The Budapest Quartet was a string quartet established in Budapest, Hungary in 1886 by Jenő Hubay and David Popper.
Johannes Brahms performed with the quartet and thought it was the best he had heard.
This quartet went under a variety of names. Outside Hungary, it was usually called "Quartet Hubay-Popper". Within Hungary it was called "Hungarian Quartet" or "Budapest Quartet". This was because Hungarians were fiercely patriotic.
They performed for twenty-seven years.(Wikipedia)