I have a 07 sedan, without the Bose system.

I know we can install a hi/low level converter on existing speaker wires to get RCA outputs for an amp.

My question is will this change the ohm impedance? I don't want to install this and cause any problems with the factory head unit. (Sorry if this is a dumb question, I just want to be safe before I start messing with the factory system)

Thanks for the help