I am importing raw data from a corrupt wav file.
The file is Signed 32 bit PCM @ 48000.
I can get the import to work but the file plays back too fast. Like the SRC changed the playback speed?
Audacity 2.0.3
Windows 7 Pro SP1 64 bit
Doesn’t the raw import give you the ability to select the sample rate? You picked the wrong one. Once it’s on the timeline, you can use the drop-down to the left and change it there, too.
Koz
I’m going to write this down. You may be the only person who ever got Import Raw to do anything useful.
Koz
It took me a while to get import raw to do anything useful for sure 
These files are from a multitrack digital recorder. Some of the files are fine and some corrupt. I suspect the corrupt files were not closed correctly.
All the files were recorded 48K 32bit float.
But to get the files to import at all, I had to choose the Signed 32 bit PCM codec in audacity NOT the 32 bit float codec. I thought that was weird?
I will double check with the recording engineer, at verify the 48K recording sample rate.
If the files are not private, you can post a link to one of them. We might be able to use it as an example when we work on Import Raw again.
Gale
If you call the engineer and they say it was 48000, then…full stop. We stand around looking at each other drinking tea.
You can try Effect > Change Speed or Effect > Change Pitch, but those tools add distortion. It’s much more likely just changing the sampling rate will return the performances to normal with no further fuss. On the other hand, if none of the sampling rates work, then you have damaged tracks, but you already knew that.
Is this a DAT machine by any chance? Those are 48000, yes. They’re video standard.
It’s a standing joke that you always take a backup recorder to a DAT shoot. When you get back home, throw the DAT tape away immediately and use the backup. Chances are overwhelming good the DAT tape is trash and you can save a lot of time assuming that right at the top. If it was a Very Important Shoot, it’s 100% certain the DAT tape is trash.
koz
It is a 16 track digital recorder straight to USB stick. Cymatic Audio LR-16
These tracks are from a live show of a local band. Mostly original songs. I will check about posting one here.
I will check about posting one here.
But you didn’t try a different sample rate?
Koz
You will not be posting a song on the forum. We’re only good for about 12 seconds of WAV music depending on the sample rate. You’ll also need to post a regular song so we know what “normal” is. An open posting on DropBox or other file service would do it.
https://forum.audacityteam.org/t/how-to-post-an-audio-sample/29851/1
Koz
I found out it is possible for it to work.
The very first export I did to mp3 was actually correct and played back normally.
I just have to figure out the combination of raw import sample rate vs. session sample rate.
“Not closed correctly”…
Do you think it is the recorder not closing files or did someone pull the USB key without powering down the recorder?
If it’s the second case, a good disktool might be able to repair the USB key.
Here’s another possible solution.
I had a number of corrupt files from a audio recorder. I could not figure out the raw import settings. I found a python script that read the wav header from a good file. This program said the BlockAlign size was 2048. I then extracted the first 2048 bytes from a good file and created a new header.wav file. Then I appended the bad file to the header file. Audacity read this combined file and played it normally. There was about o 1/4 second of junk at the beginning, which easy to delete.
If you can find or guess the alignment size and start with a good header, Audacity seems to play corrupt files.
I found the python script here:
http://blog.theroyweb.com/extracting-wav-file-header-information-using-a-python-script
I used gnuwin32/dd and copy /b [windows] to extract/combine the files, but other utilities will probably work fine depending on the platform.