Soviet (and then Belarusian) vocal-instrumental ensemble. Founded in September 1th, 1969. Previously it was a variety revue Лявониха with inner ensemble Лявоны. But in 1970 they changed name on "Песняры" for participation in IV All-Union competition of variety artists and took second place (first didn't exist).
At the beginning consisted of:
Владимир Мулявин - art-director, leader, vocal.
Александр Демешко - drums, vocal
Владислав Мисевич - flute, saxophone, vocal
Валерий Яшкин - bayan, keyboards
Леонид Тышко - bass-guitar, bass-vocal
Валерий Мулявин - guitar, vocal
Валентин Бадьяров - violin
Валерий Гурдезьяни - trombone
Леонид Борткевич - trumpet, vocal

In 1998 splitted to Песняры (2) and Белорусские Песняры. After the death of Vladimir Mulyavin in 2003 new band Белорусский Государственный Ансамбль Песняры was formed - and many subsequent bands by former members.

Actually there are a lot of related/disputed bands using name of the band and their songs (in chronological order):
Лявоны (1968-1969) (until name change)
Песняры (1969-1998) (original band)
Песняры (2) (1998-2003)
Белорусские Песняры (1998-present)
Белорусский Государственный Ансамбль Песняры (2003-present)
Песняры под управлением Леонида Борткевича (2003-present)
Песняры И. Свечкина (aka VIAPESNIRI) (2004-present)
Лявоны-Песняры (2005-2007)
Лявоны (2) (2008-2012)

Related sub-projects:
Молодёжная студия ансамбля "Песняры" (1986-1987)
Студия "Лявоны" при БГА "Песняры" (1996-1998)