Sunday 18 November 2018

A history of pitch standards in piano tuning

In a previous post I explained that "standard" or "concert" pitch means that the note A above middle C has a frequency of 440Hz (cycles per second), and that this was settled upon at a conference in 1939. However, someone recently asked me what pitch would originally have been used for a late nineteenth-century Broadwood grand piano. This is a difficult question to answer, since prior to A=440Hz, there was no single universally agreed standard. So I thought it might be interesting to have a look at the different pitches pianos were tuned to in the past, and how the current standard came about.

The situation can be summed up fairly well by looking at this set of tuning forks, which would date from around a hundred years ago. These are "C" forks which probably would have been used by a piano tuner in the early part of the twentieth century, and there are four different pitches as inscribed on the side of the prongs:

C 517.3 Continental
C 522 New Philharmonic
C 528 Medium
C 540 Old Philharmonic

An set of tuning forks (left) used about a hundred years ago. Two modern forks (C523.3 and A440) are on the right.

It seems to have been a feature of the British piano trade that people were traditionally (and commonly still are) taught to tune using middle C as the reference note (although the forks are actually an octave above this). If we recalculate these frequencies (assuming equal temperament) to values for the note A, which is the generally accepted standard for orchestral tuning, we get A=435Hz, A=439Hz, A=444Hz and A=454Hz (none of these corresponding to modern standard pitch, though "New Philharmonic" is close). From the fact that tuners were carrying these sets of forks around, it would seem likely that these may all have been used at various times depending on the requirements of the customer, and no doubt all of this caused considerable confusion!

To work out the origin of all these pitch standards, we should transport ourselves back into the late eighteenth century, when pianos were becoming widely produced and available for the first time. It should be noted that during this period, there was no standardization of pitch. At the time, absolute pitch could only be measured with limited accuracy - for example, the Italian mathematician, Vittorio Francesco Stancari (1678-1709) had experimented with a toothed wheel as a tone generator. It should also be mentioned in passing that the French mathematician Joseph Sauveur (1653-1716), who worked extensively on acoustic theory, was an early advocate of pitch standardization and in 1713 proposed that middle C should be 256Hz (known as "scientific" or "philosphical" pitch as each "C" has a frequency which is a power of 2), which would correspond in an equally tempered tuning to A=430.54Hz. Apparently, Sauveur's efforts were not particularly welcomed by musicians in his own time, and this pitch has never been widely used as a musical standard (though Italian musicians briefly adopted something similar in 1881, actually A=432Hz, before agreeing to the A=435Hz at the Vienna conference of 1885); however, medical tuning forks, employed for the measurement of hearing, are quite commonly found at this frequency.

The tuning fork had been invented in 1711 by John Shore (1662-1752), a prominent British musician, so it would have been possible to have a convenient portable reference of relative pitch from this time onwards, and it may have had at least some effect in reducing the enormous range of standards in use. A fork made by Shore, which he gave to the composer Handel, still exists today and has a frequency of A=422.5Hz. A fork belonging to the instrument maker Johann Andreas Stein in the 1780s, whose pianos were played by Mozart, comes in at a similar value of A=422Hz, so this is likely a tuning that would have been familiar to musicians of this period. However, there was no consistency - some church organs built during the period have A as low as 390Hz, and some chamber instruments (according to contemporary measurements) were as low as around 410Hz. At the other end of the scale, some organs in Germany that were played by Bach have A as high as 480Hz - a difference in pitch of nearly a major third!

Nonetheless, it seems quite likely that, allowing for significant variations, the pitch of Shore's tuning fork was fairly similar to what might have been used in the early days of piano tuning. Several tuning forks survive from the early nineteenth century - for example a tuning fork used by John Broadwood & Sons, piano makers, from 1800 is equivalent to approximately A=423Hz (it's actually a C-fork) and some from the 1820s give A=428Hz. However, in the first half of the nineteenth century, a trend became very apparent: pitch used by instrumental performers, especially orchestras, was getting higher and higher, a phenomenon often described as "pitch inflation". It is possible that one factor in this trend was a set of musical instruments presented by Tsar Alexander of Russia to the Austrian Army on the occasion of the Congress of Vienna in 1814, tuned to a higher pitch than was normal for the time. The use of higher pitches and wind instruments or increased tension on strings gives a more "brilliant" sound with more overtones, and in the course of the quest for this, pitch inflation continued unabated. (It is true that pianos too can sometimes have a brighter tone when the pitch is raised, but of course they are not normally tuned by the performer, but rather by someone who does not want to break any strings!)

