Keystroke Velocity

[iroveashe]

I was thinking about the factors that affect the sound tone and quality on a single note: the weight and strength you put into the keys and the velocity of the fingers pressing them down. Since I can't play right now, and my piano is not good enough to test this in the most effective way, just thinking I came to the conclusion that both of those aspects should be controlled in order to gain not only different volumes, but different texture. Later on I found this video which basically confirms that. However, in Chang's book I read the opposite (in this section and the next), that the key should be always struck at high speed, while the tone quality of a single note depends on other factors. Is one of the approaches right and the other wrong? Are they simply 2 valid but different ways? Or am I missing something?

[go12_3]

*delete*    I didn't make the correct reply here.  Sorry!   

[iroveashe]

I'm not talking about pieces, I'm mostly asking about the part relating the keys, hammers and strings and all the mechanism in between. So I'm not talking about fingers, wrists or any part of the body either; they are factors of course but what our bodies do to press the keys is not relevant to the subject, it's what happens after that. Also I'm talking about a single note, so staccato or legato is not relevant either.

[allthumbs]

I was thinking about the factors that affect the sound tone and quality on a single note: the weight and strength you put into the keys and the velocity of the fingers pressing them down.

It is quite simple. Force = Mass X Acceleration

It makes no difference to the piano or the sound it produces if the resulting keystroke produced by a concert pianist or non-player striking the key has the same acceleration and weight.

Once the keystroke is initiated and the key strikes the string, the keystriker can do nothing to alter the resulting sound. It will sound the same in both instances between the concert pianist and the non-player when the above equation is balanced.

What does make the difference is the pianist's ability to change the force subtly from note to note and alter the timing slightly between notes.

[iroveashe]

What I'm trying to find out is if you play the same note twice at the same exact volume yet one time moving the key down fast and the other time slow, will the exact same sound be produced (theoretically speaking)?

It is quite simple. Force = Mass X Acceleration

It makes no difference to the piano or the sound it produces if the resulting keystroke produced by a concert pianist or non-player striking the key has the same acceleration and weight.

Once the keystroke is initiated and the key strikes the string, the keystriker can do nothing to alter the resulting sound. It will sound the same in both instances between the concert pianist and the non-player when the above equation is balanced.

By that answer I'd say it's a yes, the sound will be the same as long as the mass and acceleration result in the same force to produce the same volume, right? So what Golandsky said in the video is false?

[allthumbs]

What I'm trying to find out is if you play the same note twice at the same exact volume yet one time moving the key down fast and the other time slow, will the exact same sound be produced (theoretically speaking)?

You cannot move the key slow one time and fast another time and produce the same sound without having the mass of the key changing, which is impossible.

By that answer I'd say it's a yes, the sound will be the same as long as the mass and acceleration result in the same force to produce the same volume, right? So what Golandsky said in the video is false?

Looking at the original equation F = M x A and rearranging it to M = F / A
where M is a constant (weight of the key/shaft) if one doubles the force applied to the key, the resulting acceleration will also double producing double the force of the hammer hitting the string.

[richard black]

What I'm trying to find out is if you play the same note twice at the same exact volume yet one time moving the key down fast and the other time slow, will the exact same sound be produced (theoretically speaking)?

The volume of the note depends only on the velocity of the hammer, which in turn depends only on the velocity of the key, so your question strictly doesn't make sense.

In basic terms, you only have one parameter for a given note - its loudness or volume. You can't really vary the tone of that note. If one wants to invoke subtleties and second-order effects, you should consider the extraneous noises, which are basically the finger striking the top of the key and the key striking the key bed. You can't do much about the latter, realistically, but you can reduce the former by keeping fingers close to the keys at all times.

But as I said, that is second-order. What's far more important in normal playing is the relative loudness of notes within a chord, and of notes close to each other in time, and also the precise timing of notes ditto. That's where 'pianist tone' comes in.

And by the way, I hate to pull rank and all that but I should point out (before someone weighs in and flatly denies what I've just written) that I am a degree-qualified physicist and an experienced audio engineer as well as being a pianist, so I feel I do have some sort of handle on the subject!

