July 4

Crowd Creation 2.0: Line6 Variax Wireless VDI by Christian Graffe


Christian Graffe designed a wireless system for the Line 6 Variax VDI

Taking crowd creation to new heights

This blog tells the story of Christian Graffe who developed a wireless system for the Line 6 Variax VDI based on CME's WIDI Bluetooth MIDI technology.

The goal is to explain in detail how the process went and invites you to participate in the next steps of this project. To get to that point, let's first talk about what crowd creation is and then briefly introduce the different technologies.

After that, the floor is completely up to Christian, who explains this crowd creation project in detail. 

Currently we are looking at a solution that uses WIDI Jack with a dedicated Variax VDI accessory cable as shown in the image below.

WIDI Variax VDI prototype I

What is crowd creation?

CME introduced its first crowd creation program in late 2019 with the introduction of a rough draft of WIDI Master. The basic idea was to involve the community in the development process to deliver products perfectly adapted to the needs of the people who will work with them.

With the introduction of iWA in late 2022, a second project was introduced that brought another wireless innovation to the market. While the WIDI project was entirely about wireless MIDI via Bluetooth and resulted in six different products in three years, iWA introduces wireless audio transmission with near-zero latency.

Who knows, maybe iWA is the technology needed to take Christian's VDI project to the next level....

What is Line 6 Variax?

The Line 6 Variax is a type of electric guitar that combines traditional guitar design with advanced digital technology. It uses built-in electronics and software to emulate the sounds of various classic guitars, allowing players to switch between different guitar models and tones with ease.

This means that a single Variax guitar can replicate the sound of different iconic guitars like a Stratocaster, Les Paul, or Telecaster, giving guitarists a wide range of sonic possibilities without needing multiple instruments.

What is WIDI?

WIDI stands for Wireless MIDI, and it refers to a technology that enables the wireless transmission of MIDI data between musical instruments, computers, and other MIDI devices.

Instead of using traditional MIDI cables, WIDI utilizes Bluetooth to establish a connection, allowing musicians to send and receive MIDI information without the constraints of physical cables.

This wireless functionality simplifies setups, enhances mobility, and enables more flexible and convenient integration of MIDI devices in various musical contexts.

That advantage was picked up by Christian Graffe at an early stage, allowing him to develop some neat solutions for his specific setups. And one of them is discussed today....

Modified WIDI Master

Variax Wireless VDI (CME WIDI): Journey Past, Present and Future by Christian Graffe


7 years, that is the time it took me for me to decide it was time to get a Line 6 Variax since the first day I got interested in it. Why did it take me so long? you may ask.

Well, back in 2015 I was definitely sold on the idea of the all in one super versatile guitar and the Variax was the obvious choice. Suddenly during my research I discovered the Autotune for Guitar (ATG) system which basically, when loaded with the full software pack, was a pretty good alternative to the Variax.

I evaluated the pros and cons but what ultimately tipped the scales in favour of ATG, was the availability of a Luthier kit, its more open ecosystem approach and its support of standard MIDI.

When CME released the WIDI Master was a game changer and finally allowed me to go full wireless with no compromises.

Christian Graffe

Leader of the Variax Wireless VDI project

Line 6 Variax

I had been a Line 6 user and owned different products for years but around the same time I went the Kemper profiler route. This was the main reason why I favoured a MIDI controllable system. Unfortunately the Variax was not it and only a VDI equipped system was an option.

During those 7 years I was able to experiment and try out different systems and divided pickup solutions (ie. Roland/Boss, Graphtech Ghost, Cycfi Nu etc).

Mission accomplished

The end result was my holy grail project consisting of equipping a high end PRS guitar with the ATG system in a full wireless set up using a modded CME WIDI Master (PCB) and the Line 6 Relay G10. All of that while avoiding any permanent modification to the guitar.

WIDI variax

ATG guts inside PRS guitar - Featuring WIDI Master PCB

Fast forward

Yet, something was still bugging me. I had never got to try out the Line 6 Variax first hand so I could fully compare its capabilities and how it sounded. So I pulled the trigger after shopping around for a few months (In Europe it was almost impossible to find a Shuriken but I finally did).

As soon as I received my new Shuriken in November 2022, I got to work. My objective was to open up the Variax - not literally - so I could control it with my existing MIDI foot controllers and integrate with my Kemper rig the same as I have with my PRS ATG guitar.

But of course, wirelessly....

The Wireless Variax Digital Interface (VDI)

The VguitarForums has always been a great resource for all things related to guitar DIY and more importantly, all of the advanced guitar systems that have ever existed including the Variax.

The forum and the help of its members was instrumental for the completion of my PRS ATG guitar and now for my Variax VDI experiment.

Unsurprisingly, they also had a thread where the internal VDI structure is described, the pin out of the RJ45 cable and how to mod it so MIDI cables could be used instead.

Internal VDI structure

How come this is not a thing already?