Pitch inflation and tuning in the nineteenth century

In any case, the early nineteenth century was the heyday of the orchestra and by mid-century pitch inflation was almost out of control, with some orchestras (such as the London Philharmonic) going higher than A=450Hz - a full semitone above what it was in Mozart's time. Needless to say, this development was received with much chagrin by singers, who were straining their vocal chords trying to reach the ever-higher notes. The situation became so bad that in 1859, the French government decided to act and declared that by law A=435Hz was in future to be the standard for musical performances. This standard was known as the "Diapason Normal" (diapason is French for a tuning fork), but in English-speaking countries was normally referred to as French Pitch, Continental Pitch (as in our set of tuning forks), or International Pitch (this last term should be used today with caution as it may be taken to mean International Concert Pitch, or A440). This pitch was adopted by several other countries (it was adopted at an international conference in Vienna in 1885) and remained an important standard until the adoption of A440 in 1939; however it was by no means universally accepted, possibly not even in France, and certainly not elsewhere, e.g. the Vienna opera is recorded as using A=447Hz in the 1870s. In particular, the British held out at the "Philharmonic Pitch" of approximately A=452Hz (it is actually a bit of a moveable feast) for orchestral performances until almost the end of the nineteenth century.

Another development around this time is also worthy of mention: Johann Scheibler, a German silk manufacturer who was a self-taught acoustician, invented a "tonometer", a set of 56 carefully calibrated tuning forks, arranged by carefully counting "beats" between adjacent pairs and measuring them using a pendulum or metronome. This enabled a more accurate measurement of absolute pitch than had previously been the case. At a conference of German scientists attended by Scheibler in 1834, A=440Hz was proposed as a standard pitch, although it was not widely adopted - however it may have been used in some parts of Germany (e.g. the Dresden Opera in 1862), and by the Streicher piano company. Incidentally, around the same time as Scheibler, a Frenchman called Felix Savart was experimenting with toothed wheels as more accurate tone generators.

However, this does not really answer our question of what piano tuners were doing in the latter part of the nineteenth century. There is some evidence from records and tuning forks of common practice in the UK. The Broadwood company was using three different pitches which seem to have stayed very roughly the same - a "low" pitch, starting at around A=433Hz but which eventually seems to have settled down to the French standard of A=435Hz, a "medium" pitch of around 446Hz, which eventually moved to around A=444Hz, and a "high" pitch equivalent to the Philharmonic Pitch (later referred to as "Old Philharmonic") which varied between around A=452Hz and A=455Hz.

Around the 1860s, Broadwood tuners were issued with sets of three "C" forks, marked "Vocal", "Medium", and "Philharmonic", corresponding to tunings of A=435Hz, A=445Hz and A=452Hz respectively. The low pitch was presumably used for singing, the medium pitch probably for standard domestic tunings and the high pitch perhaps for concerts or playing with other instruments. These three pitches are the ancestors of three of the four tuning forks in our early twentieth century set: the Continental (A435), Medium (A444) and Old Philharmonic (A454). 

The final one derives from 1896 - under Sir Henry Wood, when the famous Promenade Concerts were first instigated, the very high orchestral pitch was abandoned, supposedly in favour of A435. However, this was incorrectly assumed to apply to a temperature of 15⁰C (59⁰F) - in fact it was an absolute standard. In a concert hall at 20⁰C (68⁰F) the pitch of brass instruments tuned to A435 at 15⁰C would rise to approximately A=439Hz, so this was adopted as the new standard, and became known as the "New Philharmonic" pitch, with the previous, higher, pitch now referred to as "Old Philharmonic". This was still not an end to the matter, as the British Army continued to hang on to the old higher pitch for its military bands until the 1920s. The cost of replacement of the older instruments tuned to the higher pitch may have been a significant factor in this.

In his book "A Treatise on the Art of Pianoforte Construction" of 1916, Samuel Wolfenden, chief designer for the well-known firm of George Rogers and Sons, describes the same four pitch standards, the only difference being that the "medium" pitch is given as C=530Hz (A=445.7Hz), which he describes as the old Society of Arts pitch (from the Royal Society for the Encouragement of Arts, Manufactures and Commerce), and also notes that both the Medium and Old Philharmonic pitches varied slightly because of "slight concessions to the conditions under which pianofortes are used in combination with wind instruments at high temperatures". He describes the Continental pitch of A435 as "general throughout Europe" and said that there had been many years of contention among musicians due to the use of the high pitch [Old Philharmonic] which was obnoxious to vocalists; he comments that it is "retained because used by military bands...because of the great expense of new instruments." He also mentions in passing that "quite recently an influential committee of musicians and manufacturers in America has established a pitch founded upon A=440 v.s. [vibrations per second]."

In an article to the "Organist and Choirmaster" magazine of July 1899, the piano manufacturers John Broadwood & Sons put themselves at the forefront of the drive to move to the then newly established standard of A439, commenting that: "So far, pianoforte makers have held aloof and made no effort to secure uniformity in regard to the pitch at which their productions are tuned. Some favour one pitch and some another. The consequence is that if a visit be made to any of the large emporiums in provincial towns where pianos are sold, the visitor is hampered in his choice by seldom finding all pianos in the same show-room tuned to a uniform pitch." The letter continued: "In regard to concert grands, the want of uniformity in regard to pitch is serious, and necessitates makers keeping a double number of instruments." They had written to other manufacturers about this matter, which seems to have led to the use of the "New Philharmonic" pitch as at least an informal standard for British piano tuners around this time.

