Drop a file.
MP3, FLAC, WAV, M4A, OGG or Opus, up to five minutes. Your browser decodes it at 48 kHz, the rate Solipsium's editor works at.
SOLIPSIUM Super resolution audio engine
Free audio spectrum check
See where your audio really stops.
Drop a song or a recording to see its spectrogram, the height where its sound stops and what that usually says about the file. It is free and works in your browser.
Drop an MP3, FLAC or WAV here
The spectrum is drawn and measured in your browser. It stays on your device until you ask for a repair.
MP3, FLAC, WAV, M4A, OGG and Opus, up to five minutes.
Where the sound stops
Time runs left to right and pitch rises upward; brighter is louder. Where the sound stops, the empty space above it is outlined.
| Average bitrate | |
|---|---|
| Channels | |
| Length |
The bitrate is the file's size divided by its length, so it includes cover art and container data.
What is this recording?
Speech gets the quick check from Solipsium's editor and, when it finds something the free try repairs, an offer to repair its first 20 seconds.
Solipsium's free try is built for speech. For music, a free account's editor can run AudioSR on a passage of up to 60 seconds, and what it adds is inferred.
Your first 20 seconds
After signing up, drop the same file into the editor to repair all of it.
What Solipsium hears
Make a free account to repair the whole recording
Then drop the same file into the editor. Scans and short repairs are free.
How it works
What the picture shows.
A spectrogram draws a recording over time, low pitches at the bottom and high ones at the top. Saving a file at a low bitrate usually throws away its highest sounds first, so where the sound stops says a lot about how the file was made.
See where the sound stops.
For every 5 seconds, the page finds the highest band still within 45 dB of the level between 0.5 and 4 kHz, the measure the editor's scan uses, and shows the middle value.
Read what it usually means.
A stop near 16 kHz is typical of a 128 kbps MP3; one above about 19.5 kHz fits a 256 or 320 kbps MP3, a WAV or a FLAC file. Some encoders cut on purpose, so treat the reading as a strong hint.
Questions
Reading a spectrum.
How can I tell if an MP3 is really 320 kbps?
Look where its sound stops. A 320 kbps MP3 usually reaches about 20 kHz. A 256 kbps one reaches nearly as high, so the picture cannot tell those two apart. One that stops near 16 kHz was probably made from a 128 kbps file and saved again at a higher bitrate, which cannot bring the top back. Some encoders cut lower on purpose, so read the picture as a strong hint, not proof.
Is a FLAC file with a 16 kHz cutoff fake?
Probably it was made from a lossy file such as an MP3. But some recordings are narrow by nature: old tapes, voices and soft instruments may have little sound that high. The picture shows where the sound stops, but a spectrogram cannot prove a file lossless.
Why is the bitrate only an estimate?
It is the file's size divided by its length, so it includes cover art and container data, and a file with a variable bitrate shows its average. Where a file's own headers name a bitrate, as an MP3's do, this page does not read them.
Why does the picture stop at 24 kHz?
The file is decoded at 48 kHz, which holds sound up to 24 kHz. A file saved at 44.1 kHz holds sound up to about 22 kHz, and one saved at 32 kHz stops at 16 kHz, whatever its bitrate.
Can the missing top of an MP3 be put back?
Not as it was: what the encoder removed is gone, and the free try does not rebuild a top that stops above 11 kHz. For music, a free account's editor can run AudioSR on up to 60 seconds of a song, and what it adds is inferred.
Is my file uploaded?
Choosing a file does not upload it: the picture and the numbers are made in your browser. For a speech recording, the page can offer to repair its first 20 seconds. Only pressing that button sends audio to Solipsium, and the note beside it says what goes.
A voice that is hard to hear?
Drop the recording on the family recordings page. Solipsium checks it in your browser and can repair its first 20 seconds for you to hear.
Check a voice recording
The check and the 20-second try need no account.