In this tutorial, I’ll explain how to easily setup a music video playback rig that is also timecode ready.
Timecode can be represented as LTC, longitudinal time code, which is an audio signal. So if your audio hardware or editing program doesn’t support MIDI devices (Adobe Audition) or timecode output, then you can follow my alternative plan below.
I’m using Adobe Audition CC as an example for this tutorial, but you should be able to tailor this to any program that has a SMPTE time display option.
You’ll need:
- Laptop with available USB 2/3 port
- Audio editing program with SMPTE display (Audition, Pro Tools, etc)
- El-tee-see
- USB audio adaptor (cheap, 48k/24-bit support)
- Compact field mixer, 2-3 channels
- Denecke Timecode slate
- Comtek/IFB transmitter, multiple receivers
- mini TRS Stereo Male > (2x) TRS Mono Female splitter cable
- TRS Mono Male > XLR Male cable (to Mixer)
- TRS Mono Male > mini TRS Mono Male (to Comtek Tx)
- TRS Mono Male > mini TRS Mono Male (to Slate)
- 50 ft.+ XLR & power extension cables
- Powered PA Speaker (600W+)
The reason why I recommend to use a third-party, external USB audio adaptor is to isolate what you’re doing in Audition from the rest of the computer. You don’t want audio from other applications accidentally finding its way to the loudspeaker. Additionally, this will prevent accidentally blowing up your laptop’s built-in audio output or port. Just buy one that has 24-bit support and decent reviews.
Read the step-by-step completely and carefully below!
OS Setup
1. Install a USB Audio adaptor into your laptop. Generic USB audio drivers are already preinstalled with current operating systems.
2. In your OS Audio options, enable the built-in audio as the default audio output, i.e. the built-in audio port of your laptop. This will separate Audition’s audio from your OS and other applications.
3. In your OS Audio options, set the USB adaptor’s output to 48 kHz sample rate, 24-bit depth. If you need to choose other formats, keep it consistent across all steps in this tutorial.
Note: In Mac OSX, the keyboard volume controls typically adjust all devices at the same time, unless manually set in Audio options. Keep the “volume bar” at about 75-80%.
Audition Setup
4. In Audition, under Preferences > Audio Hardware, set Default Output to the USB Audio interface, name will vary. Test this by playing an audio file in Audition. You should only hear it off the USB adapter, and not the laptop speakers.
5. Create a new multitrack session, 48 kHz sample rate, 24-bit depth. If prompted, conform any file in this session to this format.
6. Create two mono tracks, hard pan one to 100% L, and the other to 100% R output. L track will be for LTC timecode audio signal, R track is for music. For even better results, mixdown the music track into mono first.
7. Right click on Time Display, and set it to your project’s SMPTE frame rate, i.e. 29.97 fps.
8. Go to El-tee-see, an online SMPTE generator that outputs an LTC wav file. Select your frame rate, select 48 kHz / 24-bit. Set a start time of 00:59:30:00 . This gives you 30 seconds before the 1-hour mark, which is the starting point of your music track. Download the resulting file. If this all works out for you, help out the developer with a donation.
Warning: LTC is an unpleasant noise, and is very freakin’ loud. Watch your ears when testing anything.
9. Insert the LTC file into the “L track”. Because it’s already stamped with timecode, the file should automatically place itself into the proper frame on the timeline. If not, use the time display to navigate to 00:59:30:00, and place the file at this frame.
10. Navigate to the 1-hour (1:00:00:00) point, and set a Marker (M key). Place the beginning of your music file on the “R Track” at this marker.
11. To test playback, insert a pair of earbuds into the USB audio adaptor, and only listen to the Right channel. The Left channel should just be noise (LTC). If you can barely hear some LTC bleeding over into the Right channel, that’s normal for a cheap adaptor, and shouldn’t affect the music.
12. So far so good – have a beer.
Mixer & Speaker Setup
13. Connect the mini-TRS Stereo Male > 2x Mono Female splitter cable, to the USB adaptor. Use 3.5mm adaptors if needed. This will hard split the LTC from the music. Label the connectors.
14. Connect the “Right” Female connector to an input on your Field Mixer, at line-level.
15. Try playing the session. The music is sent to the mixer, try calibrating the mixer’s peaks to +4 dB. If the incoming signal is too low — turn down the input all the way, set the input to Mic level, and slowly increase gain (more sensitive, watch your ears).
16. Pan the mixer’s Music input to Center, so that you can use both main outputs. Connect one of the outputs via XLR cable to your powered PA speaker.
17. Play the session, while keeping the mixer at calibrated level, and set your “loud” volume level on the speaker. This is your speaker volume when filming a take. From there, you control the music volume from the field mixer only.
18. Run line-level audio signal to cameras via an XLR cable(s), connected to another output on the field mixer. Adjust/calibrate accordingly.
Comtek/IFB Setup
19. Connect the “Left” Female connector to your Comtek transmitter.
20. Try playing the session. You should see solid levels reaching the Comtek transmitter, and the indicator light should be peaking. If not, increase the gain of the LTC track in Audition until the Comtek’s light peaks. In Audition, the Left output meter will be full-tilt, clipping past 0 dB. This is normal and the main reason why I’m using a USB adaptor.
