Full Length Ribs Yamaha reinforces the crown in its soundboards by using ribs that continue to the edge of the soundboard, and are glued into the notched liner (or inner rim on the grand piano). Reinforcing the crown ensures that the tone quality will remain for years and years and improves tuning stability. V-Pro Plate Yamaha uses V-Pro (Vacuum Shield Mold Process) in casting the iron frame (plate). V-Pro plates are stronger and visually more appealing. Critical dimensions are produced more accurately than before. Metal Action Rails Yamaha engineering developed a unique Extruded Aluminum Alloy Action Rail (bearing a Yamaha patent) that is one of the best innovations for improving a piano action in the last 100 years. The usual fluctuations in wood rails that effect touch, caused by periodic weather changes, are eliminated allowing stable, long-lasting action regulation. Balanced Action Each key of a Yamaha piano is individually tested and measured for the corrections needed to obtain uniform “down weight” pressure. Yamaha actions play correctly and uniformly. This balancing helps ensure a lifetime of superior touch and control across the keyboard. Uniform Key Travel Yamaha designs all grand and vertical pianos to have the same key travel. Regardless of size, type or model of Yamaha piano, the Keyboards will always feel the same. Spruce Keys Yamaha uses Spruce for the keys on all models of pianos. Spruce is very light and possesses a very high ratio of strength to weight. It is ideal for key construction, even though its cost is greater than either sugar pine or bass wood. Yamaha keyboards respond quickly providing fast repetition for the most intricate piece of music. Yamaha keyboards withstand heavy use over years of fortissimo passages.