The action of every Blüthner piano is a complicated system of levers, which has been meticulously developed and refined by the Blüthner factory over the last hundred and sixty five years. The Blüthner action responds easily and is precisely balanced to give the pianist complete control over the musical expression. Blüthner hammer heads are made from the finest felt, and carefully cold-pressed to perfectly protect the elasticity and other important characteristics of the felt fibers. Blüthner hammers can be recognized by their Blüthner blue underfelt.

All Blüthner grand pianos, with the exception of the smallest baby grand model, feature a unique fourth string, called an “Aliquot”, which was originally patented by Julius Blüthner himself in 1872. This has always been a proven and heralded innovation in piano design and a key source of Blüthner’s well known warm and romantic sound. The Aliquot is stimulated to sound through the resonance of the other three strings beside it, enhancing the harmonic spectrum. This unique effect produces a dynamic sound, which is audible over a wide range, and defines the resonant treble of a Blüthner piano, adding color to the high treble register.

The iron frame of every Blüthner piano has been formed by a wet-sand cast iron process, before it is filed, hand-milled and sealed to protect against corrosion. The plate finish is a special bronze compound. Its design has been carefully calculated and uniquely crafted for each model in order to securely bear the enormous load of nearly 20 tons of string tension exerted within a grand piano tuned to concert pitch. The name of the firm has been cast into each Blüthner plate.

Each string on a Blüthner piano has been drawn by hand through exact diameters measured to a one-hundredth of a millimeter, and individually tied off for precision. The bass strings are hand-wrapped at the factory, and formed around a hexagonal center-wire to ensure the tightness and longevity of the copper wrapping.