Within certain limits, the dynamic range, tonal colour and other aspects of the pianos “voice” can be adjusted according to your personal taste and in relationship to the acoustic situation. With constant playing every piano’s tone will change, mainly because hammer felts will develop compactness by repeatedly hitting the steel strings. High humidity on the contrary may cause a softer tone, because the hammer felt will collect the air’s humidity. These changes will not affect each hammer to the same extent, thereby causing the piano’s timbre to become uneven. Voicing is the art of adjusting the piano’s tone; the work is done on the hammer felts, which are being treated with special tools. This service demands special skills and should be performed only by a very qualified professional piano technician.