This is not a copied tutorial, completely done from my own testing done tonight.
Before you do anything, back up all your MP3s you intend to play with. I take no responsibility.
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Converting MP3s to Gapless: Using Windows, Lame.exe and Foobar2000
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* Download Foobar2000 from http://www.foobar2000.org/
* Get Lame.exe from http://sourceforge.net/project/showfiles.php?group_id=290&package_id=309
- Next, install Foobar. It should be in Start > All Programs > Foobar2000
- Open a bunch of files (File > Open) and they should appear (make a backup!)
- Right-click on each one and choose Utils > Edit Gapless MP3 Encoder Information
- Change the top number from 0 to 4095 and click OK. Do it for each one.
If you know anything about how binary and bytes work, then you'll know what 4095 is close to. If not, one megabyte is usually said to be 1000. But really, it is 1024 and that comes to 4096 (1024x4=4096). That's a bit of maths for you all.
Then get Lame.exe and save it. I saved it to My Documents, which is where all my crap goes.
Back in Foobar, press Ctrl+A to select all files and right-click. Then choose Convert > Convert To. Click OK and ignore the lossy warning (obviously lossy as MP3s are), choose where the Lame.exe file is as Foobar will ask you (should be where you put it where I wrote:
Then get Lame.exe and save it. I saved it to My Documents.
Then when that's found, choose the Output Directory (My Music is best) and the files should save. Go to Media Player or iTunes, add the files and play them. They should now be gapless. I hope it works for some of you, as it has for me.