Audio · exFAT recorder card
PCM WAV: recover after an interrupted recording
What can I do with PCM WAV recordings after a recording interruption?
Short answer
Often the audio is still there: when power fails mid-take, the recorder may not have written the final data length into the WAV header, so the file shows zero or a short duration. Copy the file first, then correct the RIFF and data chunk sizes in the 44-byte canonical header of the copy.
The situation
PCM WAV recordings is missing, too short or unreadable after power loss, a card error or an unsafe stop.
The samples are usually on the card in full and only the two length fields in the header were never updated. A player therefore reports zero or a few seconds and stops, although the file on the card is as long as the take really was.
01 / Diagnose
Work out what actually disappeared
A recorder writes the WAV header first with placeholder sizes and corrects them when it closes the file. If power fails or the card is pulled, the RIFF size and the data chunk size keep those placeholders. In a canonical 44-byte PCM header, these two fields are all that stands between you and a playable take.
The payload may have been written before duration fields, indexes, directory entries or closing structures were committed. For PCM WAV, this matters because RIFF, fmt and data chunks describe channels, sample rate and payload length
Check the last known path, trash and backups without writing to the original device.
02 / Protect the source
Preserve the best recovery chance
- 1
Switch the recorder off, remove the card and copy the affected file before any tool touches its header.
- 2
Note sample rate, bit depth and channel count, because the corrected sizes must match the real sample count.
- 3
Work on the copy and set the RIFF size and the data chunk size to the actual length of the file.
- 4
Play the corrected copy end to end and keep the untouched original beside it in the same folder.
Do not let the recorder repair the take on the card itself, and do not edit the header of your only copy. If the calculation goes wrong the file becomes unreadable, a second attempt has nothing intact to start from, and further recording covers the samples.
03 / Choose the method
Match the tool to the source
For stable, readable exFAT, NTFS and FAT16/FAT32 or uncompressed IMG, DD, RAW and BIN images.
Unconfirmed exports are marked .UNVERIFIED.
File Recovery Hero reads the recorder card read-only and recovers takes that are no longer in the directory; it does not edit WAV headers or repair individual damaged files, so the header correction belongs to an audio tool on a copy. Encrypted or physically failing cards stay out of reach.
04 / Verify
Check the recovered content, not just its name
The correction worked when the player reports the full duration, the audio runs to the last second and the voices or instruments sound as they did in the room. Rising hiss, half-speed playback or metallic distortion means sample rate, bit depth or channel count in the header do not match the recording.
Keep the source until two verified copies exist. One working preview is not enough.
Sources and technical references
FAQ
Questions about this recovery case
Can exFAT recorder card be recovered in this situation?+
The samples are usually on the card in full and only the two length fields in the header were never updated. A player therefore reports zero or a few seconds and stops, although the file on the card is as long as the take really was. The result still depends on what remains readable on the source.
What should I avoid before scanning?+
Do not let the recorder repair the take on the card itself, and do not edit the header of your only copy.
Does scanning write to my memory card?+
Your memory card is only read. Nothing is saved to it.
How do I know whether the result is complete?+
The correction worked when the player reports the full duration, the audio runs to the last second and the voices or instruments sound as they did in the room.