MX 24242 power cut during recording, lost data

christubef

New member
Hello,

sorry for my english, i'm french,

one night this week I was sounding a jazz concert with my LS9 digital mixer and at the same time I was recording the concert in "direct OUT" and multitrack with my multitrack Tascam MX 2424 connected in adat. to make a new mix of the concert later.

But there was a blackout during the concert just a little before the end while the MW 2424 was in recording mode. No inverter, so mx 2424 sees no trace of what had been recorded.

so I stop using the hard drive that is in the mx2424 waiting to go home, once at home, I put the hard drive mx2424 on my computer to see a little what there inside: and so, I see my Wav files corresponding to each track but these are illegible, nor copiable on another retrieval. it is even indicated 0 byte on these wav nor any information on the properties of these file wav (sampling frequency quaniacetion etc). I know that every time I stop a recording on the mx2424, it must write information on the index of the disk partition, update its info files of the current project, and finalize the wav file, so if we suddenly cut the power, the machine does not have time to write this data and so at the next restart it does not know that there is new wav file. Yet I know that the data is written on the disc and my question and how to find them ??

to try, I took another hard drive that I put in the mx2424, I run a record and turn off the power to generate the same file failure on another disc story to tinker first on a disc of test in case I make a false manipulation that would actually lose me the data (you never know)

I tried "easy recovery pro": he found nothing, I launched a CMD chkdsk command that did not find anything, I also did an analysis with "recuva" which finds the files but also at 0 bytes therefore unusable ...

I do not know what to do, i need a softwar it "search" the entire disk without requiere to the indexes of the disk, or create a file that allows the data corresponding to these wav files to be located.

I want to have the help of computer scientists.

Thank for your help,

CHris
 
Hi there,
Sorry to hear you lost (perhaps temporarily?) your data.

Sounds like you have the right idea, being careful. I think I'd take a drive clone with something like CCC, if you happen to have a spare,
or, at least, take a zip of the important files whether broken or not.

Sounds like data recovery isn't going to be useful here because it's going to recover the data (duh) which is corrupted, rather than 'missing'.
There are various tools out there which claim to be able to repair corrupted or damaged wav files.

Would you be happy to share one of the files for anyone who may have time to tinker or try a few things?
 
Hi,

On another hard disk (disk 2), I make a recording operation of the same duration with the same project name. I also make a total "gost" of the disk on which the data are missing (disk 1) to another disk (disk 3) in which I will do my experiments. On disk 3 I will replace the files (that the MX 2424 updates at each recording stop) with those of disk 2. These files indicate the mx2424 the structure of the project when loading and allows the location of Wav and editing in the tracks. But I do not think it will work. I think the MX 2424 will try to look for WAV, it will find but these wav files are only 0 bytes. The problem is that the Wav are unfinalized. I think that while recording the MX2424 writes the raw data in different clusters of the disk and at the moment of the stop recording it creates the WAV file and indicates in the disk partition table where the data of each disc is wav. In my problem, I need located this unreported audio data.
 
67646204_2184004561696795_8970123731242319872_n.png

here is a screenshot on the view of my disk. the wav files are there but it's only 0 bytes, and I can not read or copy it.
 
so following my attempt explained in my last message, the mx2424 signal that the WAV data is bad. Even with the session now updated.

tried the application: WAVFIX but I can not use it. I will ask more gifted friends for help with a computer.
 
If you used the disk with the original application after the power failure it may have closed the file "properly" even if wrong. If the file was written sequentially (un-fragmented) it might be possible to read the data.

I had luck using Audacity to import a zero-length WAV file using an "import raw" mode (sorry, don't recall details). You have to experiment with an offset byte, or something like that. If you have the original disk and it's not been corrupted by using anything that would do any writes, you might google for the solution with Audacity and see if that helps?
 
tried the application: WAVFIX but I can not use it. I will ask more gifted friends for help with a computer.

It needs to be run from the command prompt, with parameters to tell it what to do.
The easiest approach, if that's foreign to you, is probably Start>Run>"cmd" (OS dependant) then just drag the wavfix exe into the terminal, and then one of your broken wavs into terminal, then hit enter and read the output.

That should save you having to type out the file paths manually.
 
I am sorry to say that I think you may have no luck recovering the data. The MX2424 does not complete the writing of the file until you hit stop. There is information being written as it recorded but it finalises the file upon hitting stop. There are numerous warnings about turning the MX off during recording, hard drive formatting, etc. I also recommend to anyone that is using an MX that they have a UPS (uninterrupted power supply) on the mains to prevent problems like you encountered.

Alan.
 
So, with a friend, we tried "wavfix". it did not find anything on the 0 byte wav file. I did an analysis with Recuva, he found random "wav" files erased, I retrieved this data and read with a reader and I heard sound clips with many read errors, but I do not I heard no sound corresponding to the desired content. . I think that recuva uses the disk partition table to search. In fact, I need software that reads the disk without using the partition table. Or, I need an app that can edit the partition table to make this data localizable. I do not have a program that shows me the partition table of the drive, the ones I have tried show that the contents indicated present and erased. If I can access the partition table and copy and paste the settings, I would create a similar recording project on another disk and, at the end, I would copy the partition table information to the disk containing the corumpus data. .
 
I know I was negative in my belief that anything can be recovered, but I am following this thread with interest as I would love to be proved wrong.

Alan.
 
I also am skeptical that anything can be recovered, but would love to see it work out. I'm an old computer dude and have had many issues with data copies that were broken because of various reasons. The thing is, abnormally stopping a transfer, be it recording or copying a file, doesn't allow the file to be completed. Sure, you will have the file name and the zero bytes, but that's because the process began correctly. To have a contiguous file, you must have the whole file copied and the process of writing it completed, too.

