Showing posts with label soundboard. Show all posts
Showing posts with label soundboard. Show all posts

Monday 22 February 2016

Fine Tuning

Tuning is not as easy as we'd like it to be. If the piano is to be brought up to pitch, then we can expect the piano to fight back. Pianos do not seem to like change! The construction of the piano, especially the soundboard and the strings, presents the tuner with a challenge. Raising the pitch creates pressures and counter pressures within the piano so there is little hope it will stand in tune for very long until the new stresses have had time to stabilise. 

If only piano strings stayed at the pitch we leave them! In theory, keeping a piano in perfect tune is a never ending job. Practically speaking we are left to do the best we can with any given piano. A tuner's work involves making compromises which are unique for every piano we tune. The more we know a specific piano, the more straightforward the task but we still have to make judgements on what the piano can give us. Some pianos, without serious rebuilding work will never sound good, but thankfully, most pianos allow a significant improvement in the tuning.

Because piano strings stretch, there is no point fussing too much when we first get to work raising the pitch of a piano. The middle section of the piano seems to fight the pitch raising more than the high treble and low bass, so it is worth, first time through, just tuning this section. Whatever method you use to fix the pitch, be sure to tune it well sharp at this stage.

Second time through, tune the middle section again taking more care with accuracy and maybe tuning a further octave up and down. Third time through is where we can fuss all we like to achieve our goal of the finely tuned piano! 


When I was learning to tune, the old tuners used to talk about 'setting the pin'. Never quite got a clear explanation of what this actually meant but it sounded rather mysterious and seemed to be understood only by the enlightened few. 


Of course, there is no mystery. Experience teaches keen learners how to manage a stubborn and unyielding piano. Pianos with very tight tuning pins are not easy to tune.
 Our aim is to get both the pin and the string to embrace the changes we make and to be happy about it! 

Happy pianos make happy pianists!

Tuner's Journal

©


Pianology

Monday 30 December 2013

How a Piano Works

The piano perfectly pairs mechanical movement with an infinite range of dynamics of sound. This pairing is made possible by the precision engineering of the piano action and keys, and the wonderful rich tones of vibrating strings. At the heart of the piano, the sound-board projects sound generated by the vibrating strings after they have been struck by the hammers of the action.

The hunt for the wood used for the soundboard begins in the forest. Experts look for trees with specific acoustic properties and are harvested only when a tree is ‘ready’. Foresters are specially trained to know the 'signs' that indicate when a tree is ready! For uninitiated observers, one tree will look pretty much the same as any other, but these guys know the appropriate time to fell the tree.

Manufacturers like to keep their methods to themselves. Some believe their designs, specifications and particular construction features give their pianos a unique sound and tone, and so are keen to protect their ideas from being copied.  

Glued to the sound-board is a wooden ‘bridge’. This is the all-important link between  the strings and the soundboard. Every string passes over the bridge and is kept firmly in position by locating 'bridge-pins'. These define one end of the ‘speaking-length’ of the string. The metal frame is fitted - attached around the edges of the soundboard, leaving the soundboard to vibrate freely. 

The frame provides the strength needed to withstand the sheer tension across the 7 and a quarter octaves of strings! Each string travels from the tuning-pin, through an agraffe or over what defines the beginning of the speaking length of the string, across the central part of the soundboard, to the 'bridge' (the end of the speaking length) and finally to the hitch-pin anchored in the metal frame. 

The soundboard is slightly convex in shape. This and the tension of the strings when tuned, produces a sensitive and highly charged unit at the core of the piano. 

The action and the keyboard - dealt with in another post here, are the mechanical link between the pianist and the sounds created by the vibrating strings. 

'How a piano works' is too complicated an issue to cover in a few paragraphs. This post is a general overview and I hope will help give the beginning of a clear understanding of the workings of a piano.

The Piano World

© Steve Burden  
Pianology