Tone Scale Ruler - A must for every musician, music student or composer. Find the tones of all scales in all keys and play them. The scale ruler can be slit to every tone to display a desired scale with correct notation. It also helps you understand the building of scales by a visual representation of the scale (the pattern of intervals). Select the desired scale in the menu. Select the desired variation or notation with the arrow-buttons. Slide the ruler so that the yellow dot is under the desired tone. The tones of the scale will be displayed. You can also choose to view the enharmonic scale. Only in the major scale the yellow dot can move to another tone of the scale rather then the first one by changing the church mode, allowing reverse lookup of finalis and key-tone of the church modes and hypo-church modes. Listen to any scale, ascending or descending, with the build in piano-module.