A New Idea in a Changing World (2012–2013)

In the early 2010s, musicians were suddenly creating more music outside of traditional studios. Laptops were getting lighter, the iPad had become a serious creative tool, and mobile music apps like GarageBand were pushing the boundaries of mobile production.

But MIDI keyboards didn’t keep up.

Most portable controllers were plastic, wobbly, and couldn’t deliver meaningful expression. They were travel gadgets — not instruments.

That gap sparked an idea at CME - the original developer of the Xkey:

Can a portable keyboard feel like a real musical instrument?

This question shaped the earliest Xkey prototypes: a machined aluminum body, full-size keys in an ultra-slim design, and performance features no other mobile keyboard offered at the time — especially polyphonic aftertouch.



Early Xkey models produced by CME can be recognized by their USB micro-B connector and the distinctive CME logo printed on the rightmost key. Later Xkey micro-B models can be recognized by the micro-B connector only. These Xkey models were not produced under the wings of CME, so the logo was removed

Building an Ultra-Slim Instrument (2013)

After months of development and internal testing, the first Xkey 25 arrived in late 2013. It wasn’t just another MIDI controller — it introduced an entirely new design philosophy built around portability without compromise:

• Full-size keys in an ultra-slim 4 mm aluminum chassis

• True polyphonic aftertouch

• Pressure-based pitch bend and vibrato

• A strong, single-piece unibody enclosure inspired by Apple’s design philosophy

• Seamless compatibility with iPad, iPhone, macOS, and Windows

Musicians around the world immediately took notice. For the first time, a mobile keyboard felt premium, expressive, and genuinely travel-ready.

Growing a Global Community (2014–2015)

As more players discovered the instrument, a new creative culture emerged around it.

Producers used Xkey on airplanes, composers used it in hotel rooms, and performers took it backstage on tour.

The idea spread quickly: Music should happen anywhere — without compromise.

And with this global adoption came new requests:
“Can we have more keys?”
“Can it be wireless?”

At that time both were in development at CME

Xkey 37: A Larger Range, Same Design Philosophy (2015)

Listening to musicians, CME expanded the line with Xkey 37, offering:

• A wider playing range

• The same aluminum construction

• The same expressive keybed

• A new Xcable system for pedal and MIDI I/O

• A still-portable footprint

The Xkey37 featured a dedicated port for the Xcable — a breakout cable that provided MIDI Out, sustain pedal input, and expression pedal input. It became a favourite for touring musicians and mobile producers who needed more range without moving to a full-size keyboard.

Later, when the supplier stopped producing the custom connector required for the Xcable, the breakout cable could no longer be included with the instrument. As a result, the model was reissued as the Xkey37 LE, sold without the Xcable.

This is also why the legacy Xcable (2015) is only compatible with the legacy Xkey37, and cannot be used with the new Xkey versions we will talk about later in this blog.


Early Xkey models produced by CME can be recognized by their USB micro-B connector and the distinctive CME logo printed on the rightmost key

Xkey Air: Wireless Freedom Arrives (2015–2016)

The next breakthrough was Bluetooth MIDI with ultra-low latency. This was still a new technology at the time, but Xkey Air proved it could work reliably — especially with iOS and macOS.

It delivered:

• Instant wireless pairing

• Long-lasting rechargeable battery

• Full key expression over Bluetooth

• Complete freedom from cables

Xkey Air quickly became the go-to solution for creators who wanted true mobility without sacrificing professional control. Both of the original USB micro-B models were released in wireless versions, retaining the micro-B connector while adding Bluetooth 4.0 MIDI for cable-free performance.

Early Xkey Air models produced by CME can be recognized by their USB micro-B connector and the distinctive CME + Bluetooth logo printed on the rightmost key

Years of Refinement — Firmware, Software & Community (2016–2020)

As the hardware stabilized, the ecosystem expanded and the Xkey Plus Editor was introduced.

This companion software allowed fine control over:

• Velocity curves

• Aftertouch response

• Custom key assignments

• Advanced configurations

Firmware upgrades

CME kept refining Bluetooth performance, improving compatibility, and optimizing expression sensing. By 2020, the Xkey had become a modern classic — instantly recognizable and loved for its portability and expressive feel.

A New Chapter: ESI & Artesia Take Over Development (2020–Present)

In 2020, ESI Audio from Germany and Artesia Pro from the USA took over the further development and production of the Xkey series.  