A selection of three forks used in the middle of the twentieth century - A439 (marked New Philharmonic) on the left, A440 (marked British Standard) in the middle and A452.5 on the right.
Another set of forks from a piano tuner's kit around the middle of the twentieth century contains three "C" forks. The one on the left, labelled "New Philharmonic" is equivalent to A=439Hz as one would expect, the middle one is an A=440Hz fork, and the one on the right is a slightly different version of an Old Philharmonic fork, A=452.5Hz. In her 1933 book "The Piano-forte, its history traced to the Great Exhibition of 1851", Rosamond Harding describes the use of the New Philharmonic A439 pitch as "almost as universal in this country as on upon the continent, though pianos are occasionally tuned to the old Philharmonic pitch, a' 454 (c'' 540)." (The idea that the New Philharmonic and Diapason Normal were in some sense the same seems to have persisted for a long while).

The road to A440

So having meandered through the many twists and turns of the various old tuning standards, it seems appropriate to come to the question of how A440 came about. It appears that in the United States, there was relatively little pitch standardization with A continuing to creep upwards, getting to somewhere between A=455Hz and A=460Hz (Steinway were apparently using A=457Hz in 1890). An early advocate of A440 as a standard was J C Deagan, proprietor of a company producing percussion instruments, notably including tuning forks. He described it as the "higher German pitch" (in contrast to A435), but there also seems to have been an argument along the same lines as the New Philharmonic Pitch - that when concert halls were heated (in this case to 72⁰F from the 59⁰F on which the French standard was supposedly based), the pitch of wind instruments rises to A=440Hz. The American Federation of Musicians adopted this in 1910, and it seems to have gradually gained acceptance, being generally used by the US recording industry after 1925 and ratified by the American Standards Association in 1936.

In May 1939, a meeting at Broadcasting House, London (facilitated by the British Standards Institute) was held, attended by delegates from France, the Netherlands, Germany and Italy, with representations from Switzerland and the United States sent by telegram. It was this conference that eventually agreed on A=440Hz as the new standard, although some British representatives were still in favour of A=439Hz. It seems that the British electrical engineer James Swinburne (1858-1958), a keen musician, may have played a role in advocating A440 as it is easier to subdivide mathematically. Apparently piezo-electronic generators of the time (as used by the BBC) worked on the basis of a tone which was divided or multiplied by particular numbers and as 439 is a prime number, 440 was easier to work with in this respect. To what extent this really was a factor in the decision I don't really know, but in the end 440Hz was agreed upon, practically the last thing anyone across Europe reached consensus about before the outbreak of the Second World War. In 1955 the International Organization for Standardization confirmed this standard as ISO 16, and reaffirmed it in 1975.

Well, with agreement reached, that should bring us to the end of our discussion... but in fact, it does not. Notwithstanding the fact that A440 is the only agreed international standard for tuning musical instruments, today the majority of orchestras in the world do not tune to this frequency (jazz musicians generally do, however). In fact, there is a website here (should you ever need to know) giving the tunings used by various orchestras in countries around the globe.

Firstly, it would be worth saying a little about the lower pitch standards in use today. For early music, both A=430Hz and A=415Hz (sometimes called Baroque pitch) are often used. These do not reflect the exact tunings actually used in the Baroque period (as there were no standard tunings), but rather are convenient compromises. Both are probably closer to the actual (albeit inconsistent) tunings that were used, but an additional consideration is that it is somewhat safer to tune historic instruments (at least in the case of harpsichords or early pianos) below A440. The 415Hz tuning is also highly convenient as it is exactly a semitone below modern standard pitch and therefore can be played with modern or standardly tuned instruments if the parts are transposed by a semitone.

Leaving the question of early music aside, however, it is clear that many orchestras tune to 441, 442, 443 or 444Hz, in search of that same brilliance of sound as their nineteenth-century predecessors. To understand this, we should consider the old French pitch of 1859 - the important thing is that, although many musicians ignored it, up until 1939 it had the important effect of putting a brake on pitch inflation. In fact, the whole thing is a bit like inviting people to turn up to a party at 7.30 when you actually want them to come at 8, since if you asked them to come at 8 they would actually come at 8.30. In the same way, whatever pitch standard is set, some people will try to push the envelope, but normally only so far.

Sunday 2 September 2018

Piano pedals (3) - the sostenuto pedal and the rest!

