Reducing Bit Rate

Is there a way to reduce the bit rate of a file. I always copy albums to MP at 192 Kbps, and will only DL at least 160Kbps.
I have just DL an Albumwrap at supposedly 770kbps (each track 10mb). I would like to store these on Win MP but at 192 if possible. Is there software to convert down to the smaller bit rate.
I DL a file supposedly at 770 (each file is 10mb double the size of a file DL at 192) I would like to store it at 192

just re-encode them, u can use dbpoweramp music convertor.

http://www.dbpoweramp.com

Thanks, I will try that