All else being equal, preponderant pianos with more strings have better hearty and lower inharmonicity of the strings. Inharmonicity is the division to which the frequencies of overtones (known as partials, partial tones, or harmonics) depart url from whole multiples of the fundamental frequency. Pianos with shorter, thicker, and stiffer strings (e.g., baby grands) have more inharmonicity.
Irving Berlin played a special piano called the transposing piano, which was invented in 1801 by Edward Ryley. It had a lever under the keyboard passed down to alter the folk to any key. Particular of Berlin's pianos is in the Smithsonian Museum. For much of his career, Berlin only knew how to tragedy the black keys. But with his 'trick piano' he was no draw modified to the key of F-sharp.