"There are three pedals on these grand pianos. Don't let that confuse you - the pedal in the middle is there to separate the other two pedals - which will be wonderful news for people with three feet." - Victor Borge
 
Having covered the sustain pedal and the various soft pedals in previous articles, a few pedal functions still remain to be covered. The most commonly found of these are the sostenuto pedal and the bass damper pedal, but there are a few others as well, many of which could fall into the category of the "weird and wonderful". The middle pedal on a grand piano is normally the sostenuto. The middle pedal on an upright is often a celeste pedal (most modern uprights, and the small number of older German uprights that have a third pedal), occasionally a sostenuto pedal (a few, mostly modern, uprights), sometimes a bass damper pedal (older American uprights) and sometimes, as I mentioned in the last article, a dummy pedal.

The sostenuto pedal

The sostenuto is a selective sustain pedal - when it is engaged it will hold off the dampers on any notes that are already pressed down at that moment, but not the others. On a grand piano, the typical mechanism for this is seen in the diagram below:
The sostenuto rail is a rotating metal strip which is mounted at the back of the action in roughly the position shown in blue. The pedal rotates the sostenuto rail as shown by the green arrow, when it catches the red protrusion on the front of the damper knuckle on any notes already pressed. The damper is actually forced upwards a little by the rail, so the other dampers can continue to function normally.
The sostenuto was first developed by French piano makers Boisselot & Fils and first displayed at the French Industrial Exposition of 1844. However, the innovation was not taken up by other European makers; it was eventually adapted by Albert Steinway and patented in the US in 1874. It was subsequently fitted to Steinways and other American-made pianos, but was accepted by European makers as a matter of course only relatively recently. Interestingly, the Steinway company themselves reflected this difference - older Steinways made at the New York factory generally have the sostenuto pedal, older Steinways made in Hamburg don't. This pedal is found on nearly all modern grands but only on a few upright models.

As sostenuto pedals are quite rare in the UK, many people will never have had the opportunity to play one, so here's pianist Frederick Hodges enthusing about the advantages:

Bass damper lift pedal (uprights only)

This is just like the sustain pedal, and works in much the same way, but instead of lifting off all the dampers, raises those in the bass section of the piano only. This is sometimes found on American uprights, but is extremely rare on pianos that are found in the UK, since (as already mentioned), most older European-made pianos only have two pedals, and the mainly modern instruments that do have three normally have a celeste as the middle pedal. For the same reason, dummy middle pedals that don't do anything at all are very rare on European-made pianos.

The bass damper lift is sometimes referred to as a "faux sostenuto" since it will allow (for example) the sound of a bass chord to be sustained independently. 

Four or more?

The pedals already described cover almost all of those found on modern instruments. A very small number of modern grand pianos have a fourth pedal which is a half-blow pedal (in the same manner as an upright) - this is found on certain models by Italian manufacturers Fazioli and Australian makers Stuart & Sons (and possibly others). Also, a few models (including some by Feurich) have a fourth pedal, located to the right of the sustain pedal, which is called the "harmonic pedal" - this seems to have the effect of raising the dampers to allow resonance of the other strings, but reapplying the damper to the note that has just been played.

...and the just plain kitsch...

On some early pianos (pre-1850), a large variety of different pedal functions can be found, some of which have a "novelty" function. These were typically found on Viennese-made instruments (e.g. British-made instruments of the period rarely have more than two pedals). Examples include:
  • The lute pedal pressed a piece of leather, wool or silk against the strings to damp vibration, producing a sound supposedly like a lute.
  • The moderator pedal  was a forerunner of the celeste pedal, placing material (commonly leather) between the hammer and strings.
  • The bassoon pedal caused a piece of parchment or similar material to come into contact with the strings to give a buzzing sound, allegedly imitating a bassoon.
  • The janissary pedal was associated with a variety of percussive effects such as a felted drumstick hitting the soundboard, or striking a cymbal or bell. As the name suggests, this was associated with the fashion for "Turkish music" that peaked around 1800 - these effects were sometimes associated with performances of Mozart's "Rondo all Turca". Sometimes there were several pedals e.g. one for a drum, one for a cymbal and one for a bell.
  • The cembalo pedal was a name given to various systems with the objective of making a "harpsichord-like" sound. Certain early pianos even had a second set of wooden hammers as opposed to the normal (at this period) leather-covered ones to achieve this. Another method was a strip of cloth or leather lowered in front of the strings with metal clips on, to give a jangling or tinny effect, a bit more like the sound of a harpsichord. This survived later in the form of a "mandolin rail", a similarly designed attachment occasionally used on pianos in the 20th Century to give a "honky-tonk" effect, though this latter device was commonly lowered into place by hand rather than with a pedal.
Here's a demonstration of some of these effects on a piano from 1815 by the Viennese maker Thym:

And the "Rondo Alla Turca" on an early 19th Century Rosenberger piano:

These "novelty pedals" had largely been abandoned by the 1840s, much to the relief of music critics and many listeners as well!

