Considering the 502 has no XLR ports, the answer to your question is no, it can't be done with XLR cables. But the 502 does have a tape loop RCA connectors and the 166xl does have 1/4 inch TRS connections. You should be able to find cables that could allow you to put the compressor in the tape loop. I don't know for SURE that will work in your application, but I think it will.