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 keys be spaced a little further apart, while also reducing the jump between black key clusters.
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.
Good point about the ~1mm difference. Interestingly on my MIDI keyboard the difference between white key widths is even larger (maybe ~3mm max), showing some variation in style.
By the way your two comments in this discussion had been voted down and hidden (marked [dead]) for some reason. I voted for them to return and I'm happy to see they've now been reinstated.
There is a good [dead] comment reply to my comment here by user sefn where they point out that in fact the spacing is not exactly equal, it varies by about 1mm (and they're correct).
If you've got "showdead" on, you can see it, click the timestamp on it, and click "vouch" if you want to vouch for it to come back. Seems inappropriately killed to me.
They have a second good [dead] comment in this discussion which I've also vouched to return.
This is fascinating! I’ve never played a YC seriously, but I have played several Yamahas and currently play on a Kawai and Baldwin. I’ve often wondered if the Baldwin or Yamaha is laid out slightly differently than the Kawai because I feel like playing broken 4 note chords the fingering can feel off on one piano vs another. It’s a slight stretch but the 4-5 on the second 4 note chord can be uncomfortable on the Kawai and comfortable on the Yamaha. I never play them in the same room, one is at my teachers and one at home.
Very interesting! Is there a spec for this? Or a layout description? Surely something as precise as piano would note this.
Generally speaking fumbling on a piano doesn’t bode well for performance… it’s a little bit like Olympic gymnastics, you only get one chance to stick the landing!
