Electric guitars are great, but they’re just so 20th century. You’d think decades of musicians riffing on the instrument would mean there are no hacks left in the humble axe. You’d think so, but you’d be wrong. [Michael], for one, has taken it upon himself to reinvent the electric guitar for the digital era.
Gone are the strings, and the frets have vanished as well. The neck of this guitar is one long custom PCB, looking very sleek with black solder mask. Gold pads serve as touch sensors to give tone data over i2c (from unspecified touch sensing chips) to the Amtel Mega 32u4 at the heart of the build.
With no strings, strumming won’t work, so a laptop-style touchpad serves instead. That means every user interaction with this guitar is with capacitive touch sensors talking i2c. The X and Y coordinates of the touch, along with pressure are sent to the processor over the i2c bus, triggering an interrupt and offering quite a bit of opportunity for sound control.
Said sound control is, of course, done in MIDI. This lets the guitar control a whole variety of synths and/or software, and of course [Michael] is using more futuristic-sounding synths than a pack of guitar samples. That said, what exactly goes on with the MIDI controls is left frustratingly vague. Obviously fretting provides note selection, but does the touchpad just send a “note start” command, or are the X, Y and pressure data used in interesting ways? Is there multitouch support? The video doesn’t say.
How, exactly, the obviously-plastic body of the guitar was manufactured is also left unsaid. Is it a large resin print? SLS? It looks injection-molded, but that makes no sense for a one-off prototype. On the other hand, it looks like he’s selling these, so it may very well be an injection-molded production case we’re seeing being assembled here, and not a prototype at all.
For all the video leaves us wanting more information, we can’t help but admit the end product both looks and sounds very cool. (Skip to the 4:50 mark in the embedded video to hear it in action.) The only thing that would improve it would be a hurdy-gurdy mode. Thanks to [Michael] for the tip, and remember we want to hear tips about all the weird and wonderful hacked-together instruments you make or find on the web.
What this article is missing is a guitarist.
Advertising teaser?
4:50 before we get to hear the instrument and even then it’s quick demo and done?
And all those unanswered questions? What if someone emailed the guy and published the story after those burning questions were, I don’t know, answered?
A guitar has 6 strings played against frets. You can generate music directly from the vibration of the strings by employing a resonator cavity [acoustic guitar], you can detect the string’s motion with a pickup and distort/color/amplify the signals to make new sounds [electric guitar], or you can even use a computer and other electronics to detect what notes are being played on the individual strings and translate that information to MIDI notes… to drive a synth head [midi guitar]. If you’re doing the latter, the strings don’t even need to be tuned to any key normally used, but in fact, could be all the same pitch and gauge if that suited you. The firmware can be set up to sort things out.
In my view all of these constitute some manifestation of what I’d recognize as a “guitar.”
I’ve seen guitar-like instruments with only 3 strings and no frets at all… Justin Johnson famously performs “Ace of Spades” on a garden spade fitted with three strings and a guitar pickup . He does so with a slide, and even this instrument, in my opinion, somehow falls into that “guitar” classification.
https://www.youtube.com/watch?v=-tAEAyHgCec&list=RD-tAEAyHgCec&start_radio=1
The project described here is very cool. It’s interesting, aesthetically-pleasing, has great workmanship, and I look forward to seeing how far the idea can be pushed. As is, it’s already a worthy toy, and probably has meaningful potential as a serious instrument. But aside from the fact that it casts a guitar-shaped shadow in the sun, there is really nothing “guitar” about it, digital or otherwise. It’s a essentially a very novel MIDI keyboard.
I guess if you’re building something like this you have to call it something, and “digital guitar” is probably not unreasonable. I’m just responding with the impressions of a long-time guitarist. I’d be interested in the opinions of other players.
Touch sensing chips are Cypress cy8cmbr3116-lqx (visible briefly in the video)
Thanks for posting this! So this video may seem a bit strange… it’s both specific and vague at the same time, right? I wanted to document the process of building a product in a way that offers a high-level look into how it came together. Electronics, firmware, mechanical. I totally understand that a lot of the details aren’t covered and that’s frustrating for more technical viewers! The video is like a window into how I personally think about embedded systems and the process behind building something from scratch. There’s obviously a lot to cover, and I really wanted the video to be a brief overview that took around ~5 minutes… I’d never made a video like this before and it was a challenge to decide the level of detail.
PS. The touch ICs are Infineon CY8CMBR3116’s. I do have other videos on my youtube channel that go into a lot more details about the MIDI implementation, and LOTs of videos showing it actually being played. This video is on the other hand probably should have been titled “A window into the world of embedded systems development”. Anyway, thank you for posting!
Also – I agree that I’m being very loose with my definition of guitar :)
The string IS the instrument. you don’t just activate a note. you TOUCH that note. HOW you touch that note affects how it sounds. you’ve invented a keyboard of unknown touch sensitivity which will not be guitar string touch sensitivity. you’ve invented a sim. no real guitar player wants this, no pro will use it.
Well, good thing this site isn’t called Make-a-Marketable-Product-a-Day.
i would say making an acoustic guitar or any other instrument, that makes sound via physical vibration is a beautiful art and engineering exercise in tuning and harmonics that is timeless.
that being said, this is an excellent “guitroller” (a portmanteau of guitar and controller as in midi controller).
I’m sure anyone who also reads this blog and dj tech tools will find this and agree this is some kind of new midi controller in a guitar form factor.
I think matching the guitar form factor more intricately will unlock future innovation like how smart watches eventually round display units…
i can def see the community getting excited about making things like these.
like if i were to approach this concept or try to add something new, could we add a theremin interface with adjustable VST/noise generator modulated by the theremin, and tuned for guitar style gestures/strumming, pedals, fx, stomp box etc?
love this idea and think it’s cool af.
Many a guitar has been made similar to this. Though each unique implementation and creation is fascinating. Guitars constantly exist as a question mark of creativity, some things of note are pickups that have existed using lasers, fiber optics and pickups that exist at the end of the strings themselves, allowing for unique shape-work and routing. There’s a couple boutique brands that have been trying to do the whole “Air” guitar thing for some time now. Look into the tech that spun off in and from EMG, lava music, Casio, oPIK.
Better and richer guitarists than I explored MIDI back in the 80s, I even played such a guitar in the ’90s. This project strikes me as criddleware, i.e. crippled hardware. A charitable person would say “[whathisname] has developed a pricier Guitar Hero™.” I’ll say he doesn’t seem to be hurting anyone.
Guitar-shaped MIDI controllers have been a thing for almost as long as there has been MIDI.
I had a Casio DG-20 (which is to musical instruments what a ZX81 was to computers), and later an IVL Pitchrider.
Yamaha, Roland, SynthAxe, etc. have been around since the 80’s.
This one looks similar to some of Starr Labs https://www.starrlabs.com/ products.