If you don't follow FCH's instructions. This is what I posted several days that might help you:
You can add chants just like you would add a song. You need to import the adx file using afs explorer 3.4. The chant adx's begin with SP. For instance, Premiership chants begin with SP_0100.
Firstly you need to obtain a wav or mp3 file of the chant. If you search the internet you should be able to find some.
Then follow Pablo_el's instructions:
a}open mp3 with Nero Wave Editor select save as, options and set frequency to 24000 [save]
b)move the file to adxtools folder and move the folder to c
c)klick start/run enter cmd type cd\ [enter] cd adxtools [enter]
d)type adxencd filename.wav [enter]and this text would appear (the **** is string of numbers diffrent for each file)
Input sound data file: 'filename.wav'
ADX Compressed data file : 'BGM_01.adx'
Sampling frequency : 24000 Hz = Input sound data
No. of channels : 1
Input audio sample : ****** smpl = 120.0 sec <24000 Hz>
ADX output sample : ****** smpl(Blk:****** smpl) = 120.0 sec <24000 Hz>
e)type adxencd filename.wav -lps0 -lpe"******" (quotations marks needed!)
f)open adxplay and check if the file plays correctly and loops
g)import the file with ASF Explorer. You may have to rebuild 0_sound.asf
If you need any more advice just let me know.