The JDR Trochilus (Bushman Game Changer) Harmonica: A Game Changer Indeed
- Liam Ward
- May 6
- 7 min read
The JDR Trochilus harmonica — also branded in the USA as the Bushman Game Changer — is a fascinating new hybrid instrument that blends the feel of a diatonic with the chromatic flexibility of a slide harp, all in a compact, easy-to-handle design. Think of it like having a C harp and a Db harp packed into one powerful tool — with a whole lot of expressive possibilities added on top.
What is the Trochilus/Game Changer harmonica?
At its core, the Trochilus is a Richter-tuned harmonica with a slide. Like a chromatic harmonica (e.g. Hohner 270 or CX12), pressing the slide allows you to jump up by a semitone (half step) — but unlike traditional chromatic, it has an innovative narrow-slot design which means it maintains all the bendability of a diatonic.
Without the slide, it behaves exactly like a standard 10-hole diatonic — full bends and all. With the slide pressed in, you access an additional set of notes (like switching from a C harp to a Db harp instantly). You can bend just as many notes when the slide is pressed in, doubling the amount of bendable notes on the harmonica.
Now add to this that the Trochilus is designed for full overblow and overdraw capability — and suddenly, your expressive range explodes. You can play chromatic lines without relying purely on tricky overblows... but if you want overblows, they’re there like on any standard harp.
What's the Note Layout of the Trochilus/Game Changer?
The Trochilus/Game Changer harmonica is currently available in three different tunings. This review is for the 'Blues' (Richter-tuned) model, with the blue comb. (More on the other tunings below.)
The Trochilus harmonica contains all the notes of two standard harmonicas (key of C and key of Db). Here are the note layouts for standard C and Db diatonic harmonicas (including all bends and overbends):
That's already lots of notes. But the Trochilus contains all of the notes from both of the above harmonicas - in one instrument! Without bends or overbends, you have the following notes:
If you add bends, you have the following notes:
Finally, adding overbends gives you the following note layout:
This means that with repeats, the comparison is as follows:
Standard diatonic harp: 42 notes
Trochilus harmonica: 84 notes!
This is a mind-boggling array of notes, and an incredible engineering achievement for such a compact harmonica.
Trochilus/Game Changer Harmonica - Key Features
Let's look at some of the key features of the Trochilus harmonica:
No valves – no sticking, no warming up, easier maintenance.
Bonus bending – normal bends and bends on the slide notes.
Overblows and overdraws – available for full chromatic runs or phrasing options.
Equal temperament tuning – good for single-note melody work and modern playing.
Ergonomic design – comfortable, slim body that feels great in hand.
Approx. $80 price – or £80 in the UK.
Playing a Trochilus allows you to do lots of things that would normally be very difficult. You can move licks to different octaves where they would be very difficult on a standard harmonica. You can create smoother transitions in phrases, and you can avoid overblows and overdraws as much as you want or need to, because the note will be available elsewhere either as a bend or even a stable note.
Why does the Trochilus/Game Changer harmonica have two names?
Throughout most of the world, this harmonica is being marketing as the JDR Trochilus. JDR is the Chinese company producing the harmonicas. I guess they chose the name 'Trochilus' because of the bird phylloscopus trochilus - whose common name is the Willow Warbler (geddit?). Some other hummingbirds also have trochilus in their scientific names. The word 'trochilus' refers to a legendary bird described in ancient Greek texts.
In the USA, this harmonica is being sold by Bushman under the name Game Changer. The name makes sense, but you'd have to speak to JDR or Bushman to find out why they aren't marketing under a consistent name worldwide. It does seem a strange decision to me.
A (Brief) History
The idea of a diatonic-chromatic hybrid harmonica isn’t a brand-new one. Hohner's Koch chromatic from the early 20th century used a similar "diatonic plus slide" concept — and it even showed up in recordings by Little Walter (e.g. "Oh Baby"). The Koch, however, was leakier, bulkier, and based on an upper-lower reed arrangement like a traditional chromatic.
The Trochilus refines the Koch approach by:
Using narrow reed slots for better air-tightness.
Much more responsive, like a standard diatonic.
Sleeker design — it’s thinner and smaller than the old Koch.
The Trochilus project was developed by Chinese company JDR, a new name in the world of harmonica design, with input from Bun Du (see his Facebook posts for more tech details).
Other makers (like Hering) have also dabbled in similar ideas — but the Trochilus seems to have struck a much better balance between flexibility, reliability, and diatonic "feel."
