Sync Beep

Capturly mixes a short tone into the start of your audio. It exists for one reason: to give you an unmistakable alignment point when you line several tracks up in post.

What it is

Property	Value
Frequency	1000 Hz
Duration	0.5 seconds
Position	Mixed into the first half-second of the audio
Level	Mixed with your microphone input, not replacing it

It’s a pure tone, so it reads as a flat, solid block in a waveform view — nothing in speech looks like it.

Which recordings carry it

The beep is generated by the desktop and mobile recording pipelines. It is not present in browser recordings.

Where you recorded	`*_audio.wav`	`*_video.mp4`
macOS desktop	✓	✓
Windows desktop	✓	—
iOS / Android	✓	—
Browser	no WAV	—

On macOS a single FFmpeg process writes both files from one mixed audio graph, so the beep lands in both. On Windows the WAV comes from a separate audio process and the MP4 from the capture engine, so only the WAV carries it.

If you’re syncing a browser take, use a clap, a verbal countdown, or the waveform itself as the reference point instead.

Why it matters

The multi-track problem

When you record several participants, or sync audio to video:

Files start at slightly different times
Clocks on different computers drift
Manual alignment by ear is tedious and imprecise

What the beep gives you

A visual spike — easy to identify in any audio editor
The same marker in every participant’s file — recording starts together
Sample-level precision — zoom in and align the leading edge

Using it in post-production

Two tracks

Import both files into your editor
Zoom in on the first second of each track
Find the tone — a solid block, obviously not speech
Align the leading edges by sliding one track
Verify by playing back

Three or more tracks

Pick a reference track — typically the host
Align every other track to it using the tone
Lock or group the tracks so nothing shifts
Trim the first second from all tracks at once

What it looks like


____|████|________________  ← 0.5 s at 1000 Hz
    ↑
  leading edge — align here

Editor-specific notes

Adobe Audition / Premiere Pro

Import all tracks into a multitrack session, zoom to the head of each, and slide tracks so the leading edges of the tone line up. Premiere’s Merge Clips with audio as the sync point also works for pairing a WAV with its MP4.

DaVinci Resolve

Add everything to the Media Pool, drop each participant on its own track, enable waveform view, and align at the head of the timeline.

Audacity

Import each WAV as a separate track, then use the Time Shift tool to align the tones.

Reaper

Insert each file on its own track, zoom to the head, and drag to align. Turn snapping off for sample-level precision.

Descript

Descript often detects sync points on its own. Use the tone to confirm or correct what it picked.

Tips

Don’t talk over it — leave a beat after the beep before you start
Align visually, not by ear — zoom in rather than trusting playback
Check sync at the end too — on long takes, clock drift between machines can accumulate; re-sync at intervals if you see it
Trim it last — align and lock first, then delete the head from every track together

Troubleshooting

I can’t find the tone

Look at the very start of the file and zoom right in
Check you’re looking at a file that carries it — see the table above
Browser recordings have no beep

The beeps don’t line up

Verify every file is from the same session — the session ID in the filename should match
Check the files weren’t trimmed on import

Audio drifts over a long recording

Different machines’ clocks run at fractionally different rates. Re-sync at intervals, or time-stretch a track slightly to match. This is drift between devices, not a fault in the recording.