First thing you need some kind of WAV editing program. Personally i use Cool edit 2.0 for this:

1) load your MP3 or WAV you want to convert.
I took an MP3 of 3 min 41 sec which was 3.37Mb in 128kbps encoding

2) Convert and resample it to 16000Hz 8-bit Mono
For cooledit 2.0 the option is edit menu on the bottom, or you press F11

3) Save the result into GSM 4:1 encoding
For cooledit the option is in FILE | SAVE AS, then choose as type ACM WAVEFORM, then choose OPTIONS and choose GSM 16000 MONO from the drop down box

The result for my 3,5 min mp3 was 704kb, that fits easily on the phone and sounds great on the internal speaker, ideal for a ringtone.

Of course you don't need all the song, cut and paste using the program and try to make repeating loops, sounds great. Most smaller loops are just as big as a MIDI file.


Feel free to post remarks or correct me where i am wrong.