Vox AC30CC2 Owners - Output Impedance

[earth tones]

I just picked up a Vox AC30CC2 and the previous owner has installed 2 16-ohm Greenback speakers. They appear to be wired in parallel and the Output Impedance switch on the amp is set to 16-ohm (rather than 8). The parallel wiring of these speakers would preset 8-ohms of impedance, right? I want to be sure before making the change, and I'm wondering what kind of effect playing the amp in this configuration (if it does so happen to be set incorrectly) can have electronically and sonically. Are the speakers technically capable of working the amp harder than it is set to operate?

[Nathangrn]

An impedance mismatch of this magnitude shouldn't hurt the amp or the speakers. It may make it marginally less efficient. Since you have a switch to correct the situation you might as well set it for 8ohms.