Đàn Piano Steinway & Sons S-155

Instrument

Rim
Made entirely from hard rock maple; 12 laminations; continuous bent, both inner & outer form one single rim; unequaled strength & stability. Thickness: 2 1/8" (5.40 cm)

Braces
3 solid spruce with a volume of 1, 224 cu. in. (20, 058cm3); Spruce provides tensile strength with less weight. Maple dowels fasten braces to rim & crossblock producing a single homogenous foundation upon which is built the tonal component. Note: Treble bell is not required in smaller grands of lesser tensions.

Pinblock
Hexagrip patented design; 7 laminations of quartered hardrock maple stock. Grain symmetrically distributed at successive angles of 45° or 90° employing grain direction uniformly around the circumference of the tuning pin to provide the ultimate in pin grippage. As a result of this exclusive design, the tuning pin has smoother movement under torque, a more uniform retaining action for solid setting, and a piano which will hold its tuning longer.

Soundboard
Created like the soundboard of violins to give a free and even response throughout the entire scale, it is so constructed as to be 8 mm thick in the center and tapered to 5 mm as it approaches the rim and outer case before being DOUBLE CROWNED. This design permits complete freedom of movement, while acting as a homogenous unit to displace a greater amount of air, thereby creating a richer and more lasting tonal response. Close-grained, quarter-sawn Sitka spruce, a wood having unusual stability and vibrance under stress and vibration, is used exclusively for the soundboard.

Ribs
Made from durable, resinous sugar pine to assure strong and constant support of string down-bearing on the soundboard. Rib ends are hand-fitted into their mounting surfaces virtually locking in the important soundboard crown.

Bridges
Treble: Hard rock maple vertical laminations capped with solid hard rock maple; planed to prescribed height, graphite coated, drilled, and notched by hand for precise individual string bearing. Design defies splitting. Bass: Solid rock maple mounted to cantilevered and splined base. Maple doweled, glued, and screwed to soundboard.

Scale
Overstrung; combination agraffe; Front AND rear duplex. Tension: 32, 332 lbs. (14, 550 kg)

Plate
Sturdy gray iron; filled, hand-milled, and sealed; bronzed and lacquered.

Tuning Pins
Pins Premium blued steel with rust-resistant, nickeled heads.

Strings
TREBLE: Twelve whole & one-half sizes from high-tensile Swedish steel. BASS: Swedish steel core wire wound with pure copper. Longest, agraffe/bridge: 45 1/2" (116 cm)

Hammers
16.5-pound (7.48 kg) premium wool top felt over premium wool under felt; treated to resist insects and moisture. Compression-wired to retain permanent shape. Hard birch moldings. Shanks from select resilient maple.

Dampers
Horizontal-cut premium wool for effective dampening. Maple heads for endurance.

Action
White, quarter-sawn maple parts are bushed with specially treated wool action cloth for freedom from friction. Parts are anchored in hard maple dowels housed in inflexible seamless brass tubing to assure precise & stable regulation. Exclusive single, combination phosphor bronze repetition and fly spring provides constant crisp touch response. Specially designed to respond 14% faster fortissimo & 6% faster pianissimo by using an exclusive combination of half-round balance rail bearings and strategically placed key leads.

Keys
Bavarian spruce, individually weighed-off. Chip-proof, stain-resistant coverings for naturals; slip-proof, delicately abraded ebonized sharps. Tough, durable Linden wood buttons reinforce keys over balance rail permitting maximum tonal power with every strike. Longest: 19" (48.3 cm)

Keybed
Made from planks of stable, quarter-sawn spruce. Horizontal planks are freely mortised together, while their ends are permanently mortised into vertical planks, presenting a vented system for humidity escapement while allowing for necessary expansion and contraction. Front center is crowned contrasting the reverse-crowned action frame for snug fit. This design intensifies key movement and prevents "slapping" during heavy playing. Large maple dowel ends provide a solid mount for adjustable brass touch-regulating screws. Thickness: 1-3/4" (4.45 cm)

Pedals
Heavy, solid brass. Soft, sustaining, and full sostenuto.