It contains originals (notated songs with lyrics and notated instrumental tunes), transcriptions, descriptions, copies and decodes from phonic recordings. The data, stored on hard copy, consists of 10 000 inventory items in 250 000 leaves. This archive dated its beginning from the end of 19th century and was collected by a number of prominent folklorists: Angel Boukoreshtliev, Konstantin Zagorov, Pavel Stefanov, Vassil Stoin, Rayna Kazarova, and others. The most part of archive has not been published. Its timely transformation on modern technical bearers would preserve it for next generations.
It contains 5 000 tapes, including valuable folk recordings, some of them representing artefacts of unique events. This is the only archive in the country, which preserves sound materials from the Thracian folk area down the valley of Maritza River, collected by the folklorist Vassil Stoin. The archive contains as well around 800 numbers of wax, glass and metal based records, and audiocassettes. In addition, the archive contains over one thousand of vinyl records from the 1920s through the 1970s, published by the record labels Pathé, Orphey, Odeon, Polidor, Zenith, Simonavia, Microphone, Favorite, Radioprom, Balkanton, and others. They feature opera, folk, shlager, march and other sorts of music.
It contains around 100 000 frames, dating from the middle of the previous century up to present days. They have index of contact prints. The photo archive has documented exhibitions, vernacular festivities, dance folklore objects, instrumental players, ritual folklore. It contains as well photo documentation of antique objects of art, sculptures, mosaic and mural paintings, medieval churches and monasteries, some of them already ruined. Churches and monasteries from the time of Bulgarian National Revival, icons, wood iconostasis, church ritual objects, samples, interior wood and mural decoration of the 19th century houses are documented as well. Exhibitions from the 1960s through the present days and particular works of Bulgarian artists from different generations are photographed as well. Some of these paintings are part of private collections and they are not accessible for general public. Others are damaged or lost, thus, the archive has the only evidence of their existence.
It contains videocassettes featuring all Koprivshtiza folk festivals and recordings of Bulgarian ritual and dance folklore.
It contains more than 800 black-and-white and colour films from field expeditions, recorded mostly on 16-mm film.