Robab: Robab is one of the oldest stringed instruments in Iran. It is made of wood, leather, string or nylon thread. It is popular in the eastern and southern parts of the country. It is also common in neighboring countries. Today, due to the lack of bass instruments in Iranian music, Robab has a more prominent presence. Robab History: Robab is a native instrument of the eastern provinces of Iran, especially Sistan and Baluchestan. It is also popular in neighboring countries. In the 1930s and 1940s, Robab was used in Iranian national instruments. It can be said that Robab is one of the oldest instruments in Iran, and there are pictures of this instrument in the engravings and carvings of old dishes. Mohammad Nasim Khoshnavaz, an Afghan musician and music teacher, said about Robab: "Some Iranian instruments are rooted in Khorasan and have been forgotten today, but Afghan musicians consider this instrument to be their companion. The footprints of this instrument can also be found in the verses of Hafez and Rumi: Robab which is used in group playing today, is made of walnut, berry and hardwoods. Over the centuries, the structure of this instrument has undergone changes. In some areas, the Robab is held vertically like a fiddle, with the help of a bow. In the group playing of city centers, the robe is placed horizontally on the knee like a lute and it is played by the mallet. instumentology: Robab is classified as a stringed percussion instrument. It is made of a hard wood such as mulberry or walnut. Robab components include: bowls, chests, handles, claws, and other smaller components, all of which are integrated. The number of strings are 6 or 3 pairs. Robab instrument components: The resonant bowl consists of two parts, the bowl and the chest. The bowl is empty and larger, with the skin at the opening. On the sides of the bowl, there are two hollow that are located on the side of the bowl, and it looks like the bowl is two-part. In making some Robabs, these two hollows are created a little higher, between the bowl and the chest.

Chest: The chest is a triangular and hollow box the approximate size of the bowl section, which is located along with the width of the bowl at the junction of the bowl and on the claws from the other side. The surface of the chest is covered with a thinly cut wooden plate. In the urban type, because the vocal chords are not used, the small earphones on the side surface look decorative, and the holes created for the chords to pass through are open due to better sound output from the reverberation box. It also has two groups of earphones:

1. earphones related to the main strings in the claw

2. earphones for vocal strings on the bowl

handle: The handle is a short ribbon and a continuation of the wooden part of the chest, which eventually reaches the claws as a pyramid. The four frets are tied on the handle, and often bone ornaments are placed on the handle.

claws: they are like a small empty box is located at the beginning of the handle length at the location of the head of the main chords and earphones. The claw is tilted back slightly; On all three sides, there are six earphones with the same number of chords. If decorative shapes and forms are used at the end of the claw head, it is called sarahi. Skin: Because Robab uses thick chords with short handles, which puts a lot of pressure on the skin. So, the stretched skin covers the bowl and is usually thicker than similar instruments. valut: A piece of horn or wood with an approximate length of 6 cm, which is placed on the skin by its two small bases. The chords pass through its shallow grooves. To make the instrument sound better, the plectrum should be placed a little farther from the vault, close to the chest, on the chords. pallet: A thin, low-heeled piece of bone along with the width of the handle, which is located between the handle and the claws, and the chords pass through its shallow grooves to close the earpieces. Tailpiece: A small piece of metal at the end of the body of the bowl to which the chords are tied. Chords : Robab has 6 main chords that are tuned in pairs. Today, guitar strings are used for Robab, but in the past, gut or silk thread was used. Width: Usually the range of Robab's usual sound is one and a half octaves. Changes in the Robab instrument: Master Ebrahim Ghanbari Mehr created a correction set by installing a grip, placing a metal curtain, reducing the width and thickness in order to increase the volume and facilitate playing. Other composers decided that due to the needs of the musician make some corrections and changes in order to achieve a sound with a higher quality and closer to the original sound and easier playing, which are:

1. Robab is basically a bass instrument, so in order to make a high volume, they installed a network between the grip and the skin. 2- The grip extended to the initial part of the skin and the network was transferred to both sides. In this design, the sound level of the melody with 3 melodic strings (main string) is approximately 2.5 octaves, and in melodies with 4 melodic strings, it is approximately 3 octaves, in this case the range of the instrument's sound is increased. 3 - Reduce the length of the Robab bowl (the part on which the vocals are installed) and add the same length to the handle length. In this case, 7 earphone and vocals are installed on the bowl; Therefore, in order to reach 13 earphones and vocals in the size of Alto and 15 earphones and vocals in Shah Robab (bass size), the earphones were installed in two rows. 4 - For ease of playing, a wooden piece with a special form was installed at the contact point of the musician's forearm with the edge of the bowl. Robab musicians: Bijan Kamkar Hossein Alizadeh Mohammad Rahim Khoshnavaz Manufacturers of Robab: Professor Hossein Ghalami Ebrahim Ghanbari Mehr