Double Ender - Sync podcast files

For podcast editors

Get multi-ender recordings to line up.

Podcasts are frequently recorded over VOIP apps, with each participant using a local recording to ensure the highest quality. But nobody presses record at the same time, meaning you've got to spend time lining everyone up to a reference file (one containing all the voices together) before you can get to editing. What's worse, different audio devices can record at slightly different speeds, causing audio to drift out of sync over time. Double Ender is a free utility that syncs local audio recordings to a reference file so they all start at the same moment and stay in sync, without drift.

How it works.

Double Ender converts all files to Mono WAVs for editing. If files are recorded at slightly different rates, causing drift, it patches or removes areas of silence to offset the drift. If someone had to stop recording and then record a second file, it detects this, matches them, and syncs them together into one file. Exported files are labeled and named; your originals are untouched.

Version history.

1.7

Auto detect multiple sequential recordings from same person and merge into single, synced output file.
Cancel button is a proper button.

1.6

Rebuild of syncing method to scan the entire file, so sync over very long durations (30 minutes late or more) should be caught. (Thank you Shelly!)
Drift detection method rebuilt
Fixed some code conflicts
Unified the drop-zone pickers
Added Clear All menu item
If reference file isn't a mono WAV, leaves behind a mono WAV.

1.5

New, even more clever icon.
Added File menu and keyboard shortcuts for choosing files.

1.4

Support for 48kHz reference files (thanks, Michael)
Bug fixes including cold-launch URL drops, wrong-channel analysis, incomplete Cancel button, name and name collisions (thanks, Fable)

1.3

Better buttons and symbols
Auto-resizing main window
Default button grayed out properly
Foreground progress bar on Finder actions
About Box is more centered

1.2

UI polish (buttons!) and bug fixes
Better handling of stereo files with sound in weird places
Support for Finder labels
Less intrusive background operation when running from Finder service
macOS Sequoia support

1.1

Preferences window — control auto-populate, file renaming, completion sound, and loudness normalization
About window
Sync Files menu command (⌘S)
Loudness normalization: optionally normalize synced files to -16, -19, or -23 LUFS
Auto-update support via Sparkle