DSL40cr . I'd like to plug in a 2x12, 4 ohm cab into the  4 ohm output and leave the existing 16 ohm internal connected to it's original 16 ohm position. Is this ok?

In other words(back of the amp) the 4 ohm cab would be far left hole, and 16 ohm internal, far right hole, all at the same time. Good to go ?

Thanks, Dan