They are produced in Yamaha workshops by highly trained craftspeople with very similar specifications and manufacturing processes as we use on our top of the line models. And every single instrument is stringently test-played and inspected by an expert. This is why some top artists have commented that Yamaha standard models are very close to pro trombones in quality, yet are much easier for beginners to play. The standard models are durable, high quality trombones which offer a perfect entry into the world of music.