Thanks, @Bob. If I tuned the dulcimers right, banging on the wall might create a nice sound. But I think right now, the Probst baritone is tuned to A, the Blue Lion to C, the baritone dulcimette to G#, and the Beede octave to high D. It might sound like an orchestra tuning.
What a lovely musical wall arrangement! You have a nice artistic eye.
I wonder how it would all sound if you bang real hard on the wall?
Dulcimers from left: a Blue Lion IC, an Eedy Beede octave dulcimer, a Ron Ewing octave dulcimette, and a Rick Probst dulcimer strung as a baritone. Four dulcimers, four tonal ranges. The artwork from left: a photo of Pete Seeger's banjo, a print of "Kandinsky's Dulcimer" by FOTMD member @Wayne-Jiang, and a wax pencil drawing by my mom of me with my guitar and my niece.