How a Grand Piano Action Works

[@jedwards1211]

I looked for the longest video about piano action hoping it would cover all the technical details and boy did you deliver. This is tremendous!

[@donaldaxel]

The section I needed was explanation of "roller" (or knuckle) and the two screws for "stopping" repetition and jack, therefore called double escapement, and enabling hammering the string again even if the key is not back to rest; it is at 14:00 Thank you for this comment - it's in the middle of the night and I doubted if I should use 15 min. or sleep to be fresh tomorrow! :)

[@kazemdavoudian2564]

Thank you for the great description. That is really interesting , The person who made this mechanism several centuries ago was really a genius

[@JuanRamónSilva-Piano]

This was the most throughout and ordered explanation I have seen of this marvelous mechanism. Many thanks to you, for explaining so well something that was making me scratch my head so much.

[@victor74293]

That's the best explanation I've found so far. Thank you.

[@robertgrijalva7158]

Thank you! I worked hard on the script so that I could make it really clear.

[@phillewis3108]

This is a brilliant video!

[@droughdough]

This is fantastic. An extremely lucid and thorough explanation of the mechanism.

[@robertgrijalva7158]

Thank you! I'm glad you enjoyed it. I know that my production values aren't the highest (a towel in my basement as a back drop), but hopefully I made it up in the content of the video!

[@SergieRachmaninoff]

That was incredibly insightful. You're a great teacher!

[@robertgrijalva7158]

Thanks. I try to be as clear as possible. Your comment is gratifying! RG

[@Jason-on4hg]

Damn, this is insanely educational. I just bought a used piano off craigslist and want to renew it myself. This was a great, id-depth crash course in how piano action works. Cheers!

[@robertgrijalva7158]

Thank you for your comment. I have tried to be as clear as possible for the students in my classes. I appreciate your feedback. RG

[@notafanboy250]

What a fantastic video. You are a great instructor. The pacing of each individual explanation of components was spot on. Thanks for taking the time to make this.

[@kristopherdetar3552]

Fantastic presentation. Wish I had this much detail given to me 10 years ago. Thank you Sir !

[@THEBIASEDCOMPOSER]

Thank you so much! Every single time I am amazed at how incredibly all the parts of the action are interacting to create a flawless performance! Without all this effort being put into creating a perfect action, and without the technicians to make it work perfectly well, pianist would not exist! Thank you again!

[@normanvesprini]

Thank you for recognizing that it takes technicians with great skill to make piano actions perform in a way that meets the demands of artists around the world!

[@timbabcox6581]

Getting my regulating tools tomorrow and I'm going to be studying piano regulation and tuning. I need to get an action model. This was extremely helpful in understanding how a grand action works! Fascinating and very educational. Thanks for posting this.

[@loganishere4760]

Wow there sure is a plethora of useful information here for an aspiring piano tech.

[@levim.3505]

1:15 Absolutely valid point, but there are still some remarkable pianists that I have spotted doing this, Seong-Jin Cho for example comes to mind. Tremendous technique and I highly doubt he doesn't know it's pointless for achieving "vibrato". I reckon some might do it to force the finger to be relaxed instead of tensing up when holding a note?! Just an idea 😄 Thank you for this video!

[@drewwilson6839]

Wonderful video. This musician turned engineer enjoyed it very much and learned a lot. (BFA Music Performance and BSEE) .

[@robertgrijalva7158]

Thank you. I really appreciate when an engineer takes a look and validates what I’ve got. I really appreciate it.

[@naokookadahill5639]

This video is great ! Thank you so much

[@normanvesprini]

Well done. I learned a thing or two!

[@raidenten6718]

Thank you very much the best online teacher.

[@cserohs]

Exactly what I was looking for....I am an engineer....so have to know how it works !!

[@matthewfargen3753]

Thanks! this explained to me the function of the drop screw for the first time. I did not realize it is the second escapement. I have a similar model which came as a kit and the drop screw did not seem to serve a purpose.

[@robertgrijalva7158]

Actually, to be precise about it, the drop screw isn’t “the second escapement”. The drop screw is a “thing”. Escapement is an “action”; namely the jack sliding out from under the knuckle. The “double” in “Double Escapement” refers to the fact that the repetition lever was added to the grand piano action, requiring the drop screw that is added for the purpose of defining the limit of the rep lever’s movement. As such, there is not another escapement happening; just the one and only escapement, namely when the jack flips out from under the knuckle.

[@paulromsky9527]

Bravissivissivissimo! I am going to build my own, but I am going to have 3 pedals (at table top level) to show the sustain, soft, and sustenuto actions. I will also have a removable string bridge with real strings and tuning pegs and 3 different inserts: one for 1 string, one for 2 string, and one for 3 strings. I can use this to show sustenuto as well as tuning. I will also put in a little sound board. It may not do much, but it should show the concept - it is a key (pun intended) part of a piano. Thanks for the inspiration. I guess the sustenuto is done by throwing a pin under the little flip lever when the note is played, thus holding the damper up after the note is released. The lever gives way to notes that are played after the sustenuto pedal is held down. But suppose the pins are thrown out just as the lever reaches the height. Would that cause binding and possibly damage, or are the pins spring loaded? Thanks, Paul

[@paulromsky9527]

I also see on your device, the key is tilted up at the playing end when at rest. But in a piano, the keys are level when at rest. Is there a counter tilt inside the piano to tilt the rear of the action base when in the piano thus making the keys level at rest?

