Yes, Virginia, there is a guitar that tunes itself!
By Dan Day
Musician’s Friend Staff Writer
Like many of you, I’m just a little skeptical when somebody announces they have a guitar that tunes itself, even if that somebody is Gibson. I’ve got some questions I want answered: Is this system going to be big, clunky, and ugly? Does it do open tunings? Can I add my custom tunings? And will it really tune my guitar quickly and accurately? Is it easy to use? Until now, there have been several daunting requirements in the design of a self-tuning guitar. You need to have microprocessers that are small and lightweight yet are sensitive to accurately detect the pitch of the guitar strings tuning and smart enough to calculate how much the strings need to be adjusted to achieve the desired tuning. You need powerful yet lightweight motors to adjust the tuners. The self-tuning system should be visually integrated into the guitar. And, perhaps most critically, all of this technology should not be too expensive. If you’re in a hurry for answers, I can tell you the Gibson Robot Guitar really does work—surprisingly well, in fact.
The Robot Guitar features Gibson’s 490R/498T pickup combo, just like a Les Paul Custom. The 490R’s Alnico II magnet delivers that warm, solidbody sound, with a slight, upper-midrange boost. The 498T has an Alnico V magnet. It’s noticeably hotter, with a crisp high-end. The body of the Les Paul version is the traditional mahogany back/maple top, but it’s chambered for light weight. Like all Gibsons, this guitar has a nitrocellulose clear coat.
Viewed from the front, the Robot Guitar looks like a regular Les Paul or SG. Closer examination reveals the three major components of the self-tuning system: the Master Control Knob (MCK), Powerhead locking tuners, and the Tune-Control bridge.
Here’s the basic operation: The MCK is used to select standard or open tunings including E, G, and DADGAD. The strings are lightly strummed. The control bridge monitors the pitch of the strings and instructs the motorized tuning keys to adjust the strings until the MCK blinks blue to indicate they are in tune.
A closer look
The MCK replaces the bridge pickup tone control. Easily identifiable, the knob has an optical lens/LED display on top. It’s a push/pull operation—pull up on the knob to activate the self-tuning system. It still acts as tone control when pushed back into place. Pulling out the MCK kills the volume output, so you and your audience don’t have to endure the sounds of a guitar self-tuning. When the system is activated, the LED display on the top of the knob lights up in red letters. Turn the knob to zero to select Regular Tuning, or select a letter that stands for an open tuning such as G for open G tuning. The LED shows flat and sharp symbols in red. To activate, press down on the optical lens. All the string LEDs shine red. Lightly strum across the strings and the Powerhead tuners begin tuning. Each of the six Powerhead tuners is a servo peg in a standard housing that contains gears, a motor, and electronics. Although larger than standard tuners, they are actually smaller than you would expect, given how powerful they need to be to tune the guitar. The Powerhead tuner set is actually 15 grams lighter than Gibson’s standard Gotoh tuner set!
The Tune-Control bridge is where the tuning operation begins. A microprocessor located in the back cavity contains wiring for the volume and tone pots. The bridge uses a built-in piezo pickup to measure the pitch of each string. Look closely and you can see the wiring underneath the tailpiece and the bridge that connects them to the controller. Electrical power and tuning data are relayed to a CPU—central processing unit—on the back of the headstock via the strings. The CPU then issues instructions to the Powerhead tuners.
How well does it work?
I charged the Robot Guitar by connecting the included battery charger to the guitar’s output jack with a standard guitar cord. The LEDs on the Master Control Knob confirmed that the system was charging. From one to 10 flashing LEDs show the charge level of the two onboard rechargeable AA batteries. It took about 90 minutes to get to 10, a full charge. Once fully charged, the batteries are good for 250 or more tunings. Charged and ready to go, I was eager to try out each of the tunings and see just how easy and accurate the Robot Guitar’s self-tuning system is.
Because the guitar was already in standard tuning, I turned the knob to E for open E tuning and the EADGBE LEDs lit up red. I brushed across the strings about a dozen times in each direction to keep them vibrating so the controller could keep measuring the changing string pitch. Although the operation was fairly quiet, more than one observer commented that with its quietly whirring motors it sounded like RoboCop—hence the name Robot Guitar. I watched as each of the LEDs began turning to green. The A string and low E seemed to lag behind, so I lightly plucked each of them until they turned green. When all six string LEDs turned green they began flashing blue and then stopped—I had achieved open E tuning in less than 15 seconds. Pushing the MCK back in, I was ready for some Bo Diddley or Elmore James action. Switching back to another tuning proved to be quite easy—I just pulled out the MCK and turned it all the way to zero. Again it only took a few strums to get back to standard tuning.
Here’s how Robot Guitar let me store a customized tuning that I created by manually adjusting the tuning: First, I resisted the impulse to just reach up and monkey with tuners without disengaging them first. I pulled each tuner away from the peghead so I could manually adjust the string—if I hadn’t done that I could have damaged the Powerheads. My custom Jandek-tuning consisted of de-tuning each string to create an unnerving dischord—a tuning I could easily recognize. I saved the tuning by replacing the dropped-D tuning preset.
Standard tuning of A=440Hz can be recalibrated from 435-446Hz. Reference Tuning mode lets you disengage a tuning peg, tune that string to a reference pitch—another instrument—then have the system tune to that reference pitch. To change strings, I used the String Down Mode to unwind the strings and String Up Mode to wind up new strings—necessary steps to ensure the accuracy of the system. The Robot Guitar also allows you to quickly and correctly set intonation—a very welcome feature! These are just some of the powerful functions that are controlled via the MCK.
Features & Specs
Robot Guitar self tuning system:
Les Paul/SG features: