The Gaida (bagpipe) is one of the most characteristic folk instruments of Bulgaria. It is said that a traditional wedding is incomplete without its presence. Traditionally the solitary shepherd's companion, it is often heard solo or accompanied by a large drum. It is also popular in small village orchestras. Like all Bulgarian folk instruments there are many regional variations with distinctive styles of detail and ornament. All share a common form: white kidskin bag, blowpipe, drone and chanter. The pipes of the eastern regions of Thrace and Dobrudja are usually high-pitched, while those of western Shope region tend to be lower. In the south Bulgarian Rhodope mountain region they are extremely deep-pitched with huge goatskin bags. These are often played in pairs or trios and sometimes in large groups. There is one ensemble in that area called "Sto Gaidi", which translates as "One Hundred Gaidas". The standard instrument today is an outfit consisting of three chanters and two drones, giving the player capacity to perform music of all regions. The chanter, called a "gaidanitsa", makes this instrument unique. It has the capability of a full chromatic scale. Its conical bore may have up to seven subtle changes. The tone holes are curved and recessed to give the fingers a relaxed and comfortable grip. Its most unusual detail is the "flea hole", a small metal pipe or bushing at the top of the bore. This gives the instrument its exceptional chromatic range. The pipes are traditionally richly decorated with delicate grooving or combing and trimmed with metal and ox horn of varying hues. The kaba-gaida of south Bulgaria is a huge instrument. Its single drone is almost four feet long. It has a deep and noble tone. Its gaidanitsa is hexagonal rather than round in cross-section, and it is richly ornamented with subtle carving.
The gadulka is probably the most popular and also most ancient folk instrument in Bulgaria today. Although loud and resonant, its distinctive Slavic voice is warm and soothing. It is traditionally played in small orchestral groups or used to accompany singing. Most folk musicians make their own instruments following strong regional traditions of form and tuning, though there are many renowned professional makers. Two types of gadulkas are commonly played. Both are made from large single blocks of hardwood that are carved and hollowed into pear like corpus, then covered with resonant softwood faces. The more prevalent form has three bowed strings, tuned A'EA with ten to twelve additional sympathetic strings. The other type is much smaller and its playing is restricted to the Dobrudjan region near the Black Sea. It usually has three strings tuned EAA'. Unlike violins, gadulkas are played tucked into a shoulder strap or belt and bowed horizontally. The Tambura is also a popular instrument. It is similar in form to the gadulka, with a curved, pear shaped form. It has a loud, bright tone somewhat like a banjo, and is commonly used for both melody and chords. The strings are double-coursed like a mandolin but are tuned like the upper strings on a guitar.
The kaval, a Bulgarian or Balkan end-blown flute is also a common shepherd's instrument played in orchestras and as an accompaniment to singing. It is universally popular in Bulgaria. Playing techniques vary throughout the country. Typically a staccato style is played in the West, while a richly ornamented style is played in the East.