By moving the tuning key (in the tuning peg!) towards you (right arrow), the string is less stretched, and the note is lower.

By moving the tuning key towards the front of the harp (left arrow), the string is more stretched, and the note is sharper.

The tuning device shows if tne note is true, neither too sharp or too low. The right button on the right-hand side (click on the picture!) shows the frequency band of the standard pitch (that is to say the A); I tune my harp at 440 or 441 Hz. The top bar shows the played note. The central pointer must be on 0, and the two neon arrows (on the left and right-hand sides) must be lit to get the string in tune.

If your harp is amplifyed, you can tune it even in a noisy room, by using the jack to plug into the tuning device (check course n° 4)