Saturday 9 June 2018

Piano pedals (2) - soft pedals - una corda, half-blow and celeste

Having dealt with the sustain pedal in my last article on the topic, I wanted to turn to the function of the left pedal (and in some cases the middle pedal if you have one). This time I intend to cover the the pedals on a piano that are intended to make the sound softer, which are of three main types: (true) una corda, half-blow and celeste. I should point out that in music the indication for the left pedal is "una corda" so sometimes this term is used to cover all the types, but in fact the mechanism generally works in a quite different way on an upright as compared with a grand. There are two other common pedal functions (sostenuto and bass damper lift) which do not fall into the category of soft pedals and will be covered in a third article.

So, at this point we need to cover the slightly complex question of what the pedal functions are, depending on whether you have a grand or upright, and whether it has two or three pedals. In the last article, I explained that uprights can have an underdamper action (dampers below the hammers) or an overdamper action (dampers above the hammers). For the purpose of this article, it may be useful to know whether your piano has an overdamper or underdamper action, and whether it is overstrung (bass strings cross over the treble ones) or straight strung (strings run straight up and down the piano). All modern pianos (more or less anything built after 1945) will be of the overstrung underdamper type.

If you don't want to spend time looking inside your piano, don't worry too much as it's usually possible to tell what your pedals do just by listening to them.

If you have a grand piano:
  • If it has two pedals, the left pedal will normally be a (true) una corda, whilst the right pedal is (as always) the sustain pedal.
  • If it has three pedals, the left will normally be the una corda, the middle will normally be the sostenuto, and the right will be the sustain pedal.
If you have an upright piano: 
  • If the piano has two pedals and an underdamper action, whether overstrung or straight strung, the left pedal will normally be the half blow pedal,  and the right pedal will be the sustain pedal.
  • If the piano has two pedals and is overstrung with an overdamper action, the pedal functions are frequently the same as for an underdamper action, but sometimes (but not always) the left pedal is a celeste pedal instead of a half-blow.
  • If the piano has two pedals and is straight strung with an overdamper action (in the UK this is a significant minority of older instruments), the left pedal is in the great majority of cases a celeste pedal, may occasionally be a half-blow, and in a very few cases may be a true una corda, of which more later. The right pedal, as always, is still the sustain pedal.
  • If the piano has three pedals it normally has an underdamper action (I've never seen three pedals on an overdamper, thought possibly a few may exist). In this case, the left pedal is normally a half-blow pedal, and the middle pedal is most commonly a celeste pedal, though more rarely, it is a sostenuto pedal, or a bass damper lift pedal.
Also, on a few (mainly older) pianos with three pedals, the middle one is just a dummy pedal that does nothing at all - generally these are American instruments since, as I had already mentioned, most older European-made pianos don't have a third pedal at all.

The Una Corda pedal

So now to demystify what these terms mean. The una corda pedal was actually the very first device used to change a piano's tone - its history goes all the way back to Bartolomeo Cristofori, the inventor of the piano. Cristofori began building pianos around 1700, and an una corda stop is featured on a surviving piano which he built later on (1726).

To understand how, and why, the una corda works, I have again used this action diagram for a grand piano:
What I've shown here is that the grand action consists of two parts - the main action, which controls the hammer striking the string, and the damper mechanism (to the left of the red line), which comprises the damper rail, damper underlevers and the dampers themselves. The function of the una corda is to move the hammers across slightly, thus striking two of the three strings (on trichords) and one of the two on bichords. This is done by a system of levers (trapwork) underneath the piano that cause the main action to be pushed slightly to the right - the action is returned to its original position by a strong spring when the pedal is released. As the entire action is shifted, the keyboard can be seen moving physically to the right.

The key thing about the operation of an una corda pedal is that the hammers should move in relation to the strings, whilst the dampers should not - these need to damp all three strings exactly as they normally would. This is quite easy to achieve on the grand action as the dampers are separate from the main action, but (as will be seen) very difficult on an upright.

The term "una corda" (Italian: "one string") comes from the fact that early pianos normally only had two strings per note, so the pedal was intended to have the hammers strike one of these. On a modern piano, normally two strings are struck, so "due corde" would be a more accurate term, but the earlier nomenclature has stuck.

This is almost invariably the function of the left pedal on a grand - if your grand piano has a middle pedal it will normally be a sostenuto pedal, which will be covered in the next article.

Half-blow pedal

This pedal is normally only found on an upright piano - it's essentially the "substitute" for a true una corda pedal. Its function is shown in the picture below:


The left pedal operates a rocker which pushes up the pedal stick (the red arrow is pointing to the top of this), the effect of which is to move a hinged part of the hammer rail closer to the strings. As the line of hammers is now closer to the strings, the volume when playing will be reduced.

Though both the half-blow and una corda pedals have the effect of reducing the volume, the una corda also changes the tone (due to striking two strings instead of three); the half-blow simply reduces the volume. Additionally, some pianists may notice a change in the feel of the keys when the half-blow pedal is in use - this is due to the fact that something technically known as "lost motion" is introduced - I won't try to explain this in full here, but it means that the keys will go down a little way before starting to propel the hammer, rather than doing so immediately.

