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Piano Keys

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Re: Piano Keys

#41

Post by ofalkaed »

moefh wrote: post #37
ofalkaed wrote: post #36

Earlier quoted context omitted.

Try the wikipedia pages for Equal Temperament and Musical Temperament, they explain all of this. Here is a 1688 Stradivari[1] guitar with fixed frets and a EDO octave, they were reasonably common by that point. Much of the information regarding this is looking at the fixed frets that many lutes and guitars had applied to their soundboard and comparing that to how composers used those fixed frets, either the tied fret…

> I will post it if I remember/find it If you remember and have the time, please do! (And thank you for the links you already posted). I see now that everything I read about this was way too focused on keyboard and violin, since I had never heard any of this about fretted instruments. I'm glad I get to correct a bit of my understanding, so thank you. Now I'm left wondering about wind instruments.

Western theory is focused on the keyboard with violin as second fiddle, the rest of the instruments do their own thing unless they are forced to kowtow to a piano or violin. Each instrument is ultimately tuned to the physics which dictate how it makes sound and this is part of why our tempered 12TET works and why we see the rise of the big orchestras of unlike instruments with the move away from meantone, it provides a compromise which works quite well for all instruments with the exception of the brass (with the exception of the trombone) who are forever out of tune (sort of).

Part of the reason beginners sound bad is because most instruments have to bend notes to be "in tune," I can teach anyone to play a chord on the guitar and get them having each note sounding clearly in a couple of minutes but my DMaj will sound better than theirs simply because I have played that DMaj thousands of times and my fingers have learned to adjust the pressure on each string in just the right way to make it sound "right" just as the woodwinds learn to bend certain notes and the brass learns to live with being out of tune.

Also part of why the lute became such a dominant instrument is that it could retune in ways other instruments can not, which was a major advantage for the working musician back in the days when every city had its own idea about tuning; nudge a few frets, retune a few strings and accept that certain notes were now out of bounds and you could play with anyone like you were playing in your native tongue. As tuning became more standard the lute started to die.

Meantone Temperaments on Lutes and Viols might be of interest to you, it is aimed towards lutenists and violists but has some more general stuff as well and I think does a good job of showing the compromises the lute (and viol) had to make in moving away from equal temperament.

I don't really think brass is forever out of tune, I love the brass and used to play trumpet but the brass section is more under the influence of the physics of its instrument than anyone but the pianist but the pianist is "in tune" because western theory is built around the keyboard.

Re: Piano Keys

#42

Post by yongjik »

ajuc wrote: post #4

I never understood why the piano keyboard isn't regular. It forces players to remember different positions for the same chord transposed to start at different notes. Like why do I have to remember the shape for C major and D major chords? It should be the same shape just starting at C vs D. It's not even that hard to fix. There's 12 semitones in an octave. Just make it 6 white 6 black keys.

That's a bit like complaining that there are six different kinds of chess pieces and you have to memorize how each moves. The truth is, if you have trouble remembering how a knight moves, you can't be that good at Chess anyway.

Remembering twelve different ways of playing a scale is a vastly small part of learning how to play a piano.

Re: Piano Keys

#43

Post by scarecrw »

prmph wrote: post #38

I guess I must be dumb or something, but I'm simply not seeing the problem. Imagine the piano had only white keys, no problem right? Now just place the black keys at the back, between some of the white keys, right in the middle, such that each black key takes like a quarter of the width of the sandwiching white keys. Now what's the problem with this again? Can someone explain in clearer terms? If the issue is that we…

Yes, you do need to press white keys further back sometimes. Imagine trying to play on black keys with your thumb and pinky finger while playing a white key with your middle finger. You won't be pressing all the way at the back, but your finger will have to press between the black keys.

Re: Piano Keys

#44

Post by sefn »

Nition wrote: post #30
madaxe_again wrote: post #23

Earlier quoted context omitted.

In my experience, you fumble for a minute and then you adapt. I had a Young Chang that followed this model, and a Yamaha at school that didn’t.

Interesting, my piano is a Yamaha (specifically a 1980 Yamaha YUA, basically a U3), and it does follow the model (same width everywhere). Photo: https://i.imgur.com/ulsLUoG.jpeg I also have a MIDI keyboard (M-Audio Hammer 88) which follows the same model. I'd like to see a photo of someone's piano that uses a different system, really I thought they were always this way. It's a good system because it lets the black ke…

As the article says, it is impossible to make the back ends of the white keys equal in width so piano makers have to compromise. The difference is about a millimetre so many pianists may never have noticed.

The naive approach of placing each black key at the midpoint of its adjacent white keys makes B, C, E and F quite wide at the base, but it is harder to fit a finger between the black keys to play D, G or A, which can be necessary when the hand has to stretch or play both black and white keys. On a real piano, therefore, the C# and D# keys and the F# and A# keys are offset a little from the midpoints of their adjacent white keys. G# is the only black key that is actually at the midpoint of its adjacent white keys.

In the photograph of the Yamaha piano, you can see that the cutouts on the D key are symmetrical but less than half the width of a black key because the C# and D# keys are offset. Looking at the G key, the right cutout, at half the width of a black key, is deeper than the cutouts on the D key, so to compensate the left cutout is less deep than the cutouts on the D key. As a consequence, the cutout on the F key is deeper than the cutout on the E key, so the E key is wider at the back than the F key. Similarly, the C key is wider at the back than the B key.

