how to monitorinf Surround files ue4

I am a sound designer. I am very inexperienced in ue4, and have been reading that labeling the audio files as: _surround_fl, fc,fr etc Ue4 recognize them as surround sound.
So far all right, now someone would know I say because when I do a playview of the project, whether I use Oculus Rift,or if I monitoring with multi-channel speaker system I don’t feel of envelope?
If someone have any idea about, i’m glad to share.