Pure concords

The piano, modern organ, and other fixed-pitch modern Instruments are tuned to equal temperament, which means that each semitone is rnade an equal interval. In other words, the twelve tones in an octave are equi-distant on a logarithrnic frequency scale, that is. each töne has a frequency that is 1.059 times greater than the preceding frequency. The advantage of this type of tuning is that the instrument may be played in any key.