I want to know the answer to the following question:
When did Armenian pop music become popular?
All the background I'm provided with is that "Richard Hagopian is perhaps the most famous artist of the traditional "kef" style and the Vosbikian Band was notable in the 1940s and 1950s for developing their own style of "kef music" heavily influenced by the popular American Big Band Jazz of the time.". Is that enough to answer the question?