Buying a Grand Piano Less than Five Feet Long
Larry Fine and Volunteer Reviewers
THERE WAS A TIME WHEN, as they say, I wouldn't have wrapped fish in a grand piano under five feet long. The short cases of these pianos place severe constraints on string length and soundboard design, and often result in instruments with poor tone. Given these pianos' lack of musical qualities, most buyers have been understandably more interested in them as pieces of furniture than as musical instruments. To compete at this end of the market, manufacturers have traditionally needed to make and sell such pianos as inexpensively as possible, sometimes skimping on materials until the pianos just barely hold together. The smallest of these instruments made by American manufacturers in the 1980s were referred to derisively by piano technicians as "piano-shaped objects."
Times have changed. While much of the above is still true to some extent, great strides have been made in the intelligent design and construction of small pianos. Piano-scaling software, advances in soundboard design, globalization, and the computerization of manufacturing have all contributed to the ability to produce grand pianos that are compact and inexpensive, yet still fully functional and satisfying to play. This was brought home to me recently when, at a trade show, I heard from some distance a piano that sounded exceptionally lovely. Drawing near to find out what it was, I was amazed to discover that it was only 4' 10" long. I decided it was time to take another look at these instruments. Of course, some are better than others, and some guidance in listening to and choosing one is advisable.
The place to begin is with the strings in the low bass. Normally among the longest in a piano, these copper-wrapped strings must be made thicker than normal to compensate for the length that the piano's small size makes impossible. The extra thickness makes them stiffer, causing the harmonics they produce to deviate from their theoretical frequencies, in a phenomenon known as inharmonicity. (This happens to some extent with all pianos; it's just much worse in small ones.) The problem here is that the fundamental frequency of a bass string is weak in comparison to its harmonics, and the ear "hears" the pitch of the note largely by listening to the harmonics and inferring from them which fundamental would have produced them. When the inharmonicity is extreme, however, each harmonic suggests a different fundamental, thus confusing the ear, which hears an indistinct pitch. So when trying out a small piano, play each note in the bass to see how low you can go before the pitch becomes unclear. (If you can no longer hum the note, the pitch is probably not clear enough to discern.) If this point on the keyboard is well within the normal range of the music you play, the piano may not give you the musical enjoyment you're looking for. Another area to pay attention to is the transition between the tenor and bass; here, the lowest unwrapped treble strings can sometimes give off an indistinct or otherworldly-sounding pitch much different from the wrapped strings just below.
Quite apart from the distinctness of the pitch, the bass tone can be deficient in other ways. Unless carefully designed, the soundboard of a small piano can be much stiffer than that of a larger one due to its smaller surface area, and its vibrations are more easily stifled by careless bridge placement. For the low frequencies of bass notes to be properly produced in a piano, however, greater soundboard flexibility is required, so traditionally there has been a tendency in small pianos for the bass tone to be dull and thumpy, with short sustain. When testing a piano, then, listen for resonance and sustain in the bass notes, and reject instruments that sound stifled and dull.
Modern piano designers are beginning to make progress in mitigating the problems inherent in the very small piano. Ironically, one of the biggest obstacles to this progress comes from the manufacturers' own marketing departments. The dull, thumpy sound of the typical small grand is the inevitable result of several common and widely promoted, but ill-advised, design characteristics, perhaps chief among them the quest for the maximum possible speaking length (string length). While it's true, in a very broad sense, that longer strings give off a better tone due to their lower inharmonicity, among very small pianos, a slightly shorter bass-string speaking length allows the bass bridge to be positioned more optimally on the soundboard, the resulting enhanced resonance and sustain more than making up for the slightly greater inharmonicity. So when the salesperson tries to persuade you that his or her very small piano is better than the competition because of a longer speaking length, politely offer your thanks ... and seek out the competition — it may well be a better-sounding instrument.
Interestingly, regardless of the quality of a small piano's bass, its treble will often sound quite lovely. The reason lies in the fact that the strings in the highest three octaves of any piano are naturally fairly short, and so are relatively unaffected by the piano's size; and because soundboard stiffness, while a detriment to the bass tone, actually enhances the higher frequencies.