Keyboard musical instrument having keys equipped with...

Keyboard musical instrument having keys regulated with...

Keyboard musical instrument having keys regulated with...

Keyboard musical instrument having regulable regulating buttons

Keyboard musical instrument having sloped top surface

Keyboard musical instrument having split rear top board...

Keyboard musical instrument having top board coupled with...

Keyboard musical instrument having top board coupled with...

Keyboard musical instrument having variable contact point betwee

Keyboard musical instrument performable without noise in silent

Keyboard musical instrument selectively introducing time delay i

Keyboard musical instrument structure

Keyboard musical instrument with casing comprising two halves

Keyboard musical instrument with fallboard located at proper...

Keyboard musical instrument with keyboard range indicator

Keyboard musical instrument with laterally adjustable...

Keyboard musical instrument with movable key bed for performing

Keyboard musical instrument with removable box leg

Keyboard musical instrument with simplified key unit assembly

Keyboard musical instrument with solenoid-operated actuators arr