These torrents included all the tracks that could be previewed on the SXSW website for SXSW 2011. This year's collection included 1,154 files totaling 6.58GB.
The first torrent was seeded February 7, 2011 and the second on March 7, 2011.
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Disclaimer: This site is in no way affiliated with SXSW or any SXSW artists. These torrents are provided as an alternate means to sample the songs available on the official SXSW site.