[@paulromsky9527]

I have a Yamaha DX7 synthesizer with after touch. So I get all sorts of pitch and volume vibrato on it. But I sometimes wiggle my fingers on piano keys as well, but mainly for timing...and to hear vibrato in my head...it is amazing how we can imagine sound and recall pitches. I guess that is how Beethoven could still compose music after going nearly deaf.

[@robertgrijalva7158]

When you do, please send me a photo or KZbin link so that I can see your creation. It ought to be quite impressive.

[@robertgrijalva7158]

@@paulromsky9527 Actually, the keys in a piano are tilted upward. They have to be in order not to pass below the horizontal plane when depressed.

[@benjaminniemczyk]

There is no question that Dr. Grijalva is a master and knows what he is talking about, but the 'how a grand piano action works' isn't really arrived at until 15:00 into the video. The rest is useful piano technician information but doesn't really explain what, why and how of the piano action. I am sure this is intentional on the host's part, I just wish the explanation would come sooner and then the parts explained. This my personal preferred sequence of learning, to show how something works and then dissect it. But I won't complain, Dr. Grijalva knows his stuff and I am sure is beloved by his students.

[@kiwixuerong7383]

very nice video 😆 learned a thing or two!

[@kodfkdleepd2876]

The reason the design is what it is is due to evolution. Rather than start from scratch when there is a new problem or a new understanding one adapts. Through the process of evolution small changes can add up to a significant effect. One can easily accomplish the same effect fewer parts but requiring more complexity and modern tech. This is basic systems engineering. There are only two things going on, the hammer hitting the string(simple impulse theory which is extremely simple and straight forward) and then the performance aspects which is in the area of optimization and fine tuning. A lot of man hours were put in to adapt early primitive designs which handled the main effect(that of making a sound) in to adding a benefit to either sound quality or performance quality. In fact there were many extension that were lost yet were actually beneficial(but not popular to the masses) or detrimental. There's many ways to skin a cat.

[@DonnaChassie]

300 years of piano building! Are You telling me, these parts, You have so nicely demonstrated, are, basically standard parts? Big or small pianos?

[@myuncle2]

Your Magic line is wrong, on the line it's not the half capstan, but it should be the point of contact between the capstan and the wippen heel cushion.

[@diegoalemiguel6271]

let s say alleluha to the Lord cause of you and your epic tutorial🎉

[@robertgrijalva7158]

Thank you. I appreciate it.

[@kyimedical]

What is the standard length of the key are they varies concert piano grand piano and baby grand piano?

[@robertgrijalva7158]

The length of piano keys does vary. A nine-foot concert grand does have longer keys than a 5ft 1 inch piano. But, it would impossible for me to tell you how much this can vary. Different brands of piano have different measurements they work with. Grand piano keyboards are not perfectly rectangular, so bass notes have longer keys, as a general rule. But the same principles apply to big and little grand pianos. The key ratio of 2:1 would still be something to aim for, whether the keys are long or short. Also, the magic line and the power line would still be operating principles. In upright pianos, though, all the keys are the same length. They tend to be that way because upright piano keys are generally designed in symmetry with the case. It would look kind of odd if the bass side of the case the were to poke out further than the treble side. But, I'm no expert on upright piano geometry. My work is 99.9% Steinway grand pianos. I am admittedly ignorant to most upright piano action theory.

[@vicpinto1970]

Where can I get a model of the action? Would love one for my piano room.

[@robertgrijalva7158]

I'm flattered that you like my model. I built it for my daughter. She's a music therapy student at University of Dayton.

[@Mike--K]

I had no idea how complex the key action was.

[@3amsleep]

2:26 actual explanation start

[@marcusvaldes]

What is the purpose of the let off? The one part I don't understand.

[@tomrotelli1355]

Let off adjusts the power of the hammer. If the hammer lets off too soon you lose power to the string and can affect the tone and voice you are getting. Too close let off and the hammer will block onto the string. Think of it like throwing a ball, you don't want to release the ball early or you lose power, you want to release it at the very end of your pitch.

[@marcusvaldes]

@@tomrotelli1355 Excellent explanation. Thanks!

[@adriansue8955]

Why so complicated? what all the intermediate levers? couldn't you rest the hammer roller directly on the capstan, to create an up/down motion more directly?

[@erelsappir900]

If you do so, you won't be able to sustain a note. The hammer will keep touching the string until you release the key, stopping the string from vibrating.

[@somasabul3883]

The action by a pianist to imitate vibrato on a key is not for the benefit of actually creating a vibrato. It is used for the pianist for expressive purposes for their own use.

