Though the place is really small (you should absolutely book a table in advance) there's a nice music atmosphere in that place. All the times I've been there it was a really good and each time different jazz/blues music there.
If you are a jazz lover and want to taste some jazz in Prague or if you want to have a romantic evening with your beloved it's a right place. The bands and singers are changing during the week, check the actual program at the website.
There are just about 10 tables there, so book a table beforehand (it's enough to make a booking by phone).
Su-Sa: 11:00-02:00