The Steinway Soundboard
One of the most important factors in determining which piano is right for you is: Sound. In this article we will discuss what make the sound of a Steinway piano standout from other pianos.
More than 98% of performing pianists insist on using a Steinway piano. Why this dramatic vote of confidence? The main reason is the tremendous diversity of tone and color that can be created only on a Steinway. The sound of the Steinway piano is one of power, warmth, richness and color. This tone is the result of many exclusive features, some of which we’ll now discuss.
Integrity of design, materials and workmanship is maintained in the creation of all Steinway’s. Each aspect of this threefold foundation plays a role in the instrument’s superior tone.
The “warmth” of tone in Steinway grands and uprights is partly due to the “wood to wood” construction techniques. Maple dowels are used instead of metal screws throughout the instrument. The cast iron plate sits upon maple dowels instead of large metal nuts. Since the entire piano contributes to the sound quality, metal to wood connections are avoided. In addition to enhancing tone, this approach is simply good wood workmanship, increasing the instrument’s longevity and durability.
Another major factor in the Steinway’s superior tone is the piano’s speaker system: the soundboard.
About the Soundboard
Sitka spruce is the most resonant wood available. Soundboards in Steinway pianos are constructed from solid (never laminated) Sitka spruce with annual growth rings measuring 8-12 per inch. These close-grained lines enable the sound-producing energy to travel to the end of the board, which is custom-fit to the top of the inner rim. The energy travels more efficiently when the soundboard is close-grained, just as a large volume of cars travels more efficiently on an eight-lane freeway than on a two-lane road.
This is just the beginning. When the sound-producing energy reaches the inside of the single-bent hard rock maple rim, it instantly returns to the body of the soundboard, where it resonates. The efficiency of this process is much enhanced by the hardness of the rim, which is constructed from hard rock maple.
If we compare the sound-producing energy to a ball and the rim to a wall, we can see what happens. When the ball is thrown against a soft, thin wall it does not bounce back quickly or with much distance. Similarly, when a note is struck on a piano whose rim is made of inferior materials, (softwood) the resulting tone has neither projection nor power.
But if the ball is thrown against a thick (hardwood) wall (the piano rim’s hard maple) it will bounce back past the thrower – almost before he/she has completed his throwing motion. This picture reveals why a Steinway piano can be heard above a symphony orchestra without the aid of a microphone.
We still haven’t finished. Each Steinway soundboard is fit to a specific piano – i.e., each soundboard is custom-made. The perfect fit increases its efficiency; there is no wasted energy (power).
The final factor is the soundboard’s unique shape. The greatest thickness is in the middle, from which point there is continual tapering in all directions toward the outer edges. To understand this Steinway-exclusive “Diaphragmatic” design, which is found in all Steinway grands and verticals, let’s consider an illustration.
An Example of How a Soundboard Works
Imagine a small pond with a bridge across the middle. When a large rock is dropped into the water from the middle of the bridge, waves are created. The initial waves will be large. As they move away in all directions from where the rock landed, though, they will decrease in size. (This happens according to the law of physics that energy diminishes when it meets resistance.) By the time the waves reach the shore they will be quite small, as there will be little energy available to move the water.
This is how a soundboard works. The rock-dropping occurs when keys are struck. The large splash is the initial explosion or projection of tone. The diminishing waves are the sound as it travels through the soundboard in all directions away from the bridge. As there is less energy to move the water (make waves), there is also less energy available to cause the soundboard to resonate.
How to compensate for this natural phenomenon?
As noted above, Steinway’s Diaphragmatic design specifies that the soundboard become thinner at the edges (The Steinway Diaphragmatic Soundboard is 8-9mm in the center tapering to 5-6mm at the edges. This design reduces the energy needed by the soundboard to vibrate, an efficiency that permits a greater variance of tone color and richness.
The Steinway’s rich tone is due also to the full (front and rear) duplex scale design. The design allows for the fretted “non-speaking” lengths of the steel strings to vibrate in sympathy with other notes being played. This feature would contribute little, though, if the soundboard were not sensitive and efficient enough to respond to subtlety. Without the Diaphragmatic soundboard, the tonal attributes created by the duplex scale design would be like words whispered to someone with earplugs.
The design, shape and materials of the Steinway soundboard make it the best found in any piano, at any price.
As you can see there are so many details that go into building the soundboard for Steinway. This helps explain why it takes a full year to completely build a Steinway.