How to tell if you have a Small or Large bore Trombone
Easiest, but not 100% accurate:
-If the student is playing on the same trombone which they started with, it will most likely be small bore as most beginners don't start on a large bore trombone
-Generally Large Bore Trombones have an F-Attachment as picture below (left). Small bore (right).
-If the Diameter of the bell is 8.5" or larger it is most likely large. 8" or smaller, most likely small.
5g, 4g, 3g, 2g, 1g, 51D
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