As an Audio Editor and Sound Designer, I understand your requirements. Assuming that the audio has some background noise and does not sound very appealing in totality, I will eliminate the background noise if there is any, and tweak the voice-overs so that it sounds fuller, crisper, well balanced and as natural as it can get. I hope this is what you are looking for, if not then please feel free to share your ideas. Looking forward to great Voice Overs for your website. Have a nice day.