Years ago, I had a boss who was very busy and always in a rush. He was a millionaire, damn smart and a very nice guy. This was in a mortgage corporation and he was doing hedge funding. He had a formula on a white board that was six feet tall and at least 12 feet wide, of nothing but calculations. Did I say he was smart?

Well, because he was always so busy, and always in a hurry and every file he worked on, with that formula was huge...when he saved something, it took a while for the save to complete. But, with many very smart people, they aren't always smart in all ways. He wasn't that smart in how computers work and one day, when he was in a very big hurry to catch a plane, he had just finished this file and then he hit "save".

He immediately closed his laptop and was off to the airport. When he got to his destination, there was no file. It hadn't saved. My boss and I tried to explain to him that because the file was so large, it took a while to save from beginning to end. He had hit the save button and didn't wait for it to save the whole file. Consequently, none of it actually got saved, because the save process didn't complete.

That's usually how computers save files. There is a beginning, where it creates the file, creates a temp file and the process begins. But, if that temp file isn't allowed to be converted to a finished file, it's the same as it never existed. Sometimes you can find bits and pieces with something similar to chkdsk, but sometimes a file isn't saved in one complete location. I would assume audio files are saved in one complete location, but still doesn't help much, if the save process never completed. I have recovered bits of text data, when power went out, and have been able to patch it back together in some cases, but audio would be a whole different process.

Again, good luck with this as it would be interesting to know if you find something that works. All programs use their own format to create a file like a recording, and so you'd need a program that can understand the raw data of this type. Even if you are able to retrieve a recording, I wonder how good the audio would be.
 
Of course, I'm sure you know, if you write anything to that hard drive, the wave files you are looking for probably won't be found. They are marked for deletion and overwriting, as far as the computer is concerned. So, if some of that file you are looking for is overwritten by another file, I doubt you'll end up finding much of anything.

I think you said you had put in a different drive for your tests on this. This is very smart.
 
yes!!!!! :), I managed to find the audio. With "audacity" I imported in "RAW" the .AA image that I created with "clonzilla" of the MX2424 hard drive. "Audacity" asks me the type of audio file so I informed him saying that it is "mono" 44.1khz and 24bit. after 8 minutes of total import of the sector disk by sector I find in "audacity" a waveform in "white noise" and in some place of the zones with an audio wave. I listened in these areas and I found the audios of the whole concert. I exported as a wav file and I will have to organize this file because currently I have all the tracks by end of 3 seconds assembled. ( Like this : exemple: 0 second to 3second track1 then 0 at 3s track2 then 0s at 3 s track 3 ...etc then 3 second at 6 seconde track 1, then 3 at 6 s track 2 ect... normal because the mx writes every 3 seconds the audio of each tracks of the recordings on the hard disk and when the recording is stopped it assigns these mixed data to each of the wav files.)

this is good news, but I have a noise quantization in the audio, and I think it comes from "audacity" because I tested by importing in "RAW" a file "wav" in exellent state located in the hard drive of my computer is I have the same noise.

who knows why I have quantization noise even when importing a file in excellent condition?
 
Great to hear that you have recovered some audio.

Just a note, when recording a live show it is always advisable to record in tape mode as there is less chance of fragmented wav files.

Cheers
Alan.
 
Hi,

so now that I know that "Audacity" can read all the binary content of the disc through a total image of the disc, I look for why there are errors with a significant quantization noise. We can think that this is because the data is damaged, and yet I tried to import "WAV" data of the same type in perfect condition and there are also errors. I have however indicated at " audacity" the type of audio content that it is ..

as long as the recovered audio contains white noise, it is not exploitable, so I do not need to rearrange the audio data.

If I manage to import the audio quality I would look for a technique with 2 hard disk to try to make a finalization on audio file found and exchanged and thus have the audio reorganized naturally.
 
Hi,

so now that I know that "Audacity" can read all the binary content of the disc through a total image of the disc, I look for why there are errors with a significant quantization noise. We can think that this is because the data is damaged, and yet I tried to import "WAV" data of the same type in perfect condition and there are also errors. I have however indicated at " audacity" the type of audio content that it is ..

as long as the recovered audio contains white noise, it is not exploitable, so I do not need to rearrange the audio data.

If I manage to import the audio quality I would look for a technique with 2 hard disk to try to make a finalization on audio file found and exchanged and thus have the audio reorganized naturally.

It's a long shot but VLC offers the same raw import>save as option.
Maybe it'll do it better?
 
Hello, I tried again with "Audacity" and this time currieusement I found all the audio and in perfect quality. The mysteries of computing, strange. So I exported with "Audacity" as a .WAV file and I imported this file into the MX 2424 and then I assembled all the extracts of 2,967 seconds sets and on each corresponding tracks. that asked me 1 hour for 10 minutes of music. 1000 editions in average per hour and with an assembly to the precise audio sample. I now have my concert restored on the multitrack session and I will be able to work on the mix ..

I also tried to do this organization by the mx 2424. I took 2 identical hard disk, one containing the unreported audio and the other on which I run an empty recording of the same duration with a project to create with the same name. Then comes the moment when I stop the recording I connect very quickly and in operation the hard drive containing unreported audio instead of the other hoping the MX 2424 writing the finalization on the disc containing the audio no listed, hoping that it organizes the files. the experiment was a failure, the MX is blocking itself.

So I made me the re-organization in edit mode.

the story ends well.

Thank you for your help.
Chris
 
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