In the world of music theory, it’s all too easy to get lost in arcane terminology, complex notation, and divergent schools of thought. Yet, every piece of Western music—whether a classical symphony, a jazz improvisation, a gospel chorus or a neo-soul groove—ultimately originates from the same foundational principles of harmony. This is precisely the insight behind the book From Beethoven to Bill Evans: Western Harmony Simplified by Tom Regis.

In this guest‐post we’ll explore:

• Why this book fills a unique gap in music theory education.
• What makes Tom Regis’s background especially relevant.
• Key concepts you’ll encounter in the book (and how they can serve you, whether you’re a novice or seasoned musician).
• Practical take-aways you can begin applying today.
• Who will benefit most — and how to get started.

Why this book fills a unique gap

Many music-theory books focus exclusively on either the classical tradition (counterpoint, species writing, tonal harmony) or the jazz/pop world (extended chords, modal interchange, etc.). Rarely do you find a book that elegantly bridges both, showing their shared DNA—and that’s exactly what Tom Regis does.

On his site, Regis explains the purpose:

“The author outlines a comprehensive system for understanding the elements and construction of harmony, and unlike other harmony/theory books, WHS never loses sight of the forest through the trees.”

In other words: this is not a purely academic treatise for scholars, nor is it a superficial “chords cheat-sheet” for beginners. It offers a system that is accessible and deep—which is rare. For those who feel constrained by one approach (say, jazz chords) yet mesmerised by another (say, Beethoven’s voice-leading), this is precisely the meeting point.

Tom Regis – why his background matters

Tom Regis isn’t just another theory writer. His varied journey lends real credibility:

• He is a pianist, multi-instrumentalist, and Hammond-organ endorsed artist whose credits include working with major names in jazz, Latin, pop and world music.
• He holds classical training, yet also has deep experience in jazz, Latin and popular idioms. This “bilingual” musical fluency gives him unique insight: bridging the rigorous structure of classical harmony with the fluid, improvisatory world of jazz.
• His book is not simply about abstract theory—it is grounded in real keyboard graphics, examples, and a step-by-step approach that welcomes lay-musicians and experienced alike. The book description highlights: “126 clearly labeled keyboard graphics accompany the text … an extensive appendix reviews and further details … designed for the non-reading musician.” tomregismusic.net

In short: when you study this book, you get the benefit of someone who has done the work—performed, composed, taught—and who’s chosen to distill that into a learning guide.

What you’ll encounter in the book: core concepts

Here are some of the key themes and take-aways you’ll encounter in “From Beethoven to Bill Evans”:

1. The seven-note scale as the foundation

Rather than diving straight into extremes (e.g., “altered dominants” or “quartal harmony”), the book starts at the root: the seven-note diatonic system. Understanding how triads, seventh-chords, inversions, modal colours etc. are derived from this system gives you a strong base.

2. Bringing classical & jazz together

The way a Beethoven chord progression moves and the way Bill Evans (or other jazz pianists) navigates harmonic spaces might seem worlds apart—but underlying both are the same mechanisms of tension and release, voice-leading, and functional relationships. The book emphasises these shared mechanisms.

3. Keyboard visuals + staff notation

One of the barriers in theory learning is the notation language + keyboard geography. This book uses clear keyboard‐graphics (126 of them, as mentioned) and an appendix that introduces staff notation for those less familiar. That means whether you “read” music or not, you can still engage meaningfully. tomregismusic.net

4. Exploring various styles

It doesn’t stop at “classical vs jazz”. The book includes chapters on the harmony of blues, traditional jazz, folk, neo-soul and other “exploratory” styles. That means if your interests wander across genres, you’ll still find value. tomregismusic.net

5. Practical system, not just theory for theory’s sake

The word “simplified” doesn’t imply shallow—it implies clarity and systematisation. By guiding you from the ground up, the book enables you to build your own harmonic vocabulary rather than just memorising chords.

Practical take-aways you can apply right now

Here are some actionable ideas you can begin with, inspired by the book’s approach:

• Map your triads on the keyboard: Take a major scale (say C major), build its triads (C, Dm, Em, F, G, Am, Bdim). Then visualise/investigate on your keyboard how each triad relates to other chords in the scale. Understanding this physical layout helps deepen the theoretical connection.
• Voice-leading with classical and jazz in mind: Try a classical progression, e.g., I-IV-V-I in C (C-F-G-C). Then try a jazz styled version in the same key, e.g., Cmaj7 – Dm7 – G7 – Cmaj7. Notice how the voices move (especially inner voices) and how the tension is managed. The book bridges this interplay.
• Explore modal interchange: Borrow a chord from the parallel minor (for example, from C major borrow an A♭maj chord). Understand how its function shifts. Even if you’re not reading ahead in the book, this sort of experiment helps you engage the “non-pure” harmony kinds that inspire blues, neo-soul, modern music.
• Keyboard-graphics make contemplation useful: If you have a keyboard (or software keyboard), print a keyboard diagram or open a visual tool and label the chords as you follow through a chapter. Active engagement is better than passive reading.
• Genre-hopping assignments: Choose a short piece (classical, jazz, folk) and annotate its harmonic movements in terms of “tension/release”, “scale-derived chords”, “borrowed chords”, “voice leading”. Then ask: How might I reharmonise the same piece with a jazz-inspired approach? It’s within the remit of what Regis suggests.

Who will benefit most—and how to get the book

Whether you are:

• A beginner musician (keyboard player, guitarist) who’s always felt ‘theory is too dense’—this book offers a friendlier door.
• A jazz/improvising musician who wants to deepen structural understanding of harmony beyond “licks and voicings”.
• A classical musician/composer curious about how harmony works in more contemporary styles and how to adapt the knowledge.
• A teacher or student looking for a resource that straddles different idioms and offers visual aids.

Getting started is straightforward: The book is listed under Tom Regis’s site and other platforms. tomregisbooks.com+1

Why now is a great time to dive into harmony

In an age where musical styles blend, cross-pollinate and reinvent themselves, the traditional silos of “classical vs jazz vs pop” are breaking down. More musicians are expected to be flexible, adaptive, and fluid in their harmonic thinking. A resource like this helps you build musical literacy rather than just memorising patterns.

Moreover, technology (digital keyboards, notation software, online videos) supports interactive learning; a book like this becomes even more valuable when paired with active practice.

Final Thoughts

If you’ve ever felt intimidated by music theory, boxed in by one tradition, or curious about how the “big names” in music navigate harmony so fluently—then Tom Regis’s From Beethoven to Bill Evans offers a meaningful and accessible path. It acknowledges complexity but focuses on clarity. It respects tradition but encourages exploration. And for any musician seeking to deepen their harmonic vocabulary, this book is a bridge—between genres, between theory and practice, between the keyboard and the ear.

Pick up the book, dive into the exercises, and you’ll find yourself gradually moving from merely playing chords to understanding them—with purpose, freedom, and creativity.