Celeste pedal

The celeste rail on a Yamaha U1, which lowers a piece of felt in front of the strings.
This pedal is also normally found only on upright pianos - its other names included the "muffler pedal" and "practice pedal". Quite simply, it inserts a piece of soft felt material between the hammers and the strings. This arrangement is commonly found as the middle pedal on more modern (and a few older) uprights which have three pedals and an underdamper action, or as the left on older straight-strung overdamper uprights. Please note that overstrung overdamper uprights normally have a half-blow which moves the hammers closer to the strings, just the same as an underdamper.

When found on an underdamper, the celeste rail normally has spring-loaded support brackets that makes it stand above the action, and the pedal lowers the celeste into place. On the older straight-strung overdampers, because the dampers are above the line of strings, the celeste rail sits at the back of the action and is pushed up from below. In either case, the rail normally needs to be removed when tuning - in the case of the underdampers because it is sitting in front of the tuning pins and for the overdampers because it impedes wedging.

A device similar to a celeste (often called a moderator) was a feature of several early pianos - e.g. the Viennese maker Graf included two different thicknesses on his pianos in the 1780s. These were originally made of leather or cloth, sometimes cut into strips to allow the strings to vibrate more freely.

Is it possible to have a true una corda pedal on an upright?

The Wikipedia article on piano pedals quotes a work by Edwin Good, entitled: Giraffes, Black Dragons, and Other Pianos: A Technological History From Cristofori to the Modern Concert Grand, as saying that an una corda pedal on an upright is impossible because the strings "run at such an oblique angle to the hammers that if the action were moved sideways, the hammer might strike one string of the wrong note".

In fact, I do not believe this is the main reason why upright pianos scarcely ever have an una corda pedal. After all, some small baby grand pianos have strings that run at an oblique angle (a few are even double overstrung), yet still have an una corda, whilst even larger or stright-strung uprights hardly ever have one. In my view, there's no reason that problem couldn't be overcome by careful string-spacing and action placement. The real cause of difficulty can be seen by looking at a diagram of an upright piano action:

Upright action diagram - this is typical of an older American upright

The key point here is that the hammer butt (yellow, top right) which carries the hammer, the lever (yellow, lower down), which carries the jack, and the damper body (blue), which carries the damper, To achieve an una corda, the levers and hammers need to move across (the two yellow pieces), but the blue damper bodies need to stay where they are. To achieve this you would somehow have to split the wooden beam so that the part that carries the dampers (and the damper lift rod, which is hinged to the beam) stays in the same place, but the rest of the beam moves across. This would be extremely difficult and fiddly in practice.

So is it impossible to have a true una corda on an upright? The answer is no, though they are extremely rare; whilst it is near-impossible to achieve on an underdamper action, it is perfectly possible on an overdamper, because the dampers are attached to a separate rail above the main action. This is still uncommon in practice, but I have come across a couple of these on my rounds and here is a video of a German piano tuner playing another:



Monday 9 April 2018

Beethoven Broadwood Bicentenary

This year, the firm of John Broadwood & Sons is promoting a celebration of a remarkable gift - a grand piano sent to Beethoven exactly two hundred years ago.

Thomas Broadwood (1786-1861), the third son of John Broadwood was visiting Austria in 1817 and had contacted the famous composer Ludwig van Beethoven whilst in Vienna. He was invited to the composer's apartment, but noted that Beethoven did not have his own piano at the time; rather, he was borrowing or hiring instruments from sympathetic local piano makers. Additionally, Beethoven's deafness meant that he was seeking a louder piano: at the time, the grand pianos being built by Broadwood's in London were capable of more volume and power than contemporary Viennese instruments.

On returning to London, Thomas decided that he would send Beethoven one of Broadwood's pianos as a surprise gift. He enlisted the help of several eminent pianists to select the most suitable instrument - No.7632 was the one eventually chosen - and the piano was dispatched from London Docks on 27th December 1817, to be taken all the way to Trieste in the Adriatic by sea. The piano was kept in a warehouse until April 1818, when the Alpine passes were clear of snow, and then taken the 360 miles to Vienna by horse and cart. Despite being placed in a protective packing case for the duration of its journey, the piano had nevertheless suffered some damage as a result of its lengthy peregrination, and Beethoven recruited the assistance of his friend Nanette Streicher, a Viennese piano builder, to carry out essential repairs.

The route taken by the Broadwood piano on its way to Vienna
The piano was taken to Beethoven's apartment in Mödling, near Vienna, in late April or early May 1818. He was delighted with the gift, but moreover the increased sonority and sustain of the English-made instrument inspired him to employ these qualities in three of his late piano sonatas, Op.106 in B flat, Op.109 in E (the "Hammerklavier"), and Op.110 in A flat (most evident in the composition of the bass part).

