Piano Voicing Explained: Hammer Felt & Tone

A piano can be in tune yet sound harder, brighter or less enjoyable than it should be. Piano voicing addresses its tonal character through skilled adjustment of the hammer felt. The best description for piano voicing is that it is "acupuncture" for the piano hammers.
Understanding piano voicing helps you understand further the complexity involved in servicing pianos, but also to help understand what you hear, so that we can address and service pianos that have those harsh sounds.
What is piano voicing?
Each time you play, the hammers strike the strings. Over time, that area of the felt gets harder and can lead the piano to have a harsher, more metallic sound. Using specialised voicing tools, we carefully insert needles to help adjust the tone.
Music schools, especially those that teach beginners, often have an "unbalanced" tone, where the hammers in the middle have been used repeatedly, whilst the rest of the piano might have had comparatively lighter usage. Voicing can help restore the tone, so that it's warm and even, over the piano.
What tools are used for piano voicing
A voicing tool holds fine needles that a technician inserts precisely into the hammer felt. The tool allows for the length of the needle to be adjusted. Tools typically hold 3 needles at a time, however, the technician may use one at a time if required.

Piano hammer voicing: how long does it take?
Voicing a piano involves repeated listening and reassessment. Quite often we have to take the action out, do voicing, reinstall the action, play and listen. This is not something that can be quickly rushed, it is literally an art. Often a voicing session is between 1 to 2 hours, it can be longer, it all depends on your piano and what it needs.
Hammer reshaping and voicing
Often, piano hammers will develop grooves from where they have been hitting the strings. Voicing can help significantly with the tone, however, in some cases, removing a layer of felt from the hammers, which removes the grooves, can also make a large difference in the tone of the piano.
If the piano hammers have very deep grooves, often the procedure is to reshape the hammers, listen to the piano, and then start voicing.
Hammer reshaping is something that can be done in a home, however, often it is done in a workshop. Many times, I will personally prefer to take it to the workshop.
Sometimes people ask if voicing is part of piano tuning. Unfortunately, it's not. Voicing can easily be an additional 1-2 hour service alone. It is just not possible to bundle this into a tuning service.
Quite often, if your piano has not been tuned for a long time, we typically will not have time to do tuning and voicing in that initial appointment. This is something where we quote, and allow you to choose to have it done or not at ANOTHER day and time.

How often does a piano need voicing?
This is not something we can answer. Concert pianos, school and studio pianos will have a vastly different service schedule compared to someone with a piano at home. It's difficult to even give a baseline. Depending on usage, maybe once every 5-10 years for many home pianos. Hammer reshaping is even rarer. There are pianos that have had reshaping done at 10-20 year marks. There are pianos that are 40-80 years old that have never had it done!
There is genuinely no single answer that suits everyone.
Discuss your piano's tone with Jema Pianos
Jema Pianos provides piano servicing across Sydney and surrounding regions. Check our service area coverage and contact us to discuss your instrument's tone.