Voicing and Piano Hammer Maintenance

Have you noticed that your piano sounds harsh, bright, excessively loud, or tonally inconsistent across different ranges of the keyboard? Despite routine tunings, perhaps you recall it sounding more pleasant or “warmer” years ago. If so, your piano may benefit from a standard maintenance practice called voicing (also called tone voicing or tone regulating).

Voicing is a broad term encompassing a variety of procedures where hammer felt is manipulated in order to improve the piano’s timbre, dynamic range, and tonal evenness.

The amount of voicing a piano may benefit from varies, and the degree of refinement possible depends on the piano’s overall design and condition.

Piano hammer with its molding and strike point labeled

What Is a Piano Hammer?

Modern pianos have 88 hammers (one for each note). Piano hammers are constructed of a wooden core called the hammer molding, with compressed layers of wool hammer felt attached around the molding. The result is a pear-like shape, with a small, rounded surface at the top of the hammer, termed the strike point.

The job of a hammer is to efficiently transfer energy from a piano key to the respective note’s piano strings, and to generate pleasing tonal qualities from the instrument in the process. The rounded nature and small surface area of the strike point are important ingredients for the effectiveness of this operation. Similar to how hitting a drum with different mallets produces different sounds from the same drum, the shape, size, and rigidity of the material on piano hammers can have a profound effect on the tone, sustain, and volume the piano produces.

Hammers and Their Wear Process

As the piano is played, each hammer’s strike point wears as it repeatedly contacts the strings, creating string grooves in the hammer felt. Some degree of string grooves is normal, but over time, string grooves can become so deep that the piano’s tone becomes compromised and uneven from note-to-note. The longer and deeper a hammer’s string grooves, the larger and flatter the hammer’s strike point becomes, compromising the hammer’s shape and negatively affecting the piano’s tone and dynamic range. As this gradual process occurs, the piano’s tone is often described as “loud,” “bright,” “less focused,” or “thuddy.”

Chart depicting piano hammers with no wear, moderate wear, considerable wear, and extreme wear

Correcting the hammers’ shape and “voice” through various voicing procedures described below will make the sound of the instrument more pleasant and even again. If your piano’s hammers are left unserviced, the tone will continue to deteriorate, and your hammers may require replacement sooner than if these services had been performed when suggested.

Voicing services are grouped into two categories:

Fine Voicing

The process of manipulating existing wool fibers in the piano hammers with needles or other tools in order to produce a more even and palatable tone from the piano. The degree and recommended frequency of fine voicing maintenance can vary significantly depending on piano use-type, frequency of use, and condition.

Fine voicing of piano hammer with needle

Hammer Filing (also called hammer reshaping)

In cases of considerable hammer wear, it may be necessary for the technician to file or “reshape” the hammer felt before fine voicing can be performed. Unlike fine voicing adjustments which manipulate existing wool fibers, hammer filing is the process of removing worn top layers of hammer felt, exposing a fresh layer of felt from underneath. Hammer filing is usually meant to restore a smaller strike point for flexibility in subsequent fine voicing.

In cases where hammers show extreme wear, with a flat strike point and deep, long string grooves, the technician may instead recommend replacement of the hammers.

Frequently Asked Questions

Which areas do you service?

We service the area denoted in green on the map below. This includes, but is not limited to: Ballantyne, Carmel, Dilworth, Matthews, Myers Park, Quail Hollow, South End, and SouthPark. Please contact us by phone at 704-593-6741 or by email at bradfantpianos@gmail.com to inquire about special accommodations.
How often do I need to have my piano tuned? Why does it go out of tune?

Generally, pianos should be tuned every 6 months or every year, even if they are not being played regularly. Pianos on the concert stage, in recording studios, or in schools may require more frequent tuning and attention. The piano's main structure and soundboard are both made of wood, which expand and contract with climate change and humidity variation. Fluctuations in the wood net an out of tune piano. It is especially important to tune new pianos several times during their first few years to ensure that the string tension and piano structure reach a stable equilibrium. For more information about tuning, please see here.
What is a "pitch raise?"

All modern pianos are designed to be tuned and sound their best at "standard pitch," where A4=440 Hz (A above middle C vibrates at 440 cycles per second). If a piano has not been tuned for an extended period of time (over ~12 months), has been through extreme climate fluctuations, or has been moved, the overall pitch of the piano may be significantly higher or lower than standard pitch. In this situation, the piano will require a pitch adjustment or "pitch raise" to bring the piano’s combined string tension back into a normal range before a standard fine tuning can be performed. A pitch raise and fine tuning are typically performed in the same service appointment, but in very extreme cases, where multiple pitch raises are necessary, a second appointment may be necessary. The need for a pitch raise cannot be determined without assessing the piano in person. For more information about pitch raises, please see here.
I'm moving. How can I move my piano safely and when should I have it tuned?

Moving your piano shouldn't be stressful and you most definitely should not attempt to move it yourself. Hire an insured piano mover, not just any mover! The piano is a fragile instrument and permanent damage can easily be done by an inexperienced mover. Please feel free to reach out if you would like a referral. It's generally recommended to wait about one month after your move to tune the piano, allowing it to acclimate to the new location. This will net a more stable tuning than had it been tuned immediately.
Do you repair digital pianos and keyboards?

We do not service or repair digital pianos/keyboards, and recommend contacting your instrument's manufacturer for a referral to a certified service center: Casio Kawai Korg Roland Yamaha
What is a RPT (Registered Piano Technician)?

The Piano Technicians Guild is a nonprofit organization that regulates the trade of piano technology. A RPT is a piano technician who has undergone and passed tuning, technical, and written exams according the the Piano Technicians Guild standards. The Registered Piano Technician certification is the only official guild certification for piano technicians in the United States. For more information about Registered Piano Technicians, please see here.
What type of payments do you accept?

Accepted forms of payment include: paper check, cash, Zelle, Venmo, Apple Pay, and all major credit and debit cards. For more information about payments, please see here.