Erik Veldkamp does a really great job of writing etudes with a very specific type of player in mind. This book of 21 Melodic Studies for Trombone is a great example of an intermediate etude book that is focused in on the intermediate player that need practice working through the first key signatures. The author explains:
“These melodic studies are written for the intermediate player. They are written up to 3 flats and 3 sharps in both major and minor keys. Each study begins with a scale exercise, so your ears get used to the key before starting the study. A beautiful and idiomatic etude follows each pattern.”
This book is beautifully written and deserve a place in every low brass studio. You can try out the first bit for free in the samples then grab an immediate PDF download above.