Play some music you know that has good bass (make sure your speaker cables are connected correctly). Flip the switch and listen for any change to the bass. whichever position has the most bass is the correct polarity.
Invert ?
I’ve owned the Audio Research Ref 6 SE for about a year or so. One thing I don’t understand is the Invert switch. What is this used for exactly. The manual doesn’t not go into detail at all. Actually I’ve always been afraid to use it thinking I may damage something. Thanks in advance