About this method, Chris Gekker writes:
David Berties Trumpet Harmonics is a remarkably focused study of flexibility as applied to brass playing. His concise yet comprehensive exploration is unique in several ways.
Firstly, his attention to the role of the tongue in flexibility work, in terms of mobility and utilizing articulation work as part of this practice. This topic has been examined in the past by authorities such as Claude Gordon, and it is gratifying to see it highlighted here. I learned many years ago that any flexibility work that was exclusively slurred, tended to leave me less limber for me, any work in this area must include a dedicated commitment to articulation. At times, I have wondered if I was doing something wrong by exclusively slurring lip flexibilities I do know extraordinary trumpeters who thrive just slurring. I have also heard from various colleagues who agree with my reactions and had witnessed this phenomenon in students. Players who struggling with limberness and lack of mobility, quickly improved whenever a significant amount of articulated work was introduced. Davids attention to this issue is important: he gives sensible, real-world advice that is balanced and practical in the best way imaginable.
Secondly, Davids recommendation to incorporate K tonguing is where his book truly rises to a singular profile in the modern pedagogical trumpet world. Again, this practice protocol was promoted years ago by Claude Gordon. I have noticed in my own practice the benefits of K tongue practice my positive conviction is based solely on empirical evidence, which has been confirmed in those students of mine who followed this advice consistently. My personal experience shows me that K tongue practice has positive effects on other areas of trumpet performance that might not seem apparent but the evidence is strong. Davids comments make real sense to me and give clarity to my longtime intuitive sense regarding this subject.
David lists and discusses the classic works of trumpet flexibility which makes Trumpet Harmonics a valuable reference to our community, especially to beginning students who are now able to learn something of our rich history. Speaking to both younger and older beginning players, there is ample content contained that relates to trumpeters who are investigating flexibility studies for the first time.
As noted at the beginning of this Foreword, Trumpet Harmonics is distinctly concise and compact, yet in content it is a most comprehensive exploration of the general topic of brass flexibility. I extend to David Bertie a deep expression of thankfulness for this book, and I am confident that trumpeters everywhere who have the good fortune to acquire Trumpet Harmonics will join me in their gratitude.