Repairing corrupted WAV files from ZoomH4 SD card
Published by on July 14th, 2007
I discovered a little problem this weekend using the ZoomH4 field recorder: some audio files were not correctly writing to the SD card, delivering a “card error” alert at the end of the recording. This was worrying after recording several sound segments in locations I rarely visit.
The problem surfaces after the first two or three recordings on the card. Each subsequent recording on the same boot-up of the unit, generates this error. Switching off then restarting the H4 offers a properly formatted audio file as it should. As the H4 almost continuously writes data to the card during recordin, I found that all the audio data was there in each file, it just was not being recognised as a fully formed WAV file when connected and downloaded to my computer. As it turned out, recovery was straightforward.
I use AmadeusPro as an audio editor. It’s fast, reliable, and responsive, and also offers a “Import Raw Data” capability. I suspect other good audio editors offer that too. What is necessary for Raw import is foreknowledge of the original audio recording’s details such as sample rate, compression, etc. By examining one of the correct WAV files from the H4, I was able to determine these details and set AmadeusPro to import accordingly. Import was straightforward and the result was a complete audio file as recorded.
The corrupt file situation is not desirable, but at least recovery is straightforward and I can be confident that the error is not losing me any of the recorded data. This could be down to a less than top notch quality SD card - I must admit it was pretty cheap, despite apparently being a reputable brand - so I’m going to test with other cards to verify whether it’s the card or the recorder.
UPDATE: Updating the H4’s firmware to version 1.30 seems to have fixed the issue. Updating is a doddle. Thanks to James for mentioning the firmware update.
UPDATE 2.0 on July 23: The problem persists, but is intermittent. I did five 1 minute recordings yesterday at the British Musem, and only the fifth generated this issue. I can live with it for now until I get another SD card to figure out if that might be cause it.
3 Responses to “Repairing corrupted WAV files from ZoomH4 SD card”
Sounds troubling.. thanks for the ‘heads up’. I shall try it myself, too.
I think I’ve recorded a few WAV tracks in ’stereo’ mode in one session without problems… the first thing I tend to do (fool that I am?) is update the firmware on new kit that I get in. So, fairly good results on 1.30 on my H4 with a *very* cheap SD card. YMMV.
Thanks for the heads up. Need to check which SD card I have in my unit. Will report back if I experience a similar problem.
- Neil.
@james: Ah, yes, firmware… just done that, thanks for reminding me. I’ll test for the persistence of the problem and report back. Very impressed at the ease of upgrading the firmware, they really have that sorted.
@Neil Ford: You up to V1.30 firmware?