Each file is decoded.
Your browser's own decoder opens each file on this device. A mono file beside a stereo one is heard in both channels, and a file with more than two channels is folded to stereo.
SOLIPSIUM Super resolution audio engine
Free audio tool
Join voicemails, memos or takes into one file.
Choose two or more recordings and put them in order. Between them goes nothing, a gap of silence or a crossfade. Save the result as one MP3 or WAV.
Drop recordings here
Choose several at once. Your browser joins them on this device, and they stay there until you ask for a repair.
MP3, M4A, WAV, FLAC, OGG, Opus, WebM or AAC, mixed as you like, up to 30 minutes in all and 200 MB a file.
Your files, in order
Add another file to join it to this one.
Between the files
A gap adds up to 5 seconds of silence. A crossfade overlaps one file's end with the next one's start for up to 2 seconds, and never for more than half of either file.
Save the joined file
Check the joined file for noise
The quick check listens to the joined file in your browser for background noise, hum, clipping, dropouts and muffled sound. Solipsium's free try is built for speech, and after the check you can hear the first 20 seconds repaired with no account.
The check and the try take a joined file of five minutes or less.
Your first 20 seconds
After signing up, save the joined file and drop it into the editor to repair all of it.
What Solipsium hears
Make a free account to repair the whole recording
Then save the joined file and drop it into the editor. Scans and short repairs are free.
How it works
Every file is decoded to one rate first.
Files of different formats and sample rates can sit in one list, because your browser decodes each one at 44.1 kHz before the join. Each file keeps its own level, so a quiet one stays quiet.
The files are joined in order.
With nothing between them, each file's first sample follows the last one's. A gap puts silence between them. In a crossfade one file falls as the next rises, at equal power, so the level holds through the join.
The result is saved.
The MP3 has a constant bitrate, 192 kbps unless you choose 128, 256 or 320. MP3 files are made with lamejs, a JavaScript port of LAME, under the GNU LGPL. The WAV holds 16-bit samples and is not compressed.
Questions
Before you join.
Can I join files of different formats?
Yes, since each is decoded at 44.1 kHz first. A file this browser cannot open is left out, and the page says why.
One file is louder than the others?
Bring each file to the same loudness target with the normalizer first, then join them.
Should I use a gap or a crossfade?
A gap keeps separate messages, such as voicemails, apart. A crossfade blends takes of music or of one scene. To hear a join before you save, press Hear the join beside the later file: it plays from 3 seconds before that file starts.
Can I change the order?
Use Up and Down beside each file. The first file in the list names the saved file: Voicemail 1.m4a first makes Voicemail 1 joined.mp3.
Is anything uploaded?
Not to join the files. Your browser opens, joins and saves them on this device, and Solipsium's check runs in your browser too. Audio is sent only if you press Repair the first 20 seconds: then the joined file's first 20 seconds leave this browser, and Solipsium repairs them on its server and deletes them within an hour.
Hard to hear a voicemail?
The family recordings page checks a voicemail or a voice memo in your browser and offers the same free try.
Check a recording
The check and the 20-second try need no account.