Types of piano action and purchasing second hand pianos

The picture above is of an overdamper piano action (sometimes known as ‘birdcages’ because of the way hammers are obscured by the wires of the action) and these account for roughly 20% of the pianos I encounter. A customer in Sheffield asked me about the difference between the types of piano action so they know what to look for when buying a new piano. 

There are two main types of piano action on the market today, overdamped and underdamped. Overdamped pianos have felts nearer to the top of the string which makes tuning the piano much more tricky. But from the point of view of a piano player rather than a piano tuner, it is simply more efficient to have the felt nearer to the middle of the string as they deaden the note more effectively. The notes on an overdamped piano sustain and ring on for longer which isn’t always a desirable effect. If you have an overdamped piano the chances are that is at least 75 years old as production of overdampers ceased in the 1930s.

An Underdamped Piano Action

An underdamped piano will usually be much newer than an overdamped piano which is definitely a bonus when it comes to pianos. That said, it’s all subjective and some people are attached to an overdamped piano that has been passed down from an older generation and refuse to part with it. Some people like the character that an old piano has and they can often look nice in your living room, but it’s just not advisable to pay for a second hand overdamped piano when you can easily find a better piano for an affordable price. If you have been given an overdamped piano and aren’t willing to part with it then the good news is that it can always be made to sound a bit better than it did before, but if it hasn’t been maintained very well then keeping it pefectly tune will be impossible (I’ve tried tuning a 100 year old piano before for a Sheffield customer and it went out of tune as I was tuning it).


I will write more about the different types of piano action in another post, as there is a lot more to consider than the difference between overdamped vs underdamped pianos….


– Richard, Piano Tuner Sheffield