Piano Frequently Asked Questions
Q What do Overstrung and Straightstrung mean?
This is the type of stringing of the piano (usually applied to upright pianos - almost all grand pianos are overstrung). Overstrung pianos have their bass strings fitted diagonally from the top left of the piano (uprights) to the bottom right "over" the treble strings which go from top right to bottom left. All modern pianos are overstrung apart from a very few ultra small short compass examples.
Q All about strings
The sound of a piano is made by hammers hitting the strings. There are treble strings and bass strings.
The treble strings produce the highest notes. These are found at the right hand end of the piano. They are made of steel, the highest (thinnest) being guage 13 (0.775 mm) and the lowest (thickest) being around guage 22 (1.224 mm). They are together in threes, called a Trichord.
The bass strings produce the lowest notes. These are made of a steel core with copper wound onto it. When the strings are new they are very shiny like polished brass but they soon tarnish and become dull. When bass strings are very old the tone becomes deader. Sometimes the copper windings become clogged with dirt and the string just goes "donk" when struck!
There are over two hundred strings in most pianos. Each string is under a tension of up to 100 kilos. This means that the combined tension can be twenty tons in a concert grand! (Less in smaller pianos). This enormous force is kept in check by a very strong cast iron frame. Some old pianos have a wooden frame. This tends to move under the tension of the strings and the tuning is not stable in these.
The string tension is held up (and can be adjusted) by the tuning pins. The bottom end of the string goes over a 'hitch pin' and the top end of the string goes through a hole in the tuning pin and is wound round three or four times.
The piano is tuned by adjusting the tension on each string. This is done by winding the tuning pin tighter or looser.
Q Overdamping and Underdamping
The terms overdamped and underdamped apply to upright pianos only. Overdamping is where the dampers are above the hammers, near the top of the strings. This method of damping is not as effective as underdamping and the notes on an overdamped piano often tend to "ring on", this is where the note continues sounding even when the key has been released.
Underdamping is where the dampers are below the level of the hammers. The dampers are near the middle of the strings and so the damping is quite effective. This arrangement usually gives a nice clean note cut off once the key is released. See the picture gallery and look at the overstrung piano for an example of an underdamped action.
Q What is a "Birdcage" piano ?
This is an overdamped piano where the dampers are controlled by long wires which are connected to the back of the whippens. Thus the action looks like a birdcage.
Q How does a piano work?
A piano makes its sound by having tuned strings which are struck by hammers. When a key is depressed it activates a mechanism which throws the hammer at the appropriate string (or strings) and lifts the damper off to allow the string(s) to vibrate freely. The hammer strikes the string, bounces off and is caught by a checking device. The string(s) vibrate at a set pitch or frequency (different for each note). The strings are stretched tightly across "bridges" which are mounted on the "soundboard" to which the vibration is transferred. The sound is amplified by means of the soundboard which is a large flat piece of wood which effectively acts as a large loudspeaker.
When the key is released, the hammer falls back to its normal resting place and the damper is pressed back onto the string(s) to stop the vibration and thus the sound.
To see a diagram of an upright piano action click here.
Q How much does a piano weigh?
This depends on the make / type of piano but as a rough guide:
- Baby grand 4' 10" approximately 240 kilos
- Concert grand 9' approximately 490 kilos
- Small upright 112 cm approximately 180 kilos
- Large upright 131 cm approximately 215 kilos
Q What is concert pitch?
Concert pitch means merely that the note A above middle C is vibrating at exactly 440 times per second. Assuming that the piano is in tune with itself the whole piano is "At concert pitch". Sometimes in older pianos the frame will not take the strain of concert pitch (the higher the pitch, the more tension on the strings and frame). This means that it has to be tuned ""lower","flatter"or "down": this is where, with the piano in tune with itself A above middle C would be vibrating at less than 440 times per second. A common pitch for older pianos is "one semitone down" A=415 this means that if you strike the C key it will actually make the sound B, if you strike an F key it will make the sound E, etc. This means that you cannot use the piano to accompany other instruments unless you transpose all the piano music back up a semitone (which is a feat done only by rare musicians!). It also plays havoc with people with "Perfect Pitch", as their hands tell them one thing and their ears tell them another!
Q What about Grand Pianos?
Grand pianos come in many different makes, types and sizes. Grand pianos are considered to be better than upright pianos for two reasons.
The bass strings are longer (in a six foot or larger grand) than in an upright piano: the tone of a piano depends mainly on the length of string, the longer the better.
The "Roller" action found in modern grands gives a much better playing response than the best upright pianos vertical action.
ncert grand pianos are over nine feet long. The sound they produce is very powerful. Some models even have an extra eight keys in the bass so they have ninety six notes all together (compared to the usual eighty eight or eighty five.)