After Beethoven's death in 1827, the piano was sold to a Viennese music publisher, C Anton Spina, who kept it until 1845 and then gave it to the composer Franz Liszt. Liszt kept the piano in his house in Weimar until 1874, when he donated it to the Hungarian National Museum in Budapest, where it remains to the present day. The piano was restored to a playable condition in 1991 and is on regular public display at the museum.

Scheduled events (in the UK)

Beethoven recital at the Clarke Clavier Collection, Oxborough, Norfolk at 3.00pm on 28th and 29th April 2018. Mariko Koide will be performing. Tel 01366 328217 for booking (essential).

Lunchtime recitals on early Broadwood grands by students Yehuda Inbat and Amiran Zenaishvili at the Royal Academy of Music Keyboards Museum, London NW1 5HT on 2nd and 9th May 2018 at 2.30pm. Details at www.ram.ac.uk

"A most remarkable gift": Talk and demonstration by Dr Alastair Laurence, chairman of John Broadwood & Sons, also at the Royal Academy of Music Keyboards Museum on 8th May 2018 at 7.00pm. Details at www.ram.ac.uk

"The Vaulted Concert Room": International concert pianist Paul Roberts performs Beethoven and Debussy on a 1921 Broadwood steel barless grand at Finchcocks, Goudhurst, Kent TN2 5LE on 27th May 2018 at 7.30pm. Advance booking essential, see www.finchcocks.com

First concerts in the new recital room at the Richard Burnett Heritage Collection, Waterdown House, Tunbridge Wells, Kent TN2 5LE. On 10th June 2018 at 2.30pm and 6.00pm, young virtuoso Julian Trevelyan plays Beethoven on early Broadwood grand pianos, with commentaries from Dr Alastair Laurence. Advance booking essential, tel 01892 523203.

Events elsewhere in Europe

Beethoven's Broadwood Grand Piano is on display at the Hungarian National Museum, Muzeum krt.14-16, Budapest, Hungary. Open 10.00am-6.00pm every day of the week except Monday. See www.mnm.hulen

Commemorative Concerts at the Thönet Schlössl Museum, Josef Deutsch-Platz 2, A-2340, Mödling, near Vienna, Austria. These will take place throughout April and May, performed by local schoolchildren and professional musicians. A guided tour of Beethoven's apartment at Mödling (where the Broadwood piano was delivered) follows after each concert. See www.museum-moedling.at

Exhibition of Ephemera surrounding the Broadwood gift, in association with the display of an 1817 Broadwood grand at the Beethoven Birthplace Museum, Beethoven-Hause, Bonngasfe, 24-26, 53111 Bonn. See www.beethoven.de

Saturday 6 January 2018

Piano pedals (1) - the sustain pedal

 
As a couple of people have asked me recently, I thought it might be useful to run through a brief history of how the pedals on a piano evolved and the mechanics of how they work. This is the first in a planned series of three articles.

Two pedals or three?

The first question is - how many pedals does the typical piano have? The answer may depend on which part of the world you live in. In Europe, the great majority of older pianos will have only two pedals - only since around the 1970s and 80s has the middle pedal become commonplace on new models. On the other hand, in North America, I understand that three pedals is generally the norm, and the situation may vary in other parts of the world. In any case, almost any piano will have either two or three - a few historic instruments (typically from the 1860s or earlier) may have only one pedal (normally the sustain pedal); also in a very few cases there may be four or more (of which more in a later article).

The exact functions of pedals on an upright piano is typically different from a grand piano, and some uprights differ from each other, so to ease into the discussion I'll deal with the one pedal which does more or less the same thing on every piano, and is almost always located in the same place - it's the right-hand or sustain pedal.

The sustain pedal (right-hand pedal) - also called the damper pedal

When pianists talk about "using the pedal", it is the right-hand or sustain(-ing) pedal they normally mean. This has a similar function on more or less every instrument, which is to lift off all the felt dampers that prevent the strings from ringing on after being struck by the hammer. Because of this, the pedal is sometimes referred to as the damper pedal or the loud pedal, though the latter term is often held to be incorrect since it does not make the notes any louder; nor is it the pedal's particular purpose (it is often used in quiet passages). However, its use does change the timbre of a note when struck, as it allows the strings of the other notes to vibrate sympathetically. On some early pianos, the sustain pedal is the only pedal though it was not the first to be invented (that was the una corda, of which more in the second article).

The first maker known to have used the sustain pedal mechanism in essentially its current form was Johann Andreas Stein (1728-92), although his pianos featured knee pedals rather than the modern foot-operated ones. This was a development of an earlier idea by Gottfried Silbermann (1683-1753), but this earlier device was a hand stop, so could only be switched on and off whilst the piano was not being played. A picture of a Stein grand piano, with the knee pedal visible, can be seen on the Cobbe Collection website here:
http://www.cobbecollection.co.uk/collection/15-grand-piano/

John Broadwood in 1783 used the modern concept of the sustain mechanism operated by a foot pedal on his grand pianos, though this may have been used on some earlier English-made instruments.

