What's Going On Inside A Piano?

Here are some basic terms you will see and hear when you start looking for a piano, either new or used:

Types of piano:

Upright (also called a vertical) – generally goes against a wall, but can be free-standing.
Sub-classified into:
o Traditional (has a leg and toe under the keyboard),
o Contemporary (keyboard is suspended in the air, always shorter than a Traditional piano for stability),
o Spinet (has two legs at the front but no toes – the legs go straight to the floor, shorter than a Traditional).
Grand – free standing piano supported at three points.  Can be any size from 4ft. to 9ft. plus.  Generally: Baby Grand – up to 5ft. 6ins. long, Boudoir or Drawing Room Grand – up to 7ft. 6ins., Semi-concert – 7ft. 6ins. or larger, Concert – 9ft. and over.
Square – the precursor of the modern pianos.  These are generally oblong in shape and are not considered up to modern standards for playing, although good if you want a piano of the period of the music you are playing.  I would not advise these if they are to be the only piano as they will not take heavy use.

Parts of the piano

Hammers – the pear-shaped wood and hard felt construction that strikes the strings making the sound.  The quality of the hammers makes a difference to the tone of a piano as does the amount of wear on them.  Heavily indented hammers can be reshaped if not too worn.

Dampers – wood and soft felt pads that stop the strings from vibrating – can be above (overdamped) or below (underdamped) the hammers on an upright piano and are generally on top of the strings on a grand.
Old dampers are less efficient as the felt is compressed by years of usage making the piano ‘ring on’ (the note does not die away when the dampers fall back).  Poorly adjusted dampers will give the same effect.

Strings – modern pianos have three strings (trichord) per note in the treble (high notes), two in the high bass (bichord) and single strings in the bass and these strings are crossed over each other (making an X shape when you look at them) – a configuration called ‘overstrung’.  Very old pianos were strung bichord throughout and often the strings were side by side (straight-strung).
Tuning is important – an out-of-tune piano may sound charmingly honky-tonk at first but will eventually become a source of irritation.

Wrest Plank and Tuning Pins – the wrest plank is a multilayered slab of wood into which the tuning pins (holding one end of the strings) are tightly fixed.  Over the years, the strain of the strings pulling on the pins can make the pins loose and they will not hold firm in the plank. The plank can also split, loosening its grip on the pins, although most times this will not be obvious to the casual glance. In either case, the piano will not hold a tuning and the remedy is replacement of the pins with larger ones in the first instance and replacement of the plank in the second – an enterprise which is usually an uneconomic prospect for all but the best quality pianos as this involves completely stripping the piano down and would only be undertaken as part of a full restoration.
Many used pianos are sold privately and in almost all cases the seller will say something along the lines of 'it hasn't been tuned recently, but it will need tuning after it's moved anyway'. While there is some truth in this it isn't helpful to you when you're trying to assess whether the piano you're looking at is capable of holding a tuning.

Frame – also called the plate or harp, this is the cast slab of metal that holds the other end of the strings.  Very occasionally a frame cracks, but this is unusual.  There are still some pianos with wooden frames but these are to be avoided unless you know the piano can be tuned to an acceptable pitch.

Soundboard – the thin board at the back of an upright and underneath a grand piano.  This is the amplifier of the piano and ideally should be made from planked solid spruce.  This is expensive and there are pianos that have laminated or plywood soundboards to reduce costs.  Yamaha, at the time of writing, make at least one upright piano with a laminated soundboard.  They admit it is a compromise between sound quality and price.  Old soundboards may sometimes develop small splits but, unless these ‘buzz’, splits should not be considered a problem in older pianos. New pianos should not show any signs of splits in the soundboard.

Action – all the bits from the keyboard to the hammers that mean that when you press a key down the piano makes a sound.  A piano action is extremely complex - there are over 8000 moving parts in a piano -  and unless all the springs, felts, bushings, looping cords, checks, jacks etc. are in good condition the piano will feel uneven to play, may have ‘sticking’ notes or poor repetition and will discourage the pianist.

In my next post I'll be looking at the difference between reconditioned, refurbished and restored used pianos and what you can expect from each of them.