As described in the article, on some keyboards just the C and E keys are wider at the back, with D the same width at the back as F, G, A and B. More often, however, the C# and D# keys are placed a little further out to spread the extra width equally between the C, D and E keys.

Re: Piano Keys

#45

Post by sefn »

prmph wrote: post #38

I guess I must be dumb or something, but I'm simply not seeing the problem. Imagine the piano had only white keys, no problem right? Now just place the black keys at the back, between some of the white keys, right in the middle, such that each black key takes like a quarter of the width of the sandwiching white keys. Now what's the problem with this again? Can someone explain in clearer terms? If the issue is that we…

Pianists sometimes do have to play white keys with their fingers between the black keys. For example, if you want to play E flat major (Eb-G-Bb), you might put your thumb on Eb, your little finger on Bb, and then your middle finger on G, right up the back between the black keys. As the keys are parallel, the width of the white keys at the back is the same as the width all the way down to the front of the black keys. Apart from the need to fit the hand to the keyboard, a piano key is a lever and it gives more resistance further back, which may be useful to the pianist in controlling the attack and dynamics.

If you place the black keys right in the middle, as you suggest, the space between them is too narrow for a finger, while there is wasted space for those white keys that only have one adjacent black key. So piano makers push the C# and D# keys and the F# and A# keys further apart.

The mathematical problem discussed in the article is that there is no way to distribute the space equally between the keys, so various compromises are considered. The "B/12 solution" is practical and widely used. The suggested "optimum arrangement" is amusing to consider but unlikely to be worth the trouble.

Re: Piano Keys

#46

Post by [deleted] »

yongjik wrote: post #42
ajuc wrote: post #4

I never understood why the piano keyboard isn't regular. It forces players to remember different positions for the same chord transposed to start at different notes. Like why do I have to remember the shape for C major and D major chords? It should be the same shape just starting at C vs D. It's not even that hard to fix. There's 12 semitones in an octave. Just make it 6 white 6 black keys.

That's a bit like complaining that there are six different kinds of chess pieces and you have to memorize how each moves. The truth is, if you have trouble remembering how a knight moves, you can't be that good at Chess anyway. Remembering twelve different ways of playing a scale is a vastly small part of learning how to play a piano.

[deleted]

Re: Piano Keys

#47

Post by tgv »

ajuc wrote: post #4

I never understood why the piano keyboard isn't regular. It forces players to remember different positions for the same chord transposed to start at different notes. Like why do I have to remember the shape for C major and D major chords? It should be the same shape just starting at C vs D. It's not even that hard to fix. There's 12 semitones in an octave. Just make it 6 white 6 black keys.

There still would be two "shapes": C vs C#. Transposing would only be easier by two semitones.

But for most music and musicians it isn't that interesting. Transposing is rather niche. If it's too hard, an electronic keyboard can do it for you.

Re: Piano Keys

#48

Post by amingilani »

yongjik wrote: post #42
ajuc wrote: post #4

I never understood why the piano keyboard isn't regular. It forces players to remember different positions for the same chord transposed to start at different notes. Like why do I have to remember the shape for C major and D major chords? It should be the same shape just starting at C vs D. It's not even that hard to fix. There's 12 semitones in an octave. Just make it 6 white 6 black keys.

That's a bit like complaining that there are six different kinds of chess pieces and you have to memorize how each moves. The truth is, if you have trouble remembering how a knight moves, you can't be that good at Chess anyway. Remembering twelve different ways of playing a scale is a vastly small part of learning how to play a piano.

> if you have trouble remembering how a knight moves, you can't be that good at Chess anyway.

Non sequitur.

It’s also still a valid question. I play the scales really well on the guitar. And because the frets are all laid out straight, shifting up by one fret means I’m just playing my chords and scales sharp. It makes transposing music incredibly easy.

I still don’t understand why the piano can’t be laid out like that.

Re: Piano Keys

#49

Post by brudgers »

prmph wrote: post #38

I guess I must be dumb or something, but I'm simply not seeing the problem. Imagine the piano had only white keys, no problem right? Now just place the black keys at the back, between some of the white keys, right in the middle, such that each black key takes like a quarter of the width of the sandwiching white keys. Now what's the problem with this again? Can someone explain in clearer terms? If the issue is that we…

Pianists don't press the white keys all the way at the back, do they?

The good ones do it all the time because moving the entire hand forward and back can be significantly more fluid than contorting to play another way…the keyboard is three dimensional.

Re: Piano Keys

#50

Post by drabbiticus »

Nition wrote: post #31
ajuc wrote: post #4

I never understood why the piano keyboard isn't regular. It forces players to remember different positions for the same chord transposed to start at different notes. Like why do I have to remember the shape for C major and D major chords? It should be the same shape just starting at C vs D. It's not even that hard to fix. There's 12 semitones in an octave. Just make it 6 white 6 black keys.

With the irregular layout we have now, some keys are easy (e.g. C) and some are hard (e.g. B). If you make the layout regular, putting a black note between every white note, then every key becomes the same, but also quite hard, because every major scale is now played like this: https://i.imgur.com/6EmW8eU.gif It's not a particularly good tradeoff. If you got rid of the black keys entirely instead, you'd have to remem…

That regular layout also makes it likely to feel better to the hand to play diminished or augmented chords, while comparatively punishing major/minor chords. It would be an odd choice considering the traditions of western music.

There's also something to be said about each key having a specific motor pattern/spatial layout. Sure, it makes it harder to move knowledge of one key into another, but during playing it also makes it easier to not accidentally completely change the key unless you mean to. It's all tradeoffs.

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