Opening .xwv files

[Raccoon Sam]

I would've never guessed that 'cause I don't know anything about audio files pretty much.

Well, even if I knew nothing about audio files either, the first thing I would've done was to Google the bytes and immediately be greeted with a WAV file format specification page.
Even if you know nothing, it's always a good idea to first open the file in a hex editor and look at the first bytes. If they give no insight, Google the bytes. If that doesn't help, then ask the fine folks here.