Man... i'm 15 year old and I got a Nokia 7650... I had 4Mb memory and I'm using Ultra Mp3 player... I got 2-4 mp3s on my phone... so........ to use mp3 on Nokia 7650 U need to encode it to 24Kbps an 22Kh... in this case the mp3 is 500-600 Kb... :P
Well, i am currently using 7650 with MP3PLAYER (vikinggames.hu) with 2 mp3 on it and about 1M free.... I am using MP3 RM Converter (audiotoolsfactory.com) to convert files form mp3, ogg to compressed mp3. You need to convert song to 1600Hz and 3kbps in order to have a 3 minutes song in 800 kb.......