When performing in the Eurovision Song Contest, all artists use in-ears, a sort of earphones providing them the sound to stay in tune.
This hasn't always been the case. In the old days, artists had to use only their own ears to manage.
Dino Merlin from Bosnia & Herzegovina is capable of using both methods. For the Second Semi-Final on Thursday, when he qualified for tonight's Grand Final, he only had one in-ear device for his performance of the song Love In Rewind. This almost proved fatal.
"I was afraid. Just when I started to sing, the audience started to clap, and I only had one in-ear. It was so hard to stay in the beat," Dino says to Eurovision.tv.
Dino recognises the great atmosphere in Düsseldorf Arena as a compliment to him. But the live broadcast of the Semi-Final was the first time that he and the other artists got to perform in front of a big audience in the arena. The rehearsals haven't been as well attended in the huge stadium.
"Luckily, I'm used to stay in rhythm. I couldn't imagine that the audience would start to give me rhythm all the song! It's a very difficult situation when you have a rhythm with a little bit delay," Dino explains.
For the Final tonight, he will be using two in-ears.