original recorded LTC through the edit rather than generating new continuous album timecode. Retain the per-take sources too.

For a polyWAV, include a channel list identifying LTC. With every delivery, include the session date, take/song list, export settings, frame rate, known offsets, timing changes and any metadata problems. Please disclose processing latency, speed changes and crossfades between different takes.

5. Receive files with valid timecode metadata

Check the delivered BWF timestamp and frame-rate interpretation in your editor. Place files at their original/source timestamp, then verify against camera timecode and a slate. A filename or a timecode display in the engineer’s session is not proof that the delivered WAV contains the right metadata.

Repeat the check after processing. If metadata has gone missing, use matching untouched originals or aligned recorded LTC to recover the timing. If the delivery is an edited session, request the supported AAF or timeline interchange and referenced audio, not just a mix bounce. See Timeline Builder for supported handoffs.

6. Receive LTC recorded as audio

  1. Keep originals and write all outputs to a separate folder. Confirm the sample rate, format, frame rate and channel map.
  2. If LTC is inside a polyWAV and you need discrete channels, use PolyWAV Splitter. Identify the LTC output and keep matching music channels together. Splitting does not decode or stamp timecode.
  3. Choose the LTC source/channel and only pair it with audio that shares its sample origin. Matching names or duration alone do not prove alignment.
  4. Use Single for one aligned set, or Grouped Batch for multiple consistently named sets. Confirm the expected frame rate and review the decoded start time before processing.
  5. Write stamped outputs, review the report and import them into the destination editor. Verify picture sync at the start, middle and end.

Check Supported File Types for your release. Do not assume that splitting a 32-bit float polyWAV converts it to integer PCM. If conversion is needed for stamping, preserve sample rate, start position and sample count across the entire set.

Detailed steps: PolyWAV Splitter, LTC Timestamping and Grouped Batch.

7. Receive one stereo album file and one LTC file

This is a useful handoff when the engineer prefers a single album export. The stereo music and mono LTC must be two exports of the same edit, with identical starts, cuts, gaps and lengths. For example, if music moves from take 3 to take 7, its LTC must make the same move at the same sample position.

Add both WAVs to LTC Cut Splitter, select the LTC source and frame rate, choose Preview Segments, and compare the detected boundaries with the take list before splitting.

Cut detection finds discontinuities in the recorded timecode, not songs or musical edits. Continuous LTC across several songs may have no cuts to detect. Newly generated album-timeline LTC cannot recover the original camera times. Small jumps, damaged LTC and very short sections require particular care.

Check both the album positions and original camera-time positions in the receiving editor. Segment placement and source timecode can be represented differently in BWF and iXML metadata; do not assume every editor will interpret the output identically. Verify a test segment before relying on automatic camera placement.

A crossfade between two takes contains two source times at once. One LTC track cannot fully describe that overlap. Ask for separate source takes and an edit map or supported timeline interchange when the edit cannot be represented by one clean LTC sequence.

8. Check the handoff before editing

  • Correct session/day, take names, channels, sample rate, frame rate and DF/NDF setting.
  • Music and LTC share the same sample origin and edit; no independent trims or unaccounted processing delay.
  • Delivered timestamps have been checked after cleanup, not only before it.
  • Picture sync holds at the start, middle and end; any drift is investigated separately from a constant offset.
  • Cut boundaries and segment placement are reviewed; music crossfades and missing LTC are documented.
  • No LTC is audible in music deliverables; originals, LTC references, edit notes and processing reports are retained.

A constant offset suggests a placement or latency problem; a growing offset suggests clock or speed differences. Neither is fixed simply by repeating a timestamp operation. Use the validation checklist and troubleshooting guide when checking results.

Technical references

The CEDAR example above describes a delivery problem to test for, not a claim about all CEDAR products or settings. Device connections and software options should be checked against the versions in use.