In this seminar, Joachim Leonardy from the Jahn company addresses the complex topic of replacing hammer heads in grand and upright pianos. Selecting the appropriate hammer head is the first crucial step, where physical parameters such as mass, felt tension, and heartwood quality must be directly related to the acoustic characteristics of the respective instrument. Particular emphasis is placed on the analysis of geometric variables: The seminar examines in detail the effects of bore length and specific weight on the leverage of the action and thus on repetition and dynamics.

A clear distinction is made between the design requirements of upright and grand pianos, as the gravitational forces and the resulting impact energies necessitate different approaches to determining weight and bore size. The practical section discusses precise methods for the professional gluing of components and the strategic voicing of different instrument types. The aim of the seminar is to provide participants with technical know-how that will not only optimize the quality of the sound design, but also make it efficient in terms of saving time and effort.