The art of piano tuning.
I’m a first generation piano tuner / technician with extensive ear training. Over the last 20 years, I’ve learned tuning is not just about understanding mathematics and pitch frequencies but more about the feeling each piano tells you where it wants to be tuned.
The process of tuning requires turning over 250 tuning pins & strings rotationally, clockwise & counter, until the desired pitch frequencies are achieved.
Every piano has roughly 15 -20 tons of pressure exerted on the frame; the cast iron plate & backposts or structural beams. This great amount of energy retained in the frame allows soundboard compression to exist so that volume is adequate. It’s the movement of the soundboard, primariliy through humidity changes, that causes most pianos to go out of tune.
Temperature, humidity, & pitch.
The best way to keep a piano in tune longer is to control humidity at 42% daily. Since Connecticut summers typically have higher humidity (brought in from the coastal air), you can see a direct correlation between high temperatures and high humidity. Yet, you’ll also notice in early January of 2023, the inside temperature is still high from home heating but the humidity dropped down from lack of air humidity.
Higher temperatures can hold more moisture before reaching their saturation point, so unless that dry air is supplemented with humidity through a humidifier, this affects the piano in multiple ways.
Dry air drops the string tension due to the reduction in the curvature (called the “crown”) of the soundboard, thus dropping the piano’s pitch, or lowering it below A440.
Glue joint becomes brittle in areas of the 5,000 internal action parts which allow the keys to perform their functions
Tone quality can change from warm and mellow to brittle and harsh from lack of moisture found in the highly compressed felt of each hammer
Art parts can shift, causing sticking keys or loose parts/screw joints
Tuning pins can weaken due to reduction in wood girth in the pinblock (multi-laminate hard maple wood which holds every tuning pin underneath or behind the cast-iron plate), causing permanent damage to the piano’s structural integrity.