@@Vinvillivix Cristofori invented the single escapement action around 1700. This is the improved version, the double escapement action invented by Erard in 1822.
If you want an "engineering class" related to pianos, look at videos that tell you how to properly tune this marvel of wood and steel. Even the way you place a tuning handle on a tuning peg can effect if the piano stays in tune after loud playing. Also, some knowledge of harmonic series in the 12th root of 2 helps. Now THATS an engineering class [smile].
Fret not (pun intended). I am going to make my own demonstrator with slow motion to show how this intricate mechaisum works, loud playing, soft, playing, rapid repeat, and even how the pedals effect the action.
I've always been a huge fan of piano music (especially jazz) but I never really knew how they worked. This was pretty cool, I learned a ton. I wasn't very excited bc I had to watch it for school but this was awesome! Thanks a ton! :)
Nice explanation! Just to make things a bit clearer for viewers of this video: The blow distance (the distance the hammer travels from its resting position to the string) is typically about 46 mm. The jack might, so to speak, start to prepare for slipping away from under the knuckle in the last third of the traveling towards the string (as mentioned in the video), but the actual point where "the click" happens (called let-off) is as close as 1.5 mm to the string in a well regulated grand (a little bit further away in the low bass.) The click sensation is experienced when the hammer drops down from let-off about 1.5 mm (called the drop level, thus about 3 mm from the string), ending up resting on the repetition lever, ready for fast repetition of a single note. This is, apart from the una corda pedal, the biggest difference between a grand piano and an upright. A grand piano allows for a new strike much sooner thanks to the repetition lever, when the key is released just a few millimeters from the bottom position, whereas on an upright, the key needs to be released basically all the way up to allow for a new strike.
You seem to know piano actions very well. Can you tell me how the sustiano pedal keeps the dampers up for notes pressed before the pedal is pressed and not interfere with the dampers for other notes to raise and drop as notes after the pedal is held down? I want to build my own demonstrator that shows how the 3 pedals work at the action level. The sustiano is what people describe WHAT it does but not HOW at the action level. Thanks
@@paulromsky9527 I could, but there's a pretty neat video clip here on YT where you can see it all animated! The small tab on the damper lever that you mentioned in a comment above is solely used for the sostenuto mechanism. Watch this: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-6effL4ATZVo.html
@@iaspati610 Patrick, Thanks for the links! I am starting to draw my design now. I hope to start cutting wood in a couple of days. I am going to make mine out of Maple because I can get it at Home Depot or Lowes and not have to go to my local specialty lumber yard which is 30 miles away. I would love to make it all out of Delrin, but I don't have a milling machine. I was going to make my bearings out of Teflon, but after learning about the "Steinway Fiasco", I am going to stick old school and use felt. Paul
@@paulromsky9527 The invention of the double escapement system is due to Sébastien Erard in France about 1820. Later inventors only added minor details. In fact the original mechanism is surprisingly similar to that of 200 years later. The Erard is even superior in 2 ways: contrary to modern piano's it is possible to take out the keys individually and the damping system in its entirety, greatly enhancing ease of regulation and maintenance.
Yes, you should build one out of Legos. If you do, you may get published in a magazine! My friend made an Antikythera Mechanism out of Legos and his video was made by Nature Magazine.
Hello and thanks for the informative video :) Maybe you can shed a light upon a question about the piano action that I can’t quite solve. To my understanding the hammer has to be accelerated to a certain minimum speed otherwise it will not be able to reach to the string and thus it will not produce any sound. Also to my understanding the volume of the sound depends only on how fast the hammer gets accelerated by the key and therefore how fast it hits the string. Now here is where I have difficulties to grasp: how is it possible to play (very) fast runs or trills not only loud but also silent? Eg.: you can play a certain fast passage f or ff but you can also play it mf or mp. So here is my comprehension problem: in all cases the passage is played at the same speed which means that the fingers have to “fly” at the same speed over the keys. Essentially (in my understanding) this would mean that in all cases the keys are accelerated by the fingers at an identical speed. So how is it possible that we still can produce different volumes? Where is the point that I am missing? Many thanks in advance
I believe it simply has to do with the amount of force you play with. If you keep your fingers close to the keys and play gently using only the strength of your fingers then the speed at which the hammer travels to the string will be less. But if you raise your fingers higher before striking the key and lean forward into the keyboard as you play, using the strength (and weight) of your arms and shoulders then the hammer will move much more quickly (with more force) toward the string. All that extra energy being transferred to the string will produce a louder sound.
