It is a place for sale and consumption of drinks (just, like a café, pub or bar) that also offers a concert or theater show. It is a voice taken from French, where it is also known as café-chantant ("café singer").
CAFÉ-CONCERT galicismo to refer to a place that sells cafeteria service and at the same time is a concert and performance hall. Some synonyms, words or similar expressions may be chsntant coffee, concuerto coffee