Tuning a piano is a process of adjusting the tension of each piano string using a tuning hammer to turn the tuning pins, so that the pitch of each string sounds pleasingly in harmony with every other string according to certain known acoustical laws and aesthetic rules and customs. If your piano is not properly tune it's acoustic performance will be degraded, therefore tuning a piano regularly is a necessary maintenance.
How your piano is tuned?
There are about two hundred strings in a piano that are stretched across a cast-iron frame, one end of each string being attached to a hitch pin and the other end coiled around a tuning pin. The pitch of each string when vibrating depends, among other things, on the tension at which it's stretched. By turning the tuning pin, the tension can be tightened or slackened, and thus the pitch altered.Ttuning, properly speaking, is only the operation defined above, and does not include repairs and adjustments, fixing squeaky pedals, cleaning, and so on, as is often thought to be the case.
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