There is a completely free program that works also.
Audacity does a great job, the only limit I have found is it does not handle a two hour long audio file. (It crashes when converting).
http://audacity.sourceforge.net/
I am sure there are others.
Carl312: Windows 10 64-bit 8 GB RAM,AMD Phenom II X4 965 3.4 GHz,ATI Radeon HD 5770 1GB,240GB SSD,two 1TB HDs.