How the sustain pedal works

Although this pedal has the same basic function on every piano, it actually works in a slightly different way depending upon the type of piano you have. 

Underdamper uprights (all modern and some older uprights)

All modern upright pianos and some older instruments have dampers that are located underneath and behind the hammers - this is called an "underdamper action". This picture shows the bass section of a Yamaha U1 - I have pressed the pedal down and as you can see, the dampers have come away from the strings (the position of the dampers is shown by the red arrows).


When the pedal is pressed, it moves a pivoted rod (usually wooden on older pianos, sometimes metal on newer ones) called a rocker, and this pushes up the pedal stick, normally at the left-hand side of the case.
This picture shows a typical arrangement of two pedals, the pedal rockers and pedal sticks on an older German-made upright piano. When the pedal is pressed down, the pedal bolts pull down the pedal rocker at the right-hand side - the left-hand side pivots up raising the pedal sticks (at the left side of the case).The rocker is returned to position by a spring.
The pedal stick engages with a hinged metal rod at the back of the dampers, called the damper lift rod, which pushes the tails of the dampers forwards and brings the heads away from the string.

This picture shows a modern Yamaha U1 action from the back, removed from the piano so you can see what is happening. The pedal stick comes up where my hand is and the rod (the end of which can be seen under the green arrow) moves the damper tail outwards, moving the head back from the string.

You will also note that the top notes (typically the top couple of octaves) on any piano will not have dampers, as they sustain for such a short while that damping is unnecessary.

The invention of underdampers goes back to 1829 when they were featured in an action design by the French piano makers Blanchet et Roller.

Overdamper uprights (some older pianos)

An 1890s German overstrung upright with overdampers
If your upright piano looks a bit like this with the top door removed, you have an overdamper model. Overdampers are very common in many European-made pianos from before the Second World War, but the design gradually disappeared over time and ceased to be made at all after about 1950 (outside Europe I believe they may be much less frequently-encountered). They can very easily be identified by the long wires at the front of the action which operate the dampers, located on a separate damper rail above the line of the hammers. Unlike the underdamper action, which relies on springs to push the dampers back on to the strings, the overdamper mechanism is gravitationally operated (there are often weights located in the wooden damper bodies). Please note however that some older pianos - including pre-1900 models - have the modern-style (underdamper) mechanism.

On these pianos, the dampers are normally lifted by a wooden or metal rail underneath the damper bodies - the blue arrow on the diagram shows the end of the damper lift rail and the top of the pedal stick (which is pushed up by the pedal). The damper body (the piece of wood connected to the top of the long wire) links to a right-angled wire that connects to the damper head.

There is some variation in these arrangements - a few (normally older) overdamper models have a spring-loaded damper rail which is pulled away from the strings, or a hinged rail which moves upwards with the pedal, drawing back the dampers in both cases.

Overdampers are similar to a design used by Robert Wornum in his patent for a "double action" in 1826, which is the basis for all modern upright actions. It appears that most English manufacturers used this design through the mid-nineteenth century, whereas some French makers used underdampers; quite a lot of German makers followed the English practice. From the latter part of the nineteenth century onwards until around 1950, overdampers were gradually phased out as more and more manufacturers switched over their action designs. However some noted makers (such as the German firm Blüthner) continued to use overdampers until relatively late on.

Grand pianos

On a grand piano, the dampers sit on top of the strings (except for a few older models that have them underneath) and are easily visible when the lid is raised. Each damper is connected to a wire, which goes through a hole in a piece of wood through the damper guide rail, and connects though a pivoting knuckle to the damper underlever, which is attached to a rail underneath the soundboard. Note that under normal circumstances these underlevers are difficult to see with the action inside the piano.

This arrangement is shown in the diagram below:



When the key is pressed down (the front of the key is off the right-hand end of this diagram), it pivots on the balance pin (coloured blue) and the back of the key is pushed upwards (red arrow). This will propel the hammer up toward the string, but the part we're interested in here is that the very back of the key (shown in red) will rise up and push up the damper underlever, so lifting the damper head (green) and felts from the string.

If the pedal is pressed, this typically connects to a metal strip that pushes up a dowel underneath the damper lift rail (shown in orange) - this raises all the damper underlevers and the dampers (green), regardless of whether the key is pressed down or not.

You will also note that in the grand action, the damper mechanism is effectively separate from the main action, which will be important in the next article!

When the sustain pedal isn't working

The pedal is extremely important for expression in many piano pieces - especially those from the romantic era - so pianist Eliane Rodrigues had to think on her feet when things went wrong during a performance in Rotterdam. Here's what happened when the piano had to be taken off-stage, using a descending trapdoor, and replaced:


The other pedals (left pedal and middle pedal, where there is one) will be covered in two further articles.