How to force stereo to 5.1 sound

I would like to hear mp3 songs in stereo permanently in 5.1 sound what do I have to set?

Please help me somebody

THANKS

Use K-Lite Mega. Do advanced install.
During install select MPC-HC as preferred player.
On the "Select Components" page enable "ffdshow audio processor" (use automatically in MPC-HC).

Then after install, open settings of "ffdshow audio processor". Enable Mixer with option to "expand stereo".

Thanks Admin