FAQ What is action regulation?

A collection of FAQ's and informative articles on pianos

Moderators: Gill the Piano, FAQ's

Junior Poster
Junior Poster
Posts: 16
Joined: 09 Jun 2004, 09:36

FAQ What is action regulation?

Post by FAQ's » 09 Jun 2004, 19:27

Action regulation is the process by which the tuner maintains the moving parts to work as they are meant to.

What can be the signs of poor regulation?

Some guidance here may help. These items may also be useful in evaluating an instrument for purchase. A lot of what happens when the key is pressed can be picked up by feel. After all, it's the key that transfers your intentions into sound. The key must work efficiently, and accurately to do the job it was designed to do. Poor regulation can result in the note not working to its utmost efficiency. If you gently press the key, and feel a lot of "nothing happening", this could suggest that the key isn't set up properly.

In the trade, this is called "lost motion" which is one of the most common conditions one encounters. Of course a trained technician must carry out this kind of regulation. One thing that happens is that all of the regulation procedures are inter-related. Change one, and another one may be affected. When the key is pressed, the hammer is brought into contact with the string.

In a correctly maintained action, the hammer will release a split second before actually hitting the string. To understand this, think of a rocket being launched into orbit. The engines are turned off, and the rocket allowed to coast to its final position.

Same for the hammer. It is sent to the note in a sort of free fall. If this isn't happening, you may get a condition known as "blubbering." a sort of double-strike, when the hammer is brought repeatedly into contact with the string. Again, this condition must be treated by a trained, competent technician

Another attribute of piano regulation is something called "After Touch." This is harder to define, and describe. When the key is pressed down slowly, it brings the hammer up to the string. In an ideal situation, the hammer is released by the jack described above; I.E. the rocket has switched off. The key will continue to travel downwards a small portion. There is a slight kick, or bight transmitted back through the key as the jack is released, and the key bottoms out against the keybed where it rests. A small amount of after touch ensures that the key has done its job, rather than running out of steam before the hammer is allowed to make its way towards the string.

Blubbering can occur with not enough after touch. Your technician should be in a position to advise you regarding after touch. let off or set off. depending on which side of the Atlantic you are on. This is the regulation described in the earlier part of this reference. Remember the rocket? Well, setoff determines when the motor is shut down. If you notice abnormal behaviour in your piano, be sure to contact a qualified technician.

Robin Foster MABPT
UK Piano Page Copyright 1999 - 2004


Who is online

Users browsing this forum: No registered users and 1 guest