Slate Setup
21. Configure the slate (i.e. TS-3, TS-C) to Auto frame rate, position #5, or the exact FPS of your project. Set to read-only mode via dip switch, so the slate won’t generate on its own.
22. Connect an IFB receiver to your timecode slate, with a mini-TRS Mono Male > TRS Mono Male. If your slate has a different input connector, wire appropriately.
23. Turn on the Slate, and turn on the IFB with the volume at its lowest point.
24. Play the session, and slowly increase the IFB’s volume. The numbers on the Slate’s display will twitch or incorrectly appear if the incoming signal is weak. Keep increasing the IFB receiver’s volume until the numbers appear stable.
25. Read all the notes / FAQ below. Have beer #2.
The 4-Count
Because new takes may start at different parts of the song, adding a sequence of beeps can help the performer get into tempo before jumping into a verse, chorus, or dance routine.
Create a new mono track, manually match up these generated beeps with the song waveform, and slide it around when necessary.
Some people like it, some don’t. Some take it personally, as if you’re doubting the performer’s ability to keep time.
Anyway, it’s still a helpful tool to prepare in advance, and it also keeps you (the playback operator) in time too.
Example Take
For the best results, here’s the flow for each take on a music video using song runtime on slate:
1. “Picture’s up – Roll camera” … Show slate, do not open sticks. Keep slate in frame.
2. “Camera speeds/rolling” … Start playback on timeline, about 10 seconds before the verse/chorus or any position in the song. Experiment.
3. “Roll playback” … Open sticks on slate, revealing the runtime. Pull slate away after 2 seconds.
4. 4-count beep, song rolls.
5. Cut.
It’s very important to start playback before the slate opens. Otherwise, the first slate timecode information the editor sees in the clip may be disfigured or incorrect.
Never scrub or transport to a new section of the song during a take, after the slate has been shown. If you run out of lead-in time before the song cue starts, ask for “2nd sticks” and notate it. Worst case scenario, if cameras are rolling at a standard frame rate, they’ll still receive the audio reference signals.
Huh?
What is timecode? SMPTE?
Timecode is a signal embedded into every frame of video, uniquely identifying its position with a time stamp in hours, minutes, seconds, and frames.
SMPTE (Society of Motion Picture and Television Engineers) set timecode standards to these frame rates: 23.976, 24, 25, 29.97 non-drop, 29.97 drop, 30.
What about other interlaced formats?
When filming at 60 or 59.94 interlaced, the base frame rate is still 30 or 29.97 FPS, respectively. If the camera doesn’t seem to accept the incoming timecode, double check settings with the camera dept.
Do I send song timecode to camera?
Simply put, if you’re stamping every file ingested into the camera with the same runtime timecode, later the video editing suite will juggle lots of clips that have identical addresses. This will most likely cause the software to eat itself, and unhappy emails.
Timecode for playback should only be displayed visually on the slate, which helps the editor place the clip properly on a frame-accurate timeline.
If there are multiple cameras filming at the same standard frame rate, they should all be jam-synced together, but on a 24-hour clock, while using the slate’s running time as visual reference only.
Can all devices have the same timecode?
Technically — You could jam sync the slate, cameras, and audio all together on a 24-hour clock. But this is as long as you’re filming at standard frame rates, and your field mixer has a timecode-enabled recorder (i.e. Sound Devices 633) connected to it. The editors will need your audio files.
This setup is assuming that you’re filming the music video linearly, from beginning to end, which is unlikely. The only references to song position is either the timecode-embedded audio files, or the on-camera audio signal.
An alternative would be to use two timecode slates at the beginning of the take — one for 24-hour sync, and other other for song runtime. It’s weird, and it adds more work for the camera department.
In all setups, you should also send audio signals to every camera, so editorial has another reference point if timecode doesn’t work out.
What about high-frame rate (slow-mo) filming?
When shooting in slow motion, cameras will disable all external timecode and audio during takes. It’s extremely important to still show the slate’s song runtime, regardless of frame rate.
What about “double-time playback”?
The director wants to do that cool effect where the background is in slow motion, but the subject seems to be singing in real time. This means the cameras and song are running at double speed and FPS.
Select the track in Audition, and use the Stretch function to shrink the song to 50%. Pre-render a double speed version in advance, and place it in a new Mono track. Timecode will still be the same as the original song, with no audio reference, so these takes will require manual placement.
If production absolutely needs timecode to run at “double-time” on slate, make a duplicate copy of the LTC timecode, and use the stretch function to decrease its size to 50%, for example. Make sure the stretch function is set to “pitch-accurate”, otherwise, you’ll have erroneous timecode displaying on your slate.
Why isn’t my slate showing stable timecode wirelessly?
If you’ve done everything correctly step-by-step, then keep in mind that you’re running audio through a wireless system, which could lose signals or encounter interference. Try changing to a clearer IFB frequency, check all cabling.
If you’re using a Comtek or IFB system with a lower TX output, like Comtek’s M216 Opt-7, which only has a 10 mW output, try using a 100 mW BST base station instead. More power = stronger signal. Raise the antenna above the crew and other equipment for better line of sight. This will become more problematic as more gear becomes wireless on set – monitors, follow focus, DIT, mics, jibs, etc.
If all else fails, hard-line a long length of BNC cable from the “Left Female” connector to the slate, with proper adapters if needed.
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Thanks for reading!