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Posts tagged distance

The Una Corda Pedal – The Soft Pedal

Piano Price ~ August 2017
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The Una Corda Pedal and How It Works

A few months ago we examined the mechanical and musical basics of the damper pedal. This month we’re going to look at how the una corda, also known as the soft pedal, works.

Manual-typesettingI was speaking with an older gentleman recently who used to be a typesetter for a newspaper, meaning that he would manually place letters in rows each day for the daily newspaper (pre-computer and pre-typewriter). Each of the letters in the alphabet was grouped together and were called “sorts”.

As the day progressed, depending on what the typesetting would require, you might run out of a certain letter, like a letter E or letter A, for example. And so if you were “out of sorts”, meaning that you had run out of that particular letter, you would go into the storage room of letters and get more sorts, another container of that character. The insinuation is that if you’re “out of sorts”, all production stops until you remove yourself from your work, restock and regroup and then continue on. I love these kinds of stories that reveal the story behind the phrase.

The soft pedal on the piano also has not-so-quaint a story but interesting nonetheless. Cristofori, credited with the invention of the earliest pianos in the 1700’s also installed the “una corda” pedal into his pianos. Being Italian, the phrase “una corda” can be translated “one string”. How does “one string” translate into a pedal we also know as the soft pedal? We’ll look at that in just a moment but first, let’s take a look at the structure of the left pedal on the piano called the soft pedal or una corda.

First of all, grand pianos and upright pianos have very different functioning soft pedals. The grand piano shifts all of the keys from left to right slightly. As you can see in the top picture, the keys move away from the rim at the left. This, in turn makes the hammers off center from the strings they are striking. What’s happening below the surface is that the soft pedal (the left pedal on any piano) is connected to a rod which eventually joins to a lever that swivels. This swivel piece sits under the entire keyboard frame and moves all of the keys from left to right. Why shift all of the keys? On the majority of the keys on the piano there are 3 strings. When you shift the keys using the soft pedal, the piano hammers strike only 2 strings (pictured in the second frame) instead of 3 and thus, the piano becomes softer. But what is also simultaneously happening is that the hammers, being shifted out of their usual strike pattern, are also hitting on fresh felt. When the hammers are aligned to strike at the normal position, they will, over time, have small grooves in the felt. When the soft pedal is engaged, shifting from left to right, the hammer is no longer striking those same grooves. The effect then is that the tone is usually quieter but also softer and warmer in timbre.

Mechanically, upright pianos operate very differently and the soft pedal on any upright is not really any kind of “una corda” since it does not shift the keys. Rather, it pushes the hammers on a single rail forward towards the strings (pictured below). How do closer hammers make the piano softer? It simply gives you a bit more control bridging the smaller gap between the hammers and strings. Hammers on an upright piano travel the full distance to the strings under normal conditions. When they are moved closer, the idea is that with less distance to travel, it will be easier to control. Try this as an example: if you wanted to clap your hands loudly, it is our natural inclination to first separate our hands a fair distance to make the impact greater.

What happens if you move your hands only a foot apart and aren’t allowed to move back before you clap? The result is that the lower distance only allows for lower impact and thus lower volume. Upright pianos work the same way. When the pedal is depressed, a rod simply engages a rail that moves all of the hammers closer to the strings in hopes of limiting the loud playing and making a closer strike distance. The result is quite often negligible and the tone, unaffected compared to a grand piano moving the hammers onto fresh felt.

So where does the term “una corda” come from? Back in the day of Cristofori (early 1700’s), each note on this primitive piano had only 2 strings. Using the “una corda” shifted the keys so that they would only strike 1 string. How different the piano would sound if you would only strike one string at a time. It would sound not only quieter but also thinner. Our ears are so accustomed to hearing 3 strings simultaneously, it would actually be odd to hear a single string resonate at a time. It would be more akin to a guitar. Over the years, however, the term “una corda” has become an anachronism. Although it’s outdated, the term implies quiet and more intimate playing. I guess we could start a quiet revolution and call it Due Corde (2 strings)… but then again, the initials DC are already taken meaning Da Cappo. Piano nerd humour. Hahaa.
As an aside, if you ever get a chance to visit the keyboard museum in Vienna, Austria (Kunsthistorisches Museum Wien), the instruments dating from the 1700’s are completely fascinating and being able to see the historical developments up close is incredible. I highly recommend it!


