The firebird is quite an amazing arrangement, not 4/4 time. Not to go off topic.
If you are a Chopin fan.
https://www.youtube.com/watch?v=ef-4Bv5Ng0w
Maybe to heavy. Another folk
https://www.youtube.com/watch?v=tT9Eh8wNMkw
Lots of great info posted by a lot of knowledgeable people here. They are the best! Years of stuff get into the horn. Use it often. Like anything 50 or 100 yrs old a bit of cleaning is not a bad thing. Take it apart.
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