I used the above diagram to start wiring a WIDI Master I had. Very soon I realised that even though the Variax speaks MIDI over the VDI cable, those MIDI lines do not exactly implement the standard electrical MIDI specification.

While it all worked perfectly using cables, I struggled initially to make WIDI work fully. But hey, despite that it WORKED! I could wirelessly change models/presets in the Variax using my iPad and MIDI foot controllers.

How come this is not a thing already?

First prototype dongle style version with heavily modified WIDI Master

I knew that many Variax users have asked Line6 for a Wireless VDI solution for years but it has never materialised. Maybe I am onto something that could benefit all those users? Granted, it will not provide full VDI functionality (no power and no Digital audio YET! *more on this later) but many would happily rock a standard guitar wireless system (ie. Line 6 Relay)

First prototype

This is when I first posted my solution in the Facebook group as well as the VguitarForum. To my surprise (or maybe not), it created a big stir amongst users and interest in the solution.

This is also when the good folks at CME saw the potential that exists with this solution and the Line 6 Variax community.


Remember I mentioned that I struggled to make WIDI work fully? Well, initially the solution only allowed External devices to send MIDI messages IN to the Variax, but not the opposite.

It was a choice between providing power to the WIDI Master or allowing bidirectional communication.....

I wanted to avoid at all costs having to provide external power so with the help of CME themselves- Jerome Dumas (CTO),Thomas Gerbrands and Zhao Yitan - and after a good brainstorming over email and testing with the multimeter, we accomplished providing sufficient power to WIDI while allowing full bidirectional MIDI communication.

Cable adapter version featuring Neutrik Connector

Adding Workbench

The solution now works in both directions IN/OUT and it is technically no different to using the Variax USB interface while connecting to the Workbench software.

Yes, the Workbench HD software will also talk wirelessly to the Variax.

Workbench HD software connecting wirelessly via WIDI

Where do we stand today?

As it stands today, the Variax can be controlled using "any" MIDI controller of your choosing including the Line 6 Helix family of processors using Command Center and the standard MIDI ports.

This finally opens up the Variax to be used with other amp modelling/profiling/cloning/real amp systems whilst not sacrificing control of the Variax.

So my initial goals have been achieved.....

Cable adapter version to work with unmodified WIDI Jack

What's next?

Many Variax users I reckon are happy with their L6 Helix processors and they have figured out their workflow using the native features of the VDI interface.

So my next step was to create a similar adapter but that connects to the VDI processor instead (ie. Helix). Unfortunately, after some testing with my Firehawk 1500 and with the help of some other users testing a Helix floor unit, we found out that for those processors to begin talking to the Variax, they need to do a sort of a handshake/sync that relies on the AES+/- lines of the VDI cable which in my solution is not possible.

At least for now - I am looking at CME iWA technology for a future solution....

Go support this project!

But not all hope is gone, not at all. I came across this old post.....

It relates to the old Line 6 Vetta II amp which also featured a VDI interface. Well, it turns out that the same concept of Wireless VDI I used already existed for quite a while (well before the modern MIDI BLE transmitters were a thing) and according to this post, Line 6 worked with some artists and facilitated (albeit unsupported) an electrical circuit.

Wireless VDI

But more importantly, a Variax W/L setting in the Vetta II 2.5 firmware that bypasses the handshake/syc as explained earlier on, therefore allowing the Vetta natively controlling the Variax wirelessly.

If we could get Line 6 to add a similar setting to the Helix firmware, then we would have a better native integration for those that do not want to get into the MIDI world and just want things to “work”.

This is where I ask for your support to vote for this IdeaScale and hopefully see this implemented in future Helix firmwares...

I am also eyeing how we can use CME's upcoming iWA technology so a full wireless VDI replacement (including digital audio) can be created but this is another story for the future.

Christian Graffe

Leader of the Variax Wireless VDI project

Register today!!

After my initial prototype I received full support from the good folks of CME to move this project forward. If you have not noticed, I am just an enthusiast with limited resources to get this solution to the masses so by collaborating with CME we can bring this to you.

The project is currently active in a dedicated Facebook Group. Feel free to join this journey and make it happen together!


Bluetooth MIDI, crowd creation, WIDI

You may also like

CME WIDI App: Start Guide

CME WIDI App: Start Guide

CME Awards 2023

CME Awards 2023

Leave a Reply

Your email address will not be published. Required fields are marked

  1. Hello,
    As the proud owner of a Variax JTV 89F, I'm very interested in Christian Graffe's project.
    If you need testers, I'm happy to help.
    I also have a question: I already own 2 WJ, is it possible to have only the cable or is the WJ connected to the cable special?
    Bonne continuation


    1. Great to hear this. For getting involved you can connect with Christian via the group shared in the blog. The idea is to use the same WIDI Jack interface and only make available a dedicated accessory cable. So you can use what you have and only by the VDI cable.

{"email":"Email address invalid","url":"Website address invalid","required":"Required field missing"}