^ That link doesn't work anymore.
Luckily, I kept the installer for the Xbox codec when I downloaded it a couple years ago.
So, I decided to upload it to FileFront for anybody who wants it:
http://www.filefront.com/14276197/XBADPCM.zip/Make sure to follow the instructions. This codec has worked perfectly fine for me, although I'm running XP so I can't say whether it will work okay on Vista or Windows 7.
I decided to write a short tutorial on how to properly compile sounds with Tool. A lot of people seem to rely on the Sound Converter, and it sometimes causes problems. With Tool, you shouldn't have any problems with sounds as long as you know how to set them up correctly.
All sounds have to be Signed 16 bit PCM Wave files. For mono sounds, the sample rate should be 22050 Hz, whereas it should be 44100 Hz for stereo sounds.
If you want a sound tag under 'tags\sound\music\epicmap\' called "intro.sound", then you need to create a folder under 'data\sound\music\epicmap' called 'intro'. The 'intro' folder under 'data' will be the 'intro' sound tag under 'tags'.
This is because whatever sounds are inside the 'intro' folder will become the permutations of the 'intro' sound tag. As a result, the 'intro' folder is treated as a sound tag.
In the case of music, you only want one sound in the folder, which is the whole song. In the case of dialog or any sound effects, you can make multiple recordings and stick them in the folder, creating different permutations to randomly choose from.
So, place your 'intro.wav' sound file in the 'intro' folder. The name of the .wav file will be the name of that permutation in the sound tag. They don't have to match.
Now, when you specify a folder for Tool to look for sounds in, remember that each sound is actually a folder. So, in this case, you don't want to specify the 'intro' folder, but the folder above it, which is the 'epicmap' folder.
You can put as many sounds as you want under the 'epicmap' folder, and Tool will compile all of them, i.e.:
data\sounds\music\epicmap\intro\intro.wav
data\sounds\music\epicmap\middle\middle.wav
data\sounds\music\epicmap\ending\ending.wav
In the case of multiple permutations for, say, dialog, one sound tag setup could look like this:
data\sound\dialog\chief\hurt friend\1.wav
data\sound\dialog\chief\hurt friend\2.wav
data\sound\dialog\chief\hurt friend\3.wav
In which case you would specify the folder 'sound\dialog\chief'. This would create a sound tag called 'hurt friend' with 3 permutations: '1', '2', and '3'.
Finally, here are the commands to compile using Tool.
For Xbox format, use this:
tool sounds sound\music\epicmap xbox 1
For Ogg format, use this:
tool sounds sound\music\epicmap ogg 1
For music, make sure to check the 'split long sound into permutations' box at the top of the sound tag and then recompile. You could also create the sound tag with Guerilla and check that box before compiling. Even if the song is shorter than the limit, it's best to split it up anyways.
On a side note, although I've used the Xbox format without a problem, it tends to result in larger file sizes than the Ogg format without any increase in quality. It's best to use the Ogg format. After all, the majority of default Halo sounds used Ogg.