I just purchased a used Kawai BS-10 piano but I realized the back panel where the soundboard is does not have any vertical wooden frame at all. Although the staff assures me this is typical of BS-10, I just can't get over it as all other brands or models have some form of vertical frame or cross frame
I tried to search photo of BS-10 soundboard/back frame photo but to no avail.
Hope someone can help me here. Thank you in advance.
The diagonal strips are called Ribs they transmit sound across the grain on the soundboard and support the crown
Web Master UK Piano Page
If braces are absent from the rear of the piano, surely the frame must be supported somehow from inside the cabinet, presumably the sides. I think I would be more worried about the absence of ribs on the soundboard. Is it possible that at the back of this piano is covered with a wooden panel ?
Photographs of the rear and the front of the frame with the cabinet front removed would perhaps be helpful (?).