Characteristics
Toy pianos come in many shapes, from scale models of upright or grand pianos to toys which only resemble pianos in that they possess keys. Toy pianos are usually no more than 50 cm in width, and made out of wood or plastic. The first toy pianos were made in the mid-19th century and were typically uprights, although many toy pianos made today are models of grands. Rather than hammers hitting strings as on a standard piano, the toy piano sounds by way of hammers hitting metal bars or rods which are fixed at one end. The hammers are connected to the keys by a mechanism similar to that which drives keyboard glockenspiels. Some new toy pianos are electronic.
Toy pianos ostensibly use the same musical scale as full size pianos, although their tuning in all but the most expensive models is usually very approximate. Similarly, the pitch to which they are tuned is rarely close to the standard of 440 Hz for the A above middle C. A typical toy piano will have a range of one to three octaves. The cheapest models may not have black keys, or the black keys may be painted on. This means they can play the diatonic scale (or an approximately tuned version of it), but not the chromatic scale. Typically, diatonic toy pianos have only eight keys and can play one octave. Other variants may have non-functioning black keys between every key (which would make it appear to play the quarter tones between E/F and B/C), but they either do not play, play the same notes as an adjacent white key, or play a special sound effect.
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