This began a new era focused on:

• Modernizing the hardware

• Extending the family of instruments

• Bringing Xkey to new generations of musicians

Today, all X Series development is led by ESI Audio and Artesia Pro — with Artesia serving customers in the USA, and ESI Audio supporting the global market, especially throughout the EU and UK.

Xjam (2022): Expanding Creativity Beyond Keys

In 2024, ESI and Artesia Pro expanded the X Series with Xjam, a compact and highly responsive pad-based MIDI controller designed for modern producers and performers.

Built for creators who work on the move, Xjam offered:

• 16 dynamic performance pads

• Tight, responsive finger-drumming

• A lightweight, portable footprint

• Seamless integration with DAWs, laptops, and mobile devices

• A natural complement to Xkey for beatmaking and performance

• USB-C plug-and-play functionality paired with a TRS MIDI Out port

Xjam marked the beginning of the X Series evolving beyond keyboards — bringing rhythm and groove into the lineup while preserving the same design principles of portability, expression, and reliability.

The New Xkey USB-C series (2025)

The second major update under ESI and Artesia was the full transition to USB-C, bringing the Xkey in line with modern devices and workflows. The Xkey Plus editor was expanded as well, now supporting macOS, Windows, and iPadOS, giving players far more flexibility when customizing their instrument.

To enhance the creative experience from day one, the updated Xkey package also included Bitwig Studio 8-Track, Cubasis LE, and Wavelab LE.

Despite these upgrades, the new Xkey models stayed true to the original design philosophy, while improving durability with modern connectivity.

You can easily identify the latest USB-C versions developed by ESI/Artesia: they feature the Xkey logo placed directly beneath the pitch-bend button on the left side. The original CME logo is no longer printed on the keys, giving the new models a cleaner, more minimal aesthetic.

The new Xkey37 also features a dedicated port for the updated Xcable — an expansion cable that provides 5-pin DIN MIDI Out plus inputs for both a sustain and an expression pedal. This new Xcable (2025) is not compatible with the legacy CME Xkey37 (2015), and the old Xcable (2015) cannot be used with the new Xkey models.

Today’s Xkey USB-C models produced by ESI/Artesia can be recognized by their USB-C connector and the distinctive Xkey logo printed on the left side underneath the pitch bend button.

Xsynth (2025): The First Portable Synth Engine in the X Series

In 2025, ESI and Artesia introduced the next major milestone: Xsynth, the first standalone portable synth engine designed specifically for the X Series ecosystem.

Xsynth delivered:

• A powerful, lightweight sound engine for mobile production

• Deep expression compatibility with Xkey’s polyphonic aftertouch

• Smooth integration with Xjam, Xkey, and other X Series tools

• A compact design ideal for travel-friendly setups

• A modern sound palette tailored for electronic, ambient, and cinematic music

With Xsynth, the X Series shifted from being a collection of controllers to becoming a complete creative ecosystem, offering both expressive input devices and a portable, high-quality sound engine.

2026: The New Xkey Air — Wireless, Modern, and Reinvented

In 2026, ESI and Artesia introduce the next generation of Xkey Air, fully redesigned for today’s wireless workflows. The updated model delivers:

• Significantly improved Bluetooth performance

• Modernized, longer-lasting battery technology

• USB-C for both charging and wired operation

• Enhanced key-expression algorithms for even greater responsiveness

• Broader compatibility across current operating systems

• Full Xcable support (sold separately) for MIDI expansion

Staying true to the original vision, the new Xkey Air pushes wireless creativity further than ever — combining the freedom of Bluetooth 5 with the precision, expression, and portability the X Series is known for.

In addition, both new versions of the Xkey25 Air and Xkey37 Air include a dedicated port for the updated Xcable — an expansion cable that adds 5-pin DIN MIDI Out along with inputs for both a sustain and an expression pedal. The new Xcable is not compatible with the legacy CME Xkey models, and the legacy Xcable cannot be used with the new versions.

Today’s Xkey Air models produced by ESI/Arties can be recognized by their USB-C connector and the distinctive Xkey Air logo printed on the left side underneath the pitch bend button, and the Bluetooth logo printed on the rightmost key

A Legacy That Continues

More than ten years after its debut, the Xkey still stands out in the crowded MIDI controller landscape. It remains one of the very few portable keyboards that meets the standards of professional and mobile musicians.

And now, with ESI and Artesia continuing the work, the X Series is evolving into a broader ecosystem — portable keyboards, pads, synths, and wireless tools designed for creators who want professional expression anywhere.

What began as a bold experiment in 2013 has become a decade-long story of design, innovation, and musical freedom.