"Baby" grands go down to four foot in length, but in my experience these pianos are not a patch on a good upright. You can hear the difference in bass tone between a baby grand and a good upright in The Auditorium
Q What size is a baby grand, boudoir grand etc. ?
These terms are not really in use any more. Grands are now simply classified by size. However a rough equivalent is
- 5'8" or smaller Baby Grand
- 5'10" Boudoir Grand
- 6' (183 cm) Professional Grand
- 6'4" (193 cm) Drawing room Grand
- 6'8" - 6'10" (203 - 208 cm) Parlour, Artist, Salon or Music Room Grand
- 7'4" (224 cm) Half Concert or Semi Concert Grand
- 8'11" (272 cm) and larger Concert or Orchestral Concert Grand
Credit to Arthur A Reblitz's book "Piano Servicing, Tuning and Rebuilding" for the list.
Q How much is my piano worth?
This depends very much on the make of piano, the type of piano, its age, general condition, and so on. For a more detailed discussion of this subject please read the piano valuation page.
Q How often should my piano be tuned ?
This is a matter of personal taste. There are two extremes. Some people never have their pianos tuned because they say "I am tone deaf" (which is a myth). Pianos used for concerts are usually tuned before each concert, and often during the interval aswell!
Most domestic pianos require tuning every six months. This is not because they suddenly "go out of tune" at the six month mark but because they are gradually going out of tune all the time but six months is about the point at which most people notice they sound "off".
Q What is "Regulation ?"
Regulation or Action Regulation is essential to having a well responding piano. It is the setting up of each part of a piano action so that it does exactly what it should. This involves levelling the keys, fixing any broken action parts, and setting up each action part to its correct position / travel etc. A regulated piano has a uniformly graduated touch response and tone throughout its compass. See the Grand Piano Regulation Page for details on how it is done.
Q How does a piano work?
The sound of a piano is made by metal "strings" vibrating. This sound is amplified by the "soundboard". When a key is pressed the action of the piano transfers the momentum of the moving key to a felt hammer which is launched towards the strings for that particular note. The hammer strikes the strings and bounces off leaving the strings to vibrate. As the key is depressed the action lifts the damper away from the strings to allow the strings to vibrate. When the key is released the hammer falls back into place and the damper is returned to the strings to stop them vibrating.
Q What causes "Sticky Notes ?"
A sticky note is one where the note does not respond quite as it should e.g. it can be played once.
There are many causes of sticky notes!
Common symptons / causes and cures (upright pianos)
The note is played and the key stays down:
- The key itself is physically stuck down:
- The front of the key is fouling on the slip rail
- Slip rails is warped - shave some off or reposition it
- The front bushings are binding on the key pin
- The key pin is rusty - clean or replace
- The bushings need lubricating and / or easing
The key is free but the action has not returned:
- The note is played and the key returns but when struck again the note does not sound
- The hammer has not returned
- The tape has broken - replace
- The hammer flange is stiff - lubricate or repin
- The butt spring is broken - replace
- combination of the above
- The jack has not returned under the hammer butt
- The jack (spiral spring) is broken - replace
- The jack flange is stiff lubricate / repin
- The key capstan is adjusted too high - adjust down
- The whippen has not returned to its correct position
- The whippen flange requires lubriaction / repinning
- The front of the whippen is fouling (the frame sometimes) - shave some off (!)
- The damper spoon is corroded / caught against back of damper bottom (underdamper only) - replace damper box cloth and / or clean / replace spoon
If in doubt - consult your technician !
Q How should I clean my piano ?
Piano caseworks are finished in several different ways. Modern pianos often have a black polyester finish, or another synthetic finish. These are very durable but still need to be looked after with care. The best thing to do is simply use a wax impregnated duster.
Older pianos are often "French polished" which is a process which many layers of fine polish are built up and cut back to produce a very shiny finish. Some cheaper old pianos are brush polished and veneered or simply scumbled. Some rebuilt older pianos are spray polished with French polish or another synthetic finish such as a lacquer. These old pianos do not take kindly to any kind of spray on furniture polish which contains silicone (most do). A beeswax polish is the best thing to use as this will bring out the shine of the piano.
Q What is the piano's "Action" ?
This is the mechanism between the keys and the strings that controls how the piano responds to the key presses.
Sometimes the word ACTION is used to describe the way the piano responds.
Q Where to find Piano Serial Numbers
- A pianos serial number will usually be found stamped on its soundboard in figures about 2 cm high. Serial numbers are usually between four and seven digits long.
- A number stamped on the top of the side of an upright piano is probably a dealer's stock number.
- A number cast into the frame is almost certainly not a serial number.