How do I convert mp3 to RIFF?

First of all if your making a kiai / hitsound the file needs to be in .wav format not .mp3
and needs to be less than 5 seconds long
For Conversion and making of the sound i recommend a program called Audacity
I hope this has helped you ^-^
(P.S. If you can still not figure out how to make the sound you want send me a Pm and i will make you a sound for free ^-^)

Thanks dude