The Komische Oper offers radical productions of opera old and new. There is an established company of singers there who, in contrast to some of the perhaps grander opera houses in other countries, work together as an ensemble. The singers are indeed stars but they don't seek to outshine the operas they perform. Some productions are indeed radical and Mozart's "The Abduction from the Seraglio", which has just ended its run, could not, I feel, have been shown in London - it was both too raunchy for English tastes and probably too hard-hitting. It was however a serious and valid interpretation of a well known opera.
The theatre has a modern facade and a wonderfully ornate interior. If you are in Berlin for a few days at least I recommend you see a production at the Komische Oper. People of all ages go there and while some are clearly all dressed up, a majority dress simply and go for the music - which is as it should be.
Of the three main opera houses, the Staatsoper (Unter den Linden) is the poshest. It's very elegant but its bars are a bit cramped and the staff a bit flunkified. Most of the audience are smartly dressed. The Komische always sings in German; if you can cope with that it has interesting productions. The audience there are regular goers rather than people making an occasion of it. Sit high up - if bored you can always admire the unexpected statuary and mirrors decor.
Deutsche Oper is a bit marooned in the old west, but actually has the most comfortable public facilities. Sit in the long rake of the stalls rather than upstairs. They're all reasonably priced by UK standards, and usually have tickets available at short notice/on the day
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