Hi all thx for having me join this forum. Last year, after many years of playing, a boyhood dream finally came true, I got myself a Marshall half stack, a JCM900 4100 with a 1960A. Both my 1979 Strat and 2013 LPR8 vos sound awesome and allow me to mimic the brown sound, somewhat. It took me about a year to realize there was something odd with how I was told to connect the amp to the cab. I bought the set of someone whom told me to connect it in this fashion and it has been working fine. The speaker cable is connected to the 4 Ohm input. But the amp selector switch is set to 8 Ohm, as if it was a stereo connection? See included . As I want to connect the amp to another cab, I need to know for sure what is going on. It is possible the tech of they guy I got it from (whom I cannot reach anymore), made some mods causing this weird way of connecting it? Could there be any harm in connecting it the proper way, selector at 16 ohm as well as speaker in 16 Ohm input? And then trying it on very low volume? Or could this potentially damage the amp?