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Author Topic: Edirol R-09 >2GB Issues, 4 byte shift solution + partial 4 byte shift oddity!  (Read 3126 times)

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Offline earthkiss

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I've come across two issues with recording over the 2GB mark on a Transcend 4GB file with firmware 1.03 and found two solutions I'd like to share.

1) I recorded a band rehearsal in a number of large files. The last file began past the 2Gig mark on my 4Gig card as follows:

0GB [1st part | 2nd part | 3rd part | 4th part] 4GB

So to clarify, the first 3 files had their headers under 2GB and the 4th file had it's header somewhere past 2GB.

The 4th file would not playback on the R-09.

It transfered to the PC fine both with an external card reader and over the internal USB connection.

The file had a corrupt header and played as white noise in winamp and also looked like white noise when loaded as a raw file in wavelab.

The solution was to add an additional 4 bytes to the header specifying the size of the data chunk in the wave file.

A 1 byte shift appears to work as previously mentioned in a prior post but this solution swaps around the left and right audio tracks.

The procedure is as follows:

i) Load the file into Ultraedit
ii) Find the word 'data' near the begining of the file and insert a 4 byte value corresponding to the size of the file from the point after the 'data' marker to the end of the file.
iii) Optionally adjust the 4 byte file size value, which is now 4 bytes too short, after the 'riff' marker at the beginning of the file, to equal the size of the entire file. This can also be achieved by using wavelab or similar to resave the file, thus causing a new header with the correct file size to be written. This is optional as the file seems to still play correctly in this state.
iv) Find a simpler way to do this than Ultraedit and let me know!

2) This is a bit odd...

I got cocky and on a freshly formatted 4GB card put a few mp3 albums and continued to record live gigs.

At some point I also expanded a compressed cd in flac format to wav, on the actual card.

This resulted in the following on my card just before the anomally:

[mp3 cd | SPACE under 2GB | wav cd | live gig set 1 | live gig set 2 | Space over 2GB]

With the card in this state, the anomalous recording was distributed on the card bothe under and over 2GB.

The resulting file would not play on the R-09.

It coppied to the pc fine.

It also appeared to play fine in winamp, but about half way into the set I got white noise.

Examining the file in wavelab showed the file had recorded correctly upto about half way and then HISSSSSSSS.

I then tried loading the file into wavelab as a raw file and the first half became hiss and the second half appeared uncorrupted!

With a data offset of 4 when loading as a raw file in wavelab, the situation reverses with the first half being ok with the second half corrupt.

I thus did what was neccessary to join the two halfs together as accurate as I could by zooming into the pixels in wavelab.

I few seconds of recording appear to be missing.

So my guess is that when recording, if the file writing code needs to jump over the 2GB point, as opposed to simply passing sequentially, some sample data is lost and also the file pointer code screws up and puts the data 4 bytes out of sync?


Just thought I'd share my findings with you as I've found your forum very helpful and just though I'd give something back.

Offline lbgspam

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Thanks! I added this post to the R-09 FAQ! :)

+T for you!

 

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