Voicing is the fine process of shaping the tone that is produced when the hammers strike the strings.  Using a variety of techniques, including filing, poking with needles, and chemical treatment, a technician is able to alter the physical properties of the hammer felts to make notes sound brighter or darker, louder or softer.  Once the overall tone of a piano has been voiced per its owner’s desires, further voicing may be done to individual notes or sections of notes in order to achieve tonal balance and consistency across the entire instrument.

Because tuning and regulation also play significant roles in how a piano sounds, it is essential that a piano be finely tuned and its action regulated first before a proper voicing job can be done.