Symptoms
- Loud notes sound harsh, metallic or piercing
- The treble sounds tinny or glassy
- Hard to play quietly; soft notes jump out
- The sound is uneven, with some notes much brighter than others
Likely causes
Hardened hammers
Years of playing compress hammer felt and wear grooves into it, so the hammer strikes like a hard surface.
Hard, reflective room
Tile floors, bare walls, large windows and little furniture, typical of many apartments, amplify brightness.
Dry air
Low humidity hardens felts and tightens the soundboard, making the tone sharper.
Factory voicing
Some pianos leave the factory voiced bright, especially in smaller uprights and some newer models.
What you can safely check yourself
- 1Put a thick rug under and around the piano and add curtains or soft furnishings to the room.
- 2On an upright, move it 5 to 10 cm away from the wall and try angling it slightly.
- 3Keep the grand lid on the short stick or closed, or keep an upright's top lid shut.
- 4Measure humidity; if it's below about 40 percent, use a humidifier in the room.
- 5Note which notes are harshest so the technician can target them.
What not to do
- Don't stab or needle the hammers yourself; misplaced needling can ruin the tone permanently.
- Don't stuff towels or foam inside the piano; they can interfere with the action and dampers.
- Don't apply liquids or softeners to the hammer felt.
Quick fixes vs. call a pro
You can usually handle it
- Adding rugs and curtains
- Moving the piano off the wall
- Closing the lid
- Raising room humidity
Call a technician
- Needle voicing to soften hammers
- Filing grooved hammers
- Evening out bright and dull notes
- Installing a practice rail for quieter playing
What a technician will do
The technician voices the hammers: filing away hard, grooved felt and carefully needling the shoulders to make the felt more resilient, note by note, until the tone is even. A full voicing typically takes 1 to 3 hours and is often done after a tuning.
A piano holds about 18–20 tonnes of string tension. If a fix means opening the action, turning tuning pins or working near the strings, leave it to a technician.
In Israel
Israeli apartments with stone or tile floors and bare walls make pianos sound brighter, and air-conditioning dries the felt further. A rug and a voicing visit go a long way.