Someone mentioned bridged load into 8 ohms in the manual. Need to spend more time learning about this. Glad to hear I can bridge 4 ohm speakers. Want to see if it makes a difference like going from MAC4100 to MC7200. Still thinking of a more sensitive speaker. Legacy Focus and some one who worked at McIntosh mentioned Omega. Still looking hoping to find used but will take some time as it seems shipping can be a problem.