Unlike the standard Nook and all Kindles, the PRS-650 let's you organize and select songs using the embeded MP3 ID3 Tag information. This is the way most of the higher end MP3 players work.
The above procedure strips these tags out of the MP3 files, so as suggested be sure to do this only to copies, and preserve the original MP3 files somewhere with the ID3 tags intact.
Loading the files after the tags are stripped causes the PRS-650 to fall back to using file names only, and to just group all the untagged files together under "unknown".
If you want to try an even slicker trick, download a copy of a free MP3 tag editor like 'MP3TAG' and use that to edit the tags to create custom 'play lists'.
The Sony doesn't have direct 'playlist' support, but we can fake it by making a copy of the files we want in each playlist in a separate folder, and then editing the 'album' and 'title' tags to fool the PRS-650 into grouping the files the way we want.
Once you figure out how to use the MP3TAG editor to change TAGs it's really simple.
Copy the current name of the album from the 'Album' tag field and paste that in front of the current song title, then edit the album ID3 Tag to something like "Playlist 1" or "classic rock" (or anything else you find handy, just make it the SAME for all the songs you want grouped together) Then change the "Artist" Tag field to "Various".
So for example if the Tags for the songs start out like this -
Album = White Album
Title = Back in the USSR
Artist = Beatles
Then you would edit the MP3 tag fields to look like this -
Album = Classic Rock 1
Title = Beatles - White Album - Back in the USSR
Artist = Various
The advantage of the above method is that by changing the file name and tags slightly you can have multiple tagged 'playlists' plus full album versions on your Sony at the same time.
As long as the ID3 tags and filenames are changed, you can even have the same song loaded in several tagged playlists, plus as part of a full album.
Of course this physical file copying and duplication burns up a lot of Flash Memory space, but that's what those big 8 and 16 Gig SD cards were made for.
