The Knight iron frame offers twice the strength of those in an average piano. It is a full-perimeter frame built on a girder principle that is secured to a four-post beech back. The pin block is fitted in a pocket cast into the frame for exceptional tuning stability.
There is no treble stress bar in the K10 model. Several resisting bars are cast in the bottom left-hand corner of the piano to resist the strings’ tension, eliminating the possibility of weak-sounding notes.
Hard fiber plate bushing are used to support the tuning pins to enhance tuning stability. The bass strings are covered with extra heavy pure copper, giving a total weight of 7 lbs(3kgs) a set.
Dates and serial numbers when the pianos were manufactured