Archive for January, 2013

The History of Piano String Tension

Blah! The title of this sounds to most as exciting as watching paint dry.  Operative words being “to most”… to me however this is one of the more interesting charts i’ve seen in a long time.  Back in 2005, published by Europiano, Juan Más Cabré wrote this article showing the differing string tensions over the last few hundred years. Everything i know about string tension i learned as a child with a bread pan and rubberbands. Hahaaa… i used to make musical instruments when i was a kid. What fascinated me though was the thickness of the rubber band and the sound that would happen at a certain pitch. This is exactly what’s going on in pianos. The graph shows the earliest of pianos from Cristofori (in 1726). That string tension is little more than that of a harpsichord. It became evident that a stronger frame would be neccessary to implement higher tension. With higher tension comes more singing tone. Next on the list is Silbermann who asked Bach for some input. Silbermann contributed the damper device (similar to a damper pedal) to the piano. Shortly thereafter in the Classical era (Beethoven’s time) more and more iron was added to the wooden frame so as to boost the string tension – again with more singing, sustaining sound and also more resonance and power. Enter the famed Steinway and Bosendorfer. Interesting to note is that “more is not always better”. There have been pianos that have had higher string tensions (as in Ibach) but manufacturers decide what sound is pleasing. This is part of the backbone of ‘scale’ – the trade secrets of piano makers. Length of string, thickness of wire and tension of string all add to the sound. To get a mini idea of this, play around with a bread pan. It really is a fascinating exercise in string tension. And after that… just make some fresh bread. Nothing beats music and food together :)

Another funny…

Two old guys come into the church hall where i’m tuning up some old and forgotten piano.  The one says to me “You can’t honestly like doing that all day?”  The other says “How do you stand that incessant banging??”

I simply replied, “I dunno… i guess i just

(wait for it)

TUNE it out”

We had a good laugh.

How Often Should Pianos Be Tuned?

There hardly is a day that goes by when people don’t ask “How often should i tune my piano?”  To understand this question, there are a few variables you need to be aware of.  Firstly, there are roughly 18 tonnes of string tension pulling on most pianos at any given time.  To say to me “We hardly ever play it” in some ways is irrelevant because the strings are still under tension regardless of whether your hand touches the keys.  That said, pianos that get play a LOT will go out slightly if the tuning pins have not been properly set when tuning and i have noticed that more frequently used teaching pianos require more attention.  Second, humidity change plays a large part in tuning stability.  The strings are not just stretched from one end to the other.  They go over a bridge (much like you would see on a guitar).  That bridge is attached to the soundboard and depending on seasonal changes in humidity, the piano will fluctuate in pitch as the wood expands and contracts.

Now then, once you understand all of that, my usual response when asked how often pianos should be tuned is this: Depends how particular you are in having it in tune.  Recording studios and concert halls have it tuned every time it’s used.  Some churches even locally have it tuned once a month to quarterly depending on budget.  Most teaching studios tune twice a year.  Most families tunes yearly.

“But my piano doesn’t go out of tune that often”… hahaaaa.  I’ve encountered VERY few pianos in my lifetime and i’ve played over a thousand that rarely go out of tune.  My guess is that the piano is just gently creeping out of tune in such small increments that you don’t realise it’s gone out a few degrees.  My rule of thumb is that most people can’t hear when a piano is out of tune up to 6 degrees!  A degree in tuning is called a cent.  A semi-tone is 50 cents.  Full tone 100.  When pianos are out by about 3 or 4 degrees, the piano has still dropped in pitch but may not have been noticed.  Well… wait another year and then it’s out another 3 or 4.  Sooner than you know it, the piano has sunken 12-15 degrees over 3 or 4 years and instead of simply correcting a few degrees, you’re pulling strings.  My advice? Whether you hear it or not, do yourself a favor and keep it in regular maintenance.  And besides, like freshly squeezed orange juice, nothing beats a freshly tuned piano.

Go to Top