CONCERT PITCH

Pitch is the perceived fundamental frequency of a sound. While the actual fundamental frequency can be precisely determined through physical measurement, it may differ from the perceived pitch because of overtones, or partials, in the sound. The human auditory perception system may also have trouble distinguishing frequency differences between notes under certain circumstances. According to ANSI acoustical terminology, it is the auditory attribute of sound according to which sounds can be ordered on a scale from low to high.
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Noun
1. the pitch used to tune instruments for concert performances; usually assigns 440 Hz to the A above middle C
(synonym) philharmonic pitch, international pitch
(hypernym) pitch

The international tuning pitch - For the guitar this is A = 440 oscillations a second. It's amazing how many guitarists refuse to acknowledge that there is such a standard. There is nothing more annoying than to rock up at a rehearsal or performance venue to find that the other guitarist(s) are out of tune for whatever reason. All you can really do sometimes is grit your teeth and whistle, 'Don't worry, be happy'. Attempting to tune your instrument to the non standard pitch while dancers and palmeros are making lots of noise is no fun, especially when you take on the aura of the villain, because you are holding up proceedings while you tune. Life is so unfair.

DIAPASON DA CONCERTO. STATO DI ALL'ERTA

Eng: concert pitch
Urdu: سازینا کا عام دَرجہ سے ذرا زیادہ بُلَند دَرجہ ۔