@@MoreWordsPlease, what I know is pianists should play fully to the bottom of the key. I'm thinking digital pianos should have optical sensors that measure the speed of travel between two points, not just a contact sensor.
Great video. You explain the mechanisum very well. I know that the sustain pedal simply lifts up all the dampers. In your demonstrator, there is a small L shape piece of felt on the damper lever. I assume this is where the sustain pedal will cause a bar to lift up all the dampers. Am I correct as to where that occurs? It would be nice if you could mention this in a follow on video. You don't have to demonstrate it, just describe how the sustain action works and point to the area. I know the soft pedal just shifts the entire keyboard to the right a small amount so that the hammers hit only one string of the two string notes, two strings of the three string notes, and still hit the one string of the single string notes. Ok, that is easy to understand. What is hard to understand is how the middle sustiano pedal keeps the dampers up for notes that were held before the pedal was pressed but still allows the other dampers to raise and lower as subsequent keys are pressed and released after the pedal is held down. How does that part of the mechanisum work? I am sure it is as elegant as the rest of the action, but I can't figure out how it works. Could you demonstrate that, or at least mention it in a follow on video? Thanks
Romsky If you could explain how the 3 pedals work with the action, you would be the first person on RU-vid (that I could find) that does that. I see a lot of videos that describe WHAT the 3 pedals do, but not on HOW they work at the action level.
The way it works is by catching the L shaped red felts on the dampers into a shelf-like part of a comma-shaped profile bar (isn't presented in this video). The bar can rotate by the press of the sostenuto pedal, and rotates the "shelf" towards the damper felt strips. When the keys are pressed and dampers raised, those felt strips can be caught on the "shelf" of the sostenuto bar by pressing the sustenuto pedal. After pedal hold and key release, the felt strips lay on the bar's profile ("shelf") and the higher located damper felts don't rest on the strings only on previously pressed keys. The other key's dampers have their red felt strips under the bar's profile, and don't get caught in raised position. The wooden part on which the felt strips are located apparently can pivit down, allowing the other "uncaught" dampers to fully raise and not bump into the sostenuto bar. After pedal release, the raised dampers can drop. On this image, part 14 is the comma-shaped profile bar that the sostenuto pedal rotates, and part 35 is the sostenuto tab that gets caught. The part 47 (damper lift rail (sustain pedal)) is shown a little bit confusing and maybe incorrectly though. All it does is lifting a rail that lifts all dampers, so it's not such a bad picture. pianoworld.com/wp-content/uploads/Images_for_Various_Pages/Grand_Action.jpg Here's a great video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-6effL4ATZVo.html
Could someone explain to me why we need such complicated machinery to achieve a seemingly simple task - raise the hammer to hit the keys? Why there are so many additional levers? From what it seems, only the hammer, the primary lever (the keys) and the damper is required..
As a piano player I assume some points why it's a bit more complicated than a simple lever mechanism. 1. The hammer shank needs to be immediately "removed" from the string, otherwise the sound will suddenly stop. -> you keep pressing the key when you play a "long note" 2. When you want to repeat the same key immediately, it needs a component with a low Inertia. Also note that if the hammer drops down to its rest position, it would take too long to play same key. I hope I helped a bit. The mentioned points are NOT researched.
Very well stated. The hammer has to be tossed up and bounce off the strings and allowing it to be thrown at different speeds (hence the name piano-forte soft-loud). Also the dampers have to raise and lower, and a rapid repeat needs to be allowed. Put all that together and you need more than a simple lever...and that is why we have such an elegant and intricate system of levers. The piano is an elegant and so versatile instrument.
