Did not Shut Down and Lost Recording

[WaihekeSoundieParticipant]

Hi there,
Hoping someone may be able to help. I recorded a show last night but the desk was powered off before I had chance to run the shut down sequence – in fact I suspect I may not have actually even stopped the recording before power was lost.

I see today that I now have 18ch of 512byte (0 length) files even though my harddrive is telling me that I have actually got 32gb used on there somewhere- I cant see those files even when I view hidden files. Also if I copy the short wav files off the hardrive one whcih I recorded them – sure enough they come off as 512byte files- I can open them but they are empty.

So it seems that the content of my files is still on the harddrive but not associated with the file headers or something.

I do appreciate that this is not a “fault” but it is very disappointing. Always stop the recording and shut down properly before powering down.. does anybody know how I might be able to recover my show?

[[XAP]BobParticipant]

You likely have unassociated data as you say. Should be able to recover it with pretty “normal” recovery software.

I’m cautious, so I’d take a full disk image first (using dd), then play with that instead of the disk.

I’d be googling for the software, since I haven’t had to do this in about two decades…

[WaihekeSoundieParticipant]

Thanks for that advice. Not had any luck so far but will keep trying.

Perhaps a reason I hadn’t considered why streaming over USB for recording is a little safer- a laptop DAW would handle the loss of connection to the desk much more gracefully than it seems a HD does mid write.. (Assuming the loss of power was the issue and that I don’t simply have an (unrelated) HD issue).

[[XAP]BobParticipant]

It’s a reasonably likely error for a direct HDD recorder to have. The wav header is written, but the remainder is sat in inodes which haven’t been tailed onto that file yet. You just need something which can figure out the inode pointers, and you should end up with 18 “almost” wav files, which need the header adding.

Hopefully.

I’d reckon all is not lost, but I’ll reiterate, I’d be working on a disk image, not the raw disk.

Possibly a case for a small UPS as well?

[WaihekeSoundieParticipant]

I’ve looked on the the disk with a disk recovery scanner and boy there is a lot of old stuff still on there hidden away but I can’t find 18 large files looking like they need a header. I think I may have to chalk this up to experience and move on.
Yep perhaps a UPS OR record via USB to a DAW and laptop: wee bit more hassle but safer I think. Or maybe direct to drive and over the USB simultaneously if it is a really important recording.

Thanks for you help though.
Andy

[MarkPAmanParticipant]

Adobe Audition allows you to “Import” “Raw Data” – (then sometimes you need to fiddle to set the correct sample rate & bit depth) and re-save. I have used this to fix similar problems in the past – though obviously if you can’t find the files that’s not going to help.

I assume this is possible on the free trial version.

[[XAP]BobParticipant]

They might not be large files yet – in which case it would be alot harder to piece them together.

Having information about the way the files get written could help, but you might be out of luck 🙁

[WaihekeSoundieParticipant]

Yeh.. I don’t think they are big files yet and I can’t find anything with a corresponding date/time.. There are about 1,700 files on there .. Ah well.

Lesson learned. Take heed folks: if recording direct to QDrive
— Stop your recording and shut down desk before you power down;
— Consider a ups else you will prob lose your recording if you lose power;
— consider streaming to Laptop & DAW if vital. Note you can do both concurrently.

Thanks for your help though guys.
Andy
Waiheke Island NZ

[DavecParticipant]

I did the same thing. I used windows disk tools (right click on the drive) and it recovered 18 large files. I managed to recover them as WAV files them in Audacity, importing them as RAW files and filling out the details. There’s a thread about it here with the settings you’ll need.

It’s raining here in Greenhithe.

[mamericaParticipant]

The bad news is it’s gone. The good news is you probably won’t do that again. I did the same thing last summer. I’ll never replace the recording but I won’t forget the lesson…

[HawkParticipant]

OMG, I just had the same experience. Someone plug it out while it’s recording. Is there a way to recover the file? Davec, what tool did you use to get the raw data back? The windows disk scan does not seem to work for me.

[DavecParticipant]

I just right-clicked the drive, properties, then tools and used the error-checking tool there. I think it’s the old chkdsk. Anyway, it created 18 files chk0001, chk0002 etc, or something similar. This is Win7.

[HawkParticipant]

mdir /tmp/usbstick
cp /media/usbstick/FOUND.000/FILE{54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71} /tmp/usbstick
cd /tmp/usbstick
for f in ls *.CHK; do 
  echo $f
  cat $f | tail -c +3 | sox -r 48k -e signed -b 24 -c 1 -L -t raw - <code>basename $f .CHK</code>.wav
done

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