The Shofar is blown on Rosh Hashanah, the Jewish New Year. There are three different types of noises that are sounded. The first sound is called “Tekiah” and is a bass sound- a long, continuous burst. The second is called “Shevarim” and is made up of three shorter sounds. The third, “Teruah”, is a treble sound and is a set of nine short sounds. The three sounds represent different things. The first is blown in honor of G-d’s Kinship. The second serves as a remembrance of the “Akeida” where Isaac was almost offered up before G-d. The third is purely in order to fulfill the precept of sounding the Shofar.
A beautiful explanation of the different sounds of the Shofar is brought by Rabbi Yehudah Prero at http://www.torah.org/learning/yomtov/roshhashanah/vol3no16.html#. There he begins with the Gemara’s likening of the Shevarim and Teruah sounds to crying. The Ben Ish Chai is of the opinion that these sounds are supposed to contrast with the first sound, the Tekiah. The Tekiah, according to the Ben Ish Chai, is actually a sound of triumphant joy, as opposed to the Shevarim and Teruah sounds that are sounds of suffering. Due to the opposites that these sounds represent, the one blowing the Shofar must be careful that the Tekiah does not run in to the other sounds by making sure not to blow them in the same breath.
The Ben Ish Chai then answers the question of why both the sounds of joy and sorrow are sounded with the Shofar through a story. There was once a man who had a ring made especially for him. It was engraved with the words, “This, too, will pass”, or in Hebrew, “גם זו לטובה”. In times of pain and suffering he would gaze at the ring and be reassured that this state he is in at the moment is only temporary. Also in times of great joy and happiness he would look at the ring. This caused him to be reminded that these good times could change in an instant. These thoughts kept the man humble as he realized that things in this world are beyond his control. This ring was responsible for keeping this man aware at all times of the importance of living with perspective, not allowing complacency not despondency.
The first sound, the Tekiah, is a happy sound. It is immediately followed by the Shevarim and Teruah, broken-hearted sounds of suffering. The sharp contrast is meant to rouse the listeners, to remind them that G-d cannot be forgotten in times of goodness or in times of suffering. Immediately following these sounds a Tekiah is blown again. This symbolizes G-d’s constant presence in our lives and in the world and His mercy that will allow us to merit once again a jubilant existence.