Hey there, this is pretty typical. Lots of buyers like to run two separate pairs of speakers, but you don't have 2x the circuitry. The jacks are just there for convenience.

The lower the impedance number, the harder to drive.

The top line means "A or B" - each speaker can be rated no less than 4 Ohms.

The bottom line means "A _and_ B " - Each speaker can be no less than 8 Ohms.

The lower the impedance number, the harder to drive.

The top line means "A or B" - each speaker can be rated no less than 4 Ohms.

The bottom line means "A _and_ B " - Each speaker can be no less than 8 Ohms.