There are three great orchestras in Munich:
Symphoniorchester des Bayerischen Rundfunks under Mariss Jansons; Bayerisches Staatsorchester under Zubin Mehta ( Kent Nagano as his successor); and Muenchner Philharmoniker under Christian Thielemann.
If you are avid music fans who like going to rehearsals as well as concerts, you could attend open rehearsals organised by Bayerischer Rundfunk for 8 EUR (for students and those unemployed, disabled or on social benefit the admittance is free).
If not, you could always go to a good concert in Munich. Personally it is worth going to any concert performed by the first orchestra mentioned above ('Bavarian Radio Symphony Orchestra' in English), as the orchestra direction has revived under the new chief conductor (Mariss Jansons who holds another chief conductorship for Royal Concertgebouw Orchestra of Amsterdam).
Munich is also cultural crossroads where world-renown artists/musicians come to perform on a frequent basis. So if you are around Munich for a couple of days, it is always a good idea just to see what's on in Munich by looking at the monthly event leaflet which you can get from the Tourist board centre at Hauptsbahnhof.
www.br-online.de/kultur-szene/klassik/
www.staatsorchester.de
www.mphil.de/mphil/de/
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