[lostinidlewonder]

Considering a single note?? This is not music, this belongs in a science room if you want to measure forces. It is like studying poetry and not considering a single word (which would be ridiculous to start out with) but a single letter (which is even more mad!) in the stanza! However what results you get will not help you with your musical journey.

I was thinking about the factors that affect the sound tone and quality on a single note

Can a single note actually have a tone and quality without being related to a phrase of music? A single note can be stacatto, legato or many different forms of accents ( _ , >, ^ etc) each produced with various movements of our hand but I think it is going to far to say a single note has a tone, rather a single note can have a quality. Tone is something we define by observing how a phrase of music is expressed and how the notes interact with with one another.

I came to the conclusion that both of those aspects (wieght and strength) should be controlled in order to gain not only different volumes, but different texture.

If we want different sounds and textures we must relate it to a phrase of music. It is silly to look at a single note and work from there. It would be like building a car and starting with the ashtray. We must consider the phrase of muisic, understand how all elements are working together with one another in our minds eye, then translate this imagination to our hands.

The difference when considering a group of notes than to a single note is that they all interact with one another. You must make decision with all the notes and how they fit in with one another. Where in Bach you may get away with playing everything evenly and support what is in most danger to fail in tone rather that giving bais to one voice or the other, something like Chopin we may have to draw out the melody and gently support it with the other notes but allow deep basses to draw through like bells.
 The only way we can find this out if by playing a phrase of music, considering the single note will not yield anything interesting because it is disconnected from the phrase of music.

[iroveashe]

Considering a single note?? This is not music, this belongs in a science room if you want to measure forces. It is like studying poetry and not considering a single word (which would be ridiculous to start out with) but a single letter (which is even more mad!) in the stanza! However what results you get will not help you with your musical journey.

It was just a question because I was curious. Should I not have asked it and stay with the doubt because you think it's silly? You can change the sound on a single note by playing it different ways in for example, a guitar and when I say single note I don't mean out of context. Let's say you have a guitar piece and you have a musical phrase with repeated notes but you want to give accent to a note without it being too much; you could hit the string with a different part of the thumb/pick, or play in different parts of the string: you'd be changing the sound without changing the volume. I was just wondering if something similar could be done at the piano, and when I saw the video, unless I got it wrong, that's exactly what Golandsky said.

If we want different sounds and textures we must relate it to a phrase of music. It is silly to look at a single note and work from there. It would be like building a car and starting with the ashtray.

I don't see how you came to the conclusion that I looked at a single note and worked from there. If a car designer was finishing a sketch and suddenly realized he forgot to include the ashtray, would it be silly if he started asking questions about them?

But anyways, thanks to Richard Black and Althumbs for clearing that up.

[go12_3]

What I'm trying to find out is if you play the same note twice at the same exact volume yet one time moving the key down fast and the other time slow, will the exact same sound be produced (theoretically speaking)?

I have been reading through this thread and it seems to me that no two sounds can't be *exact* because of the human touch of the fingers, by pressing and releasing the key.  The human touch is not like a machine in which would strike the key exactly all the time.  Now, think about sound waves, here, when you strike a key twice one fast and then one slow, the sounds waves would differ and our ears would detect the differences.  I think so.  

It depends upon the key action of the piano also.  When striking a key down quickly would produce a sharper or staccato sound and when striking the key slower would be a softer sound or tone.  Each piano has their own sound and the fingers is what will produce that sound.

best wishes,

go12_3

[iroveashe]

I have been reading through this thread and it seems to me that no two sounds can't be *exact* because of the human touch of the fingers, by pressing and releasing the key.  The human touch is not like a machine in which would strike the key exactly all the time.

Of course, that's why I said theoretically speaking.

[lostinidlewonder]

Should I not have asked it and stay with the doubt because you think it's silly?

I don't think it is silly, no questions are silly. I just cannot see the musical application of thinking of a single note out of context to the other notes of a phrase, maybe there is something?

...Let's say you have a guitar piece and you have a musical phrase with repeated notes but you want to give accent to a note without it being too much; you could hit the string with a different part of the thumb/pick, or play in different parts of the string: you'd be changing the sound without changing the volume. I was just wondering if something similar could be done at the piano.

