Convert optical audio into 5.1 rca(or xlr) connections.?

XLR are mainly use in high end audio Equipment and microphones. I use XLR cable for my pre amp to the power amp connection, and they are also expensive 1 meter for $150 each. There is no point in converting a multi channel signal to a stereo signal, beside that the optical connections is digital and XLR is a balance stereo signal. I have not seen any speakers with XLR type connection even in the very high end audio. Your speaker is more than likely a 1/4 inch plug, which is used on most commercial use like DJ. Hope this will help you out.