The violin and accordion at an intimate place in Budapest. That's a better place to hear these instruments than a prestigious concert hall. I had a similar experience at Preservation Hall in New Orleans in 2005. P Hall was a small cave of a room with walls of rocks and 3 benches for about 20 people. The unamplified brass and piano were exciting. All for $6 for 30 min of music, including audience requests. Now $40, still a great deal, in comparison to a concert hall where most seats are distant. For small ensembles, cafes are the best. They have small ensembles in large halls just as a matter of economics, not for the optimum way to hear them.
In NYC subways, good musicians perform on the platform between the noise of trains coming. Get close, and throw them some change for 1-2 minutes of music. You'll learn more than from going to audio shows, dealers or concert halls.