Assertion: sounding board | /r/CapableOf | extend to adjacent the top of the back frame
Facets:
Source sentences:
text: In an upright piano structure, a back frame, a string plate carrying piano strings thereon, a pin block mounted adjacent the upper edge of the string plate, and a sounding board secured to the back frame and positioned between the back frame and string plate with the upper portion of said board spaced from the pin block to permit free passage of sound waves therebetween and extending to adjacent the top of the back frame substantially coextensive with the pin block and the upper portion of the string plate.