Piano actions vs. grand actions
Discover the difference
Renner actions: the quality promise
Renner products’ exceptional reputation stems from our consistent quality philosophy, which combines skill, expertise, and craftsmanship with technically sophisticated production methods. Renner’s customized machinery is state-of-the-art.
Our experienced staff and our precise technology are both essential to the superior quality of our products.
In addition to ongoing inspections during parts production and pre-assembly, Renner actions are carefully checked once more by specially selected and trained employees before shipment. This is the only way we can be sure that every piano action Renner produces will meet our stringent requirements on precision and reliability.
Natural materials in Renner actions
Besides the strings, two internal components have the most impact on the sound of an upright or a grand: the action and the hammer heads. Both categories of product are core competencies of Renner’s.
The Renner action is a complex system involving an incredible variety of individual parts and levers; together, they transport the player’s energy and musical expression out through the instrument’s resonating body. Each action is made up of around 8,800 components.
Natural materials like wood, leather, and high-quality felt are the heart and soul of this dynamic interplay. Any number of different woods may be used, including hornbeam, red beech, birch, mahogany, and kotibe. Hornbeam is preferred for joints due to its hardness, toughness, and light color. Weight, firmness, and thickness all play a role when it comes to felts. Renner quality symbolizes exceptional precision, stability, and reliability; with proper handling and care, our products can last for decades.
Renner produces two types of actions: upright actions and grand actions. The main difference between the two is that grand piano actions need to be horizontal and flat, whereas upright actions are just that: upright.
The hammer heads are the connecting link between the string and the action. Manufacturing hammer heads that will produce a clear, precise, voluminous tone – and allow piano-makers to adjust the instrument precisely to the artist’s wishes – requires many years of experience.
How intricate upright and grand actions differ
Comparing the design of a grand piano and an upright piano reveals many significant differences, and that includes their actions. Upright pianos have vertical actions: the upright hammers hit the strings from the front. The jack has to drop back under the butt of the hammer each time, which means that the player has to release the piano key completely before hitting it again.
Grand actions are structured differently: the hammers are horizontal, and when a key is pressed, the hammer hits the string from below. Here, too, the player needs to release the key somewhat so that the jack can move back into position, but since the jack glides back on a roller, the key does not need to lift completely. As soon as a grand piano key has returned about a third of the way to its original position, it is ready for the next strike. In short, the main difference between upright and grand pianos is that the positions of the hammers allow repetition of notes at different intervals.