Fun fact: I asked my friends at Hohner whether they planned to bring back or update the Koch design, but sadly, they have no current plans.
Trochilus Harmonica - Size and Feel
The Trochilus is roughly between a standard diatonic and a small chromatic in size. Hole spacing is slightly wider than on a typical 10-hole blues harp, which takes a little adjustment if you're used to diatonic harps. Here is the Trochilus (centre) compared to a Hohner CX12 chromatic (top) and a Hohner Special 20 diatonic (below).
You can see that the size of the Trochilus is somewhere between a diatonic and a chromatic harmonica.
Take the cover plates off and you get a close-up of the reed plates — it's a very cool design to squeeze in so many reeds!
Trochilus Harmonica - Sound and Playability
Let's look at how the Trochilus actually plays.
The Good:
Chromatic scale available without relying on difficult overblows.
Double-reed bends open new emotional phrasing possibilities.
Stable notes: You get multiple ways to find the same note (e.g., natural, bent, slide, overblow) — great for phrasing flexibility.
New bending options: You can bend notes that you can't on a standard Richter harp — for example, the 4 blow is unbendable, but you can replace it with the equivalent -3s which is bendable like the standard 3 draw note.
Feels intuitive: Even if you’re a conservative player, you’ll find your way around fast - then incorporate the extra notes at your own pace.
Amazing for studio/session work: When customers demand impossible lines, now you can actually deliver!
The Weird (but Cool):
You can - in a sense - play in two positions on the same harmonica in the same key - e.g. playing 12th position (tonic note -2//) without the slide, and 5th position (tonic 2 blow) with the slide pressed in. This is because you've basically got two harmonicas in one instrument.
The box looks like a case for your reading glasses! 😎
The Bad:
I find the tone is not quite as dark and rich as I would like, especially on higher keys.
Thin-sounding bends at lower and higher key models.
Shallow mouthpiece — not beard-friendly! (Hairs - and even tongue - may get caught.)
Trochilus/Game Changer - Free Harps Tabs and Tunes
The Trochilus makes a whole host of popular songs much easier to play. It also opens up a world of possibilities for players who want more without the challenge of learning full overbending technique. I've tabbed out some famous songs which the Trochilus really is a game-changer for! Click below for the free harp tabs:
Available Keys and Tunings for the Trochilus
The Trochilus comes in three basic tunings:
Blue (Blues tuning) – standard blues layout, called Richter. (This is the tuning we've been looking at in this article.)
Red (Pop tuning) – Paddy Richter tuning for easier melodic playing.
Yellow (Solo tuning) – traditional chromatic layout.
The keys currently available are: C, A, Bb, D, G, Low F. I think the idea behind the limited options is that you're essentially buying two harmonica keys in one so you don't need to buy all 12 keys, because when you press the button you have a new set of notes. This is true for basic playing, however the slide useage changes dramatically if you're playing the standard key (C) or the slide-in key (Db) so you will have to learn to play "slide in" and "slide out" if you want to master all the available keys. In addition, because they are selling the six most popular keys, rather than six equally spaced keys, there is no key of E available (they would need to produce either a key of Eb or key of E instrument for that).
The Trochilus / Game Changer - Conclusion
One thing I have to say about this harmonica is that it's like suddenly unlocking "cheat codes" for familiar tunes! It may be overwhelming for some traditional players — the range of note options can be a double-edged sword - but I would counter that this is the best harmonica out there for expanding your chromaticism without a steep learning curve.
The Trochilus is a seriously exciting addition to the harmonica world. It’s perfect for players who find overblowing hard but still want full chromatic access on a diatonic-style harp.
For me, it presents as a "no excuses" harmonica — if you can’t find a way to hit the note you need, it’s probably your technique or practice, not the harp itself.
The crazy love child of a diatonic and a chromatic? Absolutely. And I’m here for it.
Hopes for the Future of the Trochilus
Full 12-key range
Low-pitched versions
Half-valved models for even more expressive bends
Four-octave models (with added low octave)
More tuning variations (to open up some crazy avenues)
Game Changer Links & Resources
JDR Game Changer / Bushman Trochilus - Amazon links:
Lo F - https://amzn.to/4lHfY0f
I hope you've enjoyed this introduction to the Trochilus / Game Changer blues harmonica.
Want step-by-step harmonica lessons?
Why not try my online harmonica school? Start your free trial today! Click here for more details. (P.S. You will need a standard diatonic harmonica for my school.)
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