Since Xenon2 was first released for the Amiga, I found the original Megablast track in the .YM section of chiptunes, YM coming from the name of the Amiga sound chip.

Next was the problem of how to play it, as none of my players/trackers could play it. Fortunately because chiptunes is such an excellent site, it was easily to fine a solution: Someone has written a WinAmp plug-in that enables you to play .YM files. I've provided the plug-in here to save you the bother of finding it in chiptunes, though you should still go there as it's a great site.

So I downloaded it, put the .DLL in the WinAmp "Plug-Ins" folder, and lo and behold - I had the wonderful soundtrack blasting out (if, as to be expected, it was of slightly poor quality). I also downloaded another WinAmp plug-in, MP3 Output which lets you convert any other sound format to MP3 in WinAmp. So I converted it to MP3 for you as most people these days have some kind of MP3 player - see, I am nice aren't I!
Here it is just for you: Xenon2-Megablast.mp3 (766kb).

Actually, because the .YM WinAmp plug-in can't determine the length of the .YM file, it plays forever, and so the MP3 Output plugin wasn't much use - I used the Disk Writer plug-in to convert it to a .WAV up to the point that I thought it repeated first and to keep it small (YMMV) and edited the .WAV file to trim off the excess before converting it to MP3.