[@robertknox1991]

Austin C. “the claim that you are only talking about vibrato” …… I think you should re-listen to that part of the video again. He says exactly that he is talking about the desire to add vibrato by wiggling a finger on the depressed key. I’m not sure why you are having difficulty hearing and remembering his exact words and then claiming he said something else. After all, you can re-play the video all you want to get the details down if you need to instead of twisting things to make your own unrelated claim.

[@studentjohn35]

Nooooo! All 3 legs on FIRST, pedals on AFTERWARD. Tipping a piano over on the lyre is the lazy way and harmful to the mechanism and structure.. I'm glad these movers are nowhere near where i live.

[@robertgrijalva7158]

I think you are responding to someone else about the topic of moving a piano. I do not have any videos about piano moving on my channel. Sorry.

[@studentjohn35]

Sorry. my laptop/tracpad was acting strange on KZbin in the wee hours last night. -John, the old Bechstein guy@@robertgrijalva7158

[@kodfkdleepd2876]

A lot of this at the start is nonsense. One doesn't have to have a clue on how something works internally to know how to use it externally. Look at all the people who drive cars, 99% have no clue how a car really works. In fact, you don't have to know how something works to know how to use it. That is kinda the point in some sense. If we did we could never get anywhere in life as we would have to learn everything to the infinite degree just to use it effectively. Sure, knowing how something works internally can speed up learning in some ways and cases and such but given the amount of time a piano player practices it is almost surely that they will develop an internal feel for what is going on with never truly knowing the details. There really is very little a pianist can do to a key. He just moves his finger down. All the "action" is translated in to how he perceives the effect which we call "staccato", "legato", "accent", etc. Hence why a child can play a Mozart sonata extremely well without having any idea of mechanics. As far as "vibrato" holding down a key, as an example, it is irrelevant if a pianist thinks he is modifying the sound when he is not. If it makes him feel better then so be it. If he plays better thinking that way then so be it. If a person actually knew music performance they would know that anything that enhances performance, feel, etc is not silly and ineffectual. Don't get me wrong, I think it's always important to learn as much as one can as it can only help(well, almost surely). I'm simply saying that as humans we do not need to understand the details of how something works to take full advantage of it's capabilities. Practice teaches us how things work in "metaphor". With enough playing and awareness one can figure out the true nature of how the mechanism works for piano playing and understand it far better the an any engineer that does not know how to play even without a clue about levers, springs, escapement, etc.

[@austinc1386]

I totally disagree that there is no function for holding a key down after the hammer has already struck. It helps the pianist to maintain the weight and force required to make the next note match. But... You master technicians like to claim that you are master pianists. And vice versa. We should all maintain some humility to accept that we don't understand everything.

[@robertgrijalva7158]

I think you misunderstood me. I did not say that holding the key down is not something a pianist might wish to do, merely that wiggling one’s fingers as if to affect a vibrato on the depressed key is not in any way going to affect the tone of the note. On your other comment about master technicians, et al, I don’t generally mention that I have two degrees in piano performance (Oberlin ‘79 and UW-Madison ‘81), and completed 30 hours toward a DMA before I changed direction toward piano technology. I’ve dedicated my 40 years as a piano technician to bridging the gap in communication between pianists and the piano technicians on whom they rely. This was my mission as Asst. Professor of Piano Technology at the University of Michigan School of Music, Theatre & Dance. I submit to you, with humility, that I understand extremely well how a piano action works.

[@austinc1386]

@@robertgrijalva7158 You are now gravitating toward the claim that you are only talking about vibrato. The fact is, pianists NEED to change the weight/force applied to a note EVEN AFTER THE KEY HAS BEEN DEPRESSED in order to accurately and smoothly crescendo or decrescendo to the next note in a manner and timing that creates a smooth transition. An inexperienced pianist will create a crescendo effect by resetting their applied force between each note. An experienced pianist will increase the force while holding down the key, so that a smooth crescendo effect can be achieved. Keep an open mind. I like this quote: "Don't believe everything you think." We should all keep this wisdom in mind before claiming to be super-smart.

[@P.Robert-m8r]

You clearly are are an inexperienced pianist on top of being arrogant . Any professional pianist understand to maintain the key depressed when you want the damper to be raised as this is the only thing that could happen once the hammer has hit the key . Trying to maintain the force is to be avoided at all cost given you wasting energy for nothing and any serious pianist knows that it’s precisely at that moment that can release the tension . In a nutshell , applying force at the bottom of the key after the hammer has done its job is as silly as trying to vibrate the key literally .

[@robertknox1991]

@@austinc1386 “the claim that you are only talking about vibrato” …… I think you should re-listen to that part of the video again. He says exactly that he is talking about the desire to add vibrato by wiggling a finger on the depressed key. I’m not sure why you are having difficulty hearing and remembering his exact words and then claiming he said something else. After all, you can re-play the video all you want to get the details down if you need to instead of twisting things to make your own unrelated claim.

[@OE1FEU]

@Austin C You have no idea about what you are really talking about when it comes to creating a sound in a mechanical instrument such as a grand piano.