Advice wanted for small factor office speakers

I am helping a small business owner set up office speakers. Mostly in waiting area and hallways for background music. Speakers will be passive, mounted high on walls and wires run over drop ceiling to a Pyle multi-zone amp. They will be run in mono, not stereo.

Any suggestions for mountable, good sounding speakers? Looking at Yamaha, Klipsch, Polk and Pyle brand. Does anyone have any experience or knowledge with good sounding, nicely built passive speakers?

(I have ruled out Sonos powered speakers since it’s not easy to run AC cords to powered outlets.)