One place I always visit with great pleasure is the Concertgebouw. The building itsself is well known for its very good accoustics. But the reason I come here is of course to hear classical music played life. My musical tastes are rather ecclectic and classical music is one of them.
Dress Code: Classical music has the reputation that it is for stiff old people only and the dresscode accordingly. But one website stated that you are coming for the pleasure of hearing good music, how you dress is then not important.
In 1883 the construction for the Concertgebouw -Amsterdam's Concert Hall for classical music, designed by Adolf Leonard van Gendt- started. At the time the location was an empty polder. More than 2000 poles were used to give the foundations a solid anchor.
In 1888 the building was opened with music from Wagner, Händel, Bach and Beethoven.
From1985 till 1988 a new Main entrance was created at the J.W. Brouwersplein with a glass foyer designed by van Pi de Bruijn.
The performances are not limited to classical orchetra's; I've seen King Crimson And later Curved Air perform at the main hall. Many more popgroups have been there too.
Dress Code: Depends on the type of concert.