When I heard it, it was just before midnight and steam was snaking out of my nostrils as I bustled home on a bitter January night. At first it sounded like the organist had been let loose on the cathedral’s pipes, but distances shrunk and echoes off medieval stones chided me in my ignorance. The Four Seasons were not from the organ, but an accordion, played by a Russian virtuoso, Ruslan Shevchenko, sitting on his three cornered camping stool, huddled under the eaves of the cloisters on Carrer Bisbe. Any day or any night there are world-class tenors, violinists, gypsy guitarists and a host of honky-tonk performers passing the time, making tunes for anyone walking in the old city. Why go to a fancy concert when the best is already available and where a couple of Euros will get you a private encore.