In my limited experience - and also in no particular order (unless noted):

1. Vienna Philharmonic Orchestra
1. Berlin Philharmonic Orchestra
2. Royal Concertgebouw Orchestra
2. Academy of St. Martin's in the Field
2. London Symphony Orchestra
Chicago Symphony orchestra
New York Philharmonic
Atlanta Symphony Orchestra
San Francisco Symphony Orchestra
Royal Philharmonica Orchestra

As I look over this list, I find it humorous in this fashion... A conversation about the differences in European and American orchestra's is what at first piqued my interest to start exploring classical music, and I do tend to like the European greats more so than American (though I do not fault American at all and do have some as my top 10 - easily, like NYP, CSO), especially VPO and BPO at this time. Of course just a couple months ago I had never heard most if not all of these orchestra's - so who can tell what I will like or be on my opinion in say a year from now.

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