The Only Thing They've Done Wrong

The dampers in a piano run from the first note up to about the 68th note, the E two octaves above middle C, which is called E6.  After that, there really is no need for dampers because the strings don't ring out for very long.  Some pianos run dampers 5 or 6 notes above E6, but most piano manufacturers avoid the extra cost and stop at E6 (or try to cut it a bit short one or two notes).

Most of the time you don't notice where the dampers leave off, but a sensitive player will always notice.  Sometimes it can be annoying, because the notes just after the last damper can't really be played staccato, and the transition from damper to no-damper is abrupt both for the hand and for the ear.

In an attempt to ameliorate this abrupt transition, Yamaha uses a partial damper felt on its last damper, E6.  The idea is that D#6 damps fully, E6 damps partially, and F6 damps not at all - voilà, a smooth transition!  Except not really.  It's a nice idea, and probably a nice marketing point, but listen carefully to the transition, and you might hear what I'm hearing as the notes die out.

The sound in a piano comes from hammers hitting strings.  As soon as a string is struck, it vibrates and transmits most of its energy ultimately to the soundboard, thence to the air as sound waves.  As the string gives up its energy, the volume of the sound decreases, a process called decay.  Decay begins immediately after the string is struck, and is rapid at first, but then the decay rate drops quickly.  In a good piano, the decay rate slows significantly; the string can ring out, at a moderate yet still decreasing volume, for a long time.

Here's my beef with Yamaha's partial damper.  D#6, E6, and F6 all have a similar decay, as one would hope.  D#6 can also have its sound damped, and F6 cannot.  But when you damp E6, only two of the three strings are damped.  The third string rings out, but it decays at a significantly different rate than F6.  Instead of hearing a smooth transition, I actually hear two different transitions; the one from D#6 to E6, and the one from E6 to F6.  Call me sensitive, but it drives me crazy; I'd rather have the one abrupt transition.

The reason the decay is different, by the way, is because a single string transfers energy to the soundboard differently than three strings vibrating in phase.  Of course, the difference is greater in the early part of the decay.  Towards the end of the decay, the difference is negligible to none.  But if you're relying on the damper to do its job, you usually want to apply it in the early part of the decay.

Well, if this is all Yamaha has done wrong, they're doing OK.  But I've noticed a growing number of manufacturers mimicking Yamaha's partial damper, and it can't be because it works so well.