Piano construction (components)

Piano construction (components)

Why does a C. Bechstein grand piano sound so good? Here we reveal some secrets of piano manufacturing and insights into the special features of C. Bechstein production.

C. Bechstein: Its sound is legend

The sound of a C. Bechstein instrument is legend. It is incomparable, clear, transparent and colorful. C. Bechstein grand pianos are extremely assertive and have a verylong lasting and transparent tone. On the other hand, these instruments are characterized by their lyrical, very cantabile timbre that blends together with strings and singers wonderfully sensitively and empathetically in an ensemble. Strength, power, dynamics and subtlety – all depending on the player’s style and intention. Such universality is based on C. Bechstein’s profound piano-making philosophy. Bechstein implements its well-founded knowledge at each step, nothing is left to chance. Join us in the secret world and art of C. Bechstein piano manufacturing.

1

The massive rim

The massive outer rim consists of strong beech combined with mahagony layers, which with their horizontal grain ensure maximum stability and optimum sound transmission. Horizontal and vertical solid beech layers complement the overall stability of the rim. These selected hard woods give the best possible support for the sound-board.

After gluing, an over one-half year special warehousing of the outer wall ensures for piano construction the best conditions for a maturation process while slowly and controlledly reducing tensions caused in production.

Later, in a further process of piano-making, a new tension is consciously established. Throughout the course of the whole construction process every uncontrolled development of forces, which would have a stiffening effect on the sounding board, is avoided. Bechstein piano construction is holistic and comprises really every detailed step.

1

The sounding board

The sound- board is supported in its vibrating performance by the inner rim and reactivated to optimize energy conservation and in turn a more vivid and longer-lasting tapering off of the sound. We very slowly acclimatize the very carefully selected high-quality sounding board wood (mountain spruce with very narrow growth rings) in climate chambers, so that after gluing the finished sound-board to the ribs a well-measured tension is established. The sound-board is slightly tapered to the edge in order to once again optimize the vibration capability and energy transfer. In Bechstein upright and/or grand piano construction the sounding board is a vibration membrane. The effort and precision afforded by Bechstein contributes to the fantastic sound quality.

1

The ribs

The ribs made of high quality tone wood serve on the one hand to distribute the vibration over the entire sound- board and also support of the sound-board against lateral pressure. The ribs are tapered to the ends and fit perfectly into the frame. Gluing the ribs to thesound- board causes a tension that is favorable to the board’s vibration characteristics. The ribs are measured individually for their elasticity. For the sounding board, Bechstein arranges matching ribs individually so that the whole board vibrates evenly and ribs can all work in unison. C. Bechstein’s traditional use of an (additional) main rib ensures a perfectly balanced distribution of string pressure and vibration of the strings over the entire sound-board. Our DVD of Bechstein piano construction illustrates this chapter very well.

1

The bridge

This system of ribs and sound-board is supported in turn by the bridge - that is the connecting point between the strings and sound-board. The oscillations are, thanks to the quality of the Bechstein's bridge construction method, undamped – and therefore there is no loss – as they are transferred to the sounding board, thus supporting the board’s vibration activity. C. Bechstein’s bridge consists of vertically laminated maple layers, some with mahogany strata. The double bridge - that is the contact area with the string - is made of solid white beech.

1

Sound-board bed - the frame

The sound- board, bonded to ribs and bridge, is allowed to develop over a generous maturation time and when it reaches the desired tension and curvature parameters is glued on its bed and the inner rim in final position. The sound-board bearing, the frame, is adjusted to a certain angle corresponding to the desired curvature in a pre-defined diagonal so that the sounding board’s arch is optimally supported. These complicated steps prevent vibration-resistant pressure on the board. Bechstein piano-building principles are truly comprehensive. Thus, superior quality is achieved.

1

The tension and durability

The C. Bechstein sounding board is somewhat tapered toward the edge. Recesses for the ribs, also called notches, are placed precisely with CNC technology, which guarantees an absolute minimal energy loss in the system. The board cannot expand uncontrollably; at the same time the durability of the tension is guaranteed. Tension in Bechstein upright and grand piano construction is the essential element.

1

The body

C. Bechstein defines the body as the unit consisting of outer and innerrims (also called back post or frame), embedded in which is the sounding board. In C. Bechstein piano construction, the body is under controlled tension in order to stimulate and support sounding board vibrations. The body, consisting of wall, support posts, barrier and key bed, is glued together before the sounding board is fixed into position. Thus, the sounding board is delimited and well secured. The extremely stable back post, the backbone of the instrument, is generally made from high-quality pine. Technically ideal dimensions, along with the important function of recording the tensile force of the strings, clearly supports the sound for the instrument’s various tonal registers. A prime example in C. Bechstein piano construction: The back post of the concert upright piano 8 is unique in design and adjusted in its dimensions to the back post of the concert grand piano.

1

Support posts

Wood for support posts (massive beams which can be seen under a grand piano) is specially selected. Only continuous woods are used. The advantage is expressed by a more dynamic sound and a refined tone development. Support posts are connected via dovetails with the back post and/or frame and further secured with studs. Support posts generally run together in one place on the barrier, where they are held in position and braced directly against the cast-iron plate by means of an iron connection. Thus, the energy cycle is completed within the sound body. Energy is a key concept in Bechstein upright and grand piano construction.

1

The resonator

In the treble area of the C. Bechstein grand piano models B, C and D, both the plate as well as the frame tension can be set with a metal resonator. This allows fine-tuning the region of high frequencies. Another special feature in Bechstein piano construction.

1

The cast-iron plate

Cast-iron plates are manufactured according to the most modern methods. The acoustic throughput time is controlled and measured, so that only plates with correspondingly high transit times are used in Bechstein upright and grand piano construction. C. Bechstein plates are cast in the sand casting process, not in a vacuum process. A special art, which enables high dimensional accuracy of the plate and an optimal profile of the cross sections. The plate has a significant influence on the tone. To complete the force and energy cycle, the plate is united with the support posts via a metal connection.
Components
Piano construction outer wall
Piano construction sounding board
Piano construction ribs
Piano construction bridge
Piano construction frame
Tension
Body
Piano construction support posts
Piano construction resonator
Piano construction cast-iron plate