Symptoms
- The piano goes flat and out of tune soon after tuning
- New clicks, rattles or buzzing notes
- Loose, wobbly keys or a looser, noisier action
- Visible cracks in the soundboard or the case finish
- Tuning pins that feel loose to the technician
Likely causes
Soundboard shrinkage
As the soundboard dries it loses its crown (its slight upward arch), string tension drops and the pitch falls. Severe dryness can crack it.
Pinblock drying
The pinblock holds the tuning pins by friction. When the wood shrinks the pins grip less firmly and the tuning slips.
Loose glue joints and parts
Shrinking wood loosens ribs, bridges and action parts, which causes clicks, rattles and buzzing.
Heat sources nearby
Radiators, fireplaces, heaters, underfloor heating and direct sunlight dry one side of the piano faster than the other.
What you can safely check yourself
- 1Use a digital hygrometer near the piano; if it reads below 35%, take action.
- 2Run a room humidifier during the heating season or long AC periods, aiming for 40–50%.
- 3Keep the piano at least a meter from heaters, radiators and AC outlets, and out of direct sunlight.
- 4Close windows and shades during a hamsin and keep the lid closed.
- 5Listen for new clicks or buzzes after dry spells and note which notes they come from.
What not to do
- Don't put a bowl or jar of water inside the piano; it can spill and rust the strings or rot the wood.
- Don't point a humidifier straight at the piano; it should raise the room's humidity, not wet the instrument.
- Don't place the piano over underfloor heating or next to a fireplace.
Quick fixes vs. call a pro
You can usually handle it
- Measuring humidity and adding a room humidifier
- Moving the piano away from heat and AC vents
- Closing curtains during a hamsin
- Writing down which notes click or buzz
Call a technician
- A visible crack in the soundboard
- Tuning that slips within weeks
- Clicking or buzzing that doesn't go away
- Loose tuning pins found during tuning
What a technician will do
A technician tracks down buzzes and clicks, reglues or secures loose parts, checks the pins' torque and tunes the piano once humidity is stable. A visit usually takes 1–2 hours. For pianos in hard-to-control rooms, a humidity control system like Dampp-Chaser adds moisture in dry periods and removes it in humid ones automatically.
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
Jerusalem winters with central heating or radiators, long hours of air conditioning and hamsin days when humidity can drop to around 10–20% all dry pianos out quickly. In the Negev, Be'er Sheva and Eilat the air is dry most of the year, so a humidifier near the piano is often needed.