Bringing Your Piano Home

Piano Price ~ July 2014
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Piano PlacementSo you just purchased a piano. Now what? It’s kind of like bringing the baby home from the hospital; you need to give some thought as to the inclusion into your life. What about placement? Where do you put it? And how about maintenance? How much and how often does it need to be tuned? This month, we’re taking a brief look at piano follow up in your home.

Placement and Positioning

I’ve quite often said that pianos are like small elephants. As a piece of furniture, they can dominate a room. First off let’s debunk the old ‘outside wall’ business where many have been told pianos cannot sit on the outer wall of a house. Back in the 1920’s, old houses didn’t have sufficient insulation and in winter, outside walls had as much ice on the inside of the wall as the outside. Fluctuations in temperature were enormous and pianos weathered much better on inside walls. This is not really applicable today. General rule of thumb, if you can touch the wall and it feels like room temperature, you most likely don’t have an issue because modern construction and insulating have effectively buffered outside extremities. There are, however things to consider as danger zones: direct sunlight, baseboard heaters and fireplaces. Direct sunlight will not only create fluctuation in temperature and humidity and affect the inner workings of the piano but it will quite often fade and damage the outer finish.

Baseboard heaters are a no-no for close proximity. They heat up and cool down constantly. Finally, being in a confined space with a fireplace or wood stove also dries out parts and the sound board of the piano. If you have an upright piano, don’t position it close to the wall and in doing so ‘cup’ the sound. General principle is to have the piano about a fist’s distance from the wall which ensures proper displacement of the sound. Do also consider acoustics of the sound as well. Hard wood floors will echo while carpet and drapes absorb sound. Plaster and glass contribute to the echo. Grand pianos sound great in corners as the tone reflected off of the lid will be heard as it reflects again in the corner.

Piano Preparation

Hammer Flange

What exactly is piano preparation? If all of the notes play and work properly, why do I need to put work into a new instrument? Let’s just say that manufacturing involves assembly and some levels of preparation. Final preparation is the last stage of adjusting a piano to its home environment. Having a piano moved half-way around the world, it has been bumped and jostled. The wood at the factory quite possibly has different humidity levels to your home and so out of the approximately 5000 intricate piano parts, some may be 90% tight but rarely are they 100%. Let me give you a small example: the hammer that strikes the string is attached to a round stick called a shank which rotates via a steel center pin on a small wooden piece called the flange. This flange is screwed into a common rail appropriately called the hammer rail. It’s my experience that if the flange screws are not completely tight, you lose transference of energy and will quite often result in audible clicks even if they are a quarter of a turn off of tight. “Well why would they become loose by simply moving the piano?” It’s not that the screws have undone, it’s that the wood has settled or cured, possibly absorbed or released humidity subsequently resulting in looser parts.

Preparation involves double checks on these screws as well as plate and action screws and the alignment of action parts. Also significant is the ‘seating’ of strings – making sure they are tight against the bridge. Bringing pianos to proper pitch for the first time is also part of that process. Finally, voicing the piano – making it sound brighter or mellower – adjusting the tone so that it is suitable in your home environment is significant.

Piano Preservation

Piano Bass Strings

“So… how often should I have this done?” are usually the words clients say to tuners as they’re putting on their shoes and closing their toolkits. Great question. If you’re a new piano owner, there quite often is abundant stretch in the new steel strings. You wouldn’t think so, but new piano strings will stretch for quite some time. Subsequently, tuning new pianos more frequently in the first year is always beneficial. Usually your first tuning is included with a piano purchase from a retail store. My advice? Tune another 2 times your first year and you will have a very stable instrument long-term. So what happens to strings with stretch? It’s a little like a tug-of-war. You stretch the strings and the strings pull back but not as far (often by about 1/3). You tune again, and again the piano will pull back but not as far. By the third tuning, you should have more consistent pitch. After that how often should you tune the instrument? This varies considerably from location to location and piano to piano (and person to person…lol…some people are just really picky :D) In more drastic climates, where it gets really cold and then quite warm, pianos could be tuned twice a year just following the major changes of ‘freeze’ and ‘thaw’.

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