Do you mean repeated note pulses with an accent on certain notes to create a rhythmic quality? This is no longer one sole struck key, but a group composed of a single note with a rhythmic quality produced through accent. But you still have to play a number of the same notes to produce this, not just a single note on its own.

I don't see how you came to the conclusion that I looked at a single note and worked from there. If a car designer was finishing a sketch and suddenly realized he forgot to include the ashtray, would it be silly if he started asking questions about them?

I don't know what you do personally yourself, I treated your question as merely a question, a thought. Not something that defines your method. I was just wondering how can considering a single note aid us? I find it is a trap trying to think in too many small steps at a time, and considering single notes in my opinoin, is probably the slowest way to possibly work or discover things about your music.

When we consider a single note in isolation to the phrase of music we will start doing things differently. We will play the single note in context to itself and not the phrase. This is why considering single notes at a time does not yeild interesting results, because as you introduce the other notes how you played that single note may indeed change.

[iroveashe]

Do you mean repeated note pulses with an accent on certain notes to create a rhythmic quality? This is no longer one note but a group composed of a single note with a rhythmic quality produced through accent. But you still have to play a number of the same notes to produce this, not just a single note on its own.

Not rhythmic accent. Say you have 4 A's and you play the first 3 near the bottom of the guitar with a pick, it will have a bright and sharp sound; now you play the last note near the neck of the string in such a way that it has the same volume as the notes before, it will sound different. Now take just the last 2 notes of that group, you will have the same note in 2 different moments of time, with the same volume yet different texture, color or whatever you want to call it.

I was just wondering how can considering a single note aid us? I find it is a trap trying to think in too many small steps at a time, and considering single notes in my opinion, is probably the slowest way to possibly work or discover things about your music.

Imagine as if I'd have asked if it's possible to do a crescendo on one note (and ignore the fact that the answer is completely obvious). I already know that it is possible to do a crescendo on a series of notes progressing in time, so the other notes are not relevant to the subject (which of course does not mean those notes are musically irrelevant!). Because I'm asking about how a single note can be altered doesn't mean I'll take one piece and go note by note trying to do a crescendo in each of them. If I know it's not possible I wouldn't try of course, but if it was I'd simply have one more tool to use whenever I want. On a single note, a crescendo sounds as illogical to any of us as changing tone without changing volume must sound lo Althumbs, but to me, the later isn't obvious.

[theodore]

Because the piano hammer is the only practical way a single note can be produced, tonal results are extremely limited. Other instruments (strings, brass woodwinds ) have much more extensive tonal result variations for single notes such as: vibrato, crescendo, ponticello, pizzicato, harmonics, fluttertone, swelling and diminution  < >  ,  plus a whole variety of dynamic effects such as  sfp and  fp etc…

The piano then must rely on a series of notes for any variation to occur.

 

[brucem]

This all depends on the timing relationship between the first note and the second.

After playing the note once, are you fulling releasing the key? Or are you releasing just enough to re-engage the escapement, allowing the note to be repeated. In these two cases, the keystroke distance differs, as does the hammer's travel distance (more so on an upright than on a grand).

Also ... after playing the note once, are you waiting for the sound to decay before playing the note once again? Or are you repeating the note immediately, thereby interrupting the first strike's decay with a fresh strike?

(The F=MA analysis is incomplete, because it considers only the keystroke, and does not account for the activity behind the fallboard.)

[tengstrand]

As some have pointed out, the sound is produced when the hammer hit the strings, and since:

1) the hammer's last bit of going up is free and cannot be altered once the motion is set

2) we cannot strike the key in a way for the hammer to move sideways

the only thing that counts for sound production of a single note is the speed of the hammer.

You cannot alter the sound with the exact amount of dB in a note.

If the speed of the hammer is exactly the same, it does not matter if it's Rubenstein, a monkey or Dick Cheney who played the note. It will sound exactly the same.

That said, achieving a good sound has everything to do with how one "hits" ( anyone has a better word?) the keys. I have enjoyed a hundred times the magic of playing forte with a slow touch, and piano with a quick touch.

Gotta love piano playing...