Just a quickie...key sticks are not made of maple. They are made with either pine or spruce. Steinway has never made a keyboard with maple. Their pre-WWII pianos had pine keyboards manufactured at the NY factory in Queens, Astoria, NY. Post-WWII, they used keyboards made with pine and manufactured by Wood and Brooks through the 50's, and Pratt-Read thereafter until 1984, when they began to use spruce keyboards manufactured by Kluge of Germany. Kluge has since been acquired by Steinway, and their keys may be found in both New York and Hamburg Steinway pianos.
Very good, 5 mins went too quickly! What I was expecting to see, was the repetition action. It was mentioned but not really shown. I only found out about that difference compared to the upright piano yesterday, so I'm interested in seeing how the repetition works.
I agree. It would be nice to show how the repetition part of the action works. It looks like after the tip slides off the knuckle (most I think are actually rollers), the repetition arm takes place of the knuckle (about half way) so if the key is released half way and pressed again, the hammer is already half way there and thrown up again - thus not requiring the key to be totally released to replay it. This allows rapid repeating of a the note. I asked if he could add on how the pedals affect the action as well.
You can see in the model that the key is down at the back and up in the front which creates the tilt. The hamer is actually flipped at the string. There is no direct connection between the key and the string except when the hammer freely strikes the string with no actual connection to the key. Digital pianos don't have an actual escapement.
I think that the tray in the piano - where the action assembly sits - may have a counter tilt. So, when inside the piano the keys are level. I think the builders of the demostrators are more concerned about showing the action - they are made for the piano store to help up sale the more expensive pianos. I am building my own demonstrator, so I be sure my keys have no tilt when at rest. Also, mine is going to show how the pedals interact with the action as well. I am even going to have real strings, bridges and tuning pegs for the full effect. Then I will make a killer video with a full up tech trainer model, not something just to help sell pianos.
Would you please shed some light on the topic: Does install a player system on a piano impact the touch, the pedal, and the sound quality of the piano? Appreciate your insight!
A good player system install *shouldn't* impact the touch of the piano or the tone quality. Depending on your brand of piano and the installer's method, experience, etc.., it might change the feel of the pedal slightly - often the pedal trapwork has to be cut to allow the pedal solenoids to "intercept" and operate the pedals. A good technician can adjust this so that most players don't notice the feel, though.
ok so that's why i sometimes don't hear the note being played even though i'm sure i pressed the key...i didn't know i had to launch the hammer! 😂 i thought as long as i was pressing down fully on the key, the hammer would hit whatever it needs to hit to make the note ring
My piano down weights are very light, yet the inertia - getting the key started - is very strong/hard/heavy. How can I reduce inertia, or the force needed to get the key moving? Almost painful to play advanced music with an action that takes a LOT to get the key moving. Shouldn't be so difficult, especially with low down weights. Thank you.
Hi, very good explanation. My grandma's piano have some pianokeys that are "tired". They are half way down and when I press them I get no sound. So I have to drag the keys up a bit and the I can play on them for a little while, especially if I play forte fortissimo on it (then, the key doesn't get in the half pressed position), but it is frustrating to play like that of course. And after a while the keys gets half way down. What parts on the key-construction may be torn/unfit?
There are so many factors that can cause a myriad of problems. I would have to be in front of the piano and lift out the action to see what is wrong. But the frame in front of the keys can warp and cause the keys to bind. Shimming the frame may help, but it has to be done carefully. There are 4 common factors that affect pianos: temperature, humidity, shock/vibration, and..... smoking! If the piano is in a home of a smoker, that will bring on all sorts of problems. Pianos should be kept at a constant 72 degrees F, 50% Relative Humidity, on a very solid and flat firm floor away from dust, vents, vibrations, direct sunlight.....and above all....no smoke. Ask a piano tech for a 1970's piano bar and you will hear the horror stories.
