The second publication in the Millennium Kopprasch series by Jeffrey Agrell is Harmony Kopprasch.
For me personally this volume is much more fun to play than was Rhythm Kopprasch (reviewed here). Why that is the case is hard to pin down exactly, as both are twisted versions of Kopprasch in their own way. But if I had to try to pin it down the harmony book is very inventive in harmonic language. Maybe also it is just fun to play Kopprasch with a bunch of “wrong” notes after years of playing the right ones, or more fun than playing them with the “wrong” rhythms anyway.
In any case, in this volume the rhythms are the same as the original but the note patterns are altered. They have the same general shape as before, but the harmonic content is different.
I found this volume to be very approachable. For teachers out there, it is also very worth noting that this volume should be of real help for working on the topic that everyone loves, accuracy. The patterns make sense and are made clear by Agrell; it is your job to simply follow the new patterns correctly.
As with Rhythm Kopprasch, Harmony Kopprasch is nicely printed and affordably priced. Especially if you are an old hand at Kopprasch, treat yourself to a bit of fun, this is a fun book, one that also should be of real use to horn teachers out there. For more information, the listing on Amazon is here.