Join audio files into one

Arranging the sounds on the track

Every sound sits at its own place in time. Moving one does not push the others along, which keeps the rest of your arrangement exactly where you left it. A few habits make that easy to work with:

• Swapping two sounds: drag one down to Track 2 for a moment, slide the other into its place, then bring the first back up behind it.
• A file you forgot: Add sounds puts it in the list on the left. Press + on it to place it at the end of Track 1, or drag it to the spot where it belongs.
• A pause between tracks: leave a gap. Empty space on the track becomes silence in the file.
• Taking one out: click it and press Delete, then slide the later sounds left to close the hole.

The finished file runs from the start of the track to the end of the last sound, so check that nothing has drifted off to the right before you export.

Making the joins sound natural

Files recorded at different times rarely match. A song from one album can be much louder than the next, and a voice memo from a phone is often quieter than one from a headset. Two controls on the right fix most of it: Even out loudness brings each sound to the same level, and Volume lets you nudge any one of them up or down.

Sudden starts and stops are the other giveaway. A short fade at each edge, half a second or less for speech and a second or two for music, makes the change from one file to the next feel intended. Octoolo has no automatic crossfade, but overlapping two sounds on separate tracks and fading them past each other gives the same effect: fading audio in and out walks through it.

Any mix of formats in, one file out

The files you join do not have to match. MP3s, WAVs, M4A voice memos, FLAC tracks, WMA files from an old library and the sound of videos can all share a track, because Octoolo turns everything into 48 kHz stereo before it mixes. A mono recording simply plays on both sides.

Pick the output by where it is going:

• MP3 at 192 kbps for sharing, players and cars.
• M4A (AAC, 192 kbps) for iPhones and Apple apps.
• WAV or FLAC when the joined file will be edited further, since neither adds another round of compression.
• Opus at 128 kbps, saved as .ogg, for the smallest file.

One export can hold up to 300 sounds. If a folder of files only needs a new format, not joining, Convert sound files handles it in one go.

What people join most often

• Audiobook and lecture chapters that came as dozens of short files, turned into one file a phone plays from start to end without stopping between tracks.
• A recording that was cut short: a call or a meeting that stopped and restarted, so it ended up in two or three files.
• A podcast episode made of an intro, the conversation and an outro, with music on Track 2 under the opening words.
• A party or workout mix of songs from different albums, evened out and faded into one another.
• Voice messages from a family chat, kept together as one keepsake file.

Before joining, it often pays to tidy each piece first: trim the silence at the ends, and the joins take care of themselves.