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Tronical Tune

Self‑tuning Machine Heads
Published March 2014
By Sam Inglis

Tronical Tune

Thanks to Tronical Systems, your guitar can now tune itself. Is this a valuable tool for committed guitarists, or a crutch for the lazy and tone–deaf?

It’s easy to become jaded when manufacturers bandy about words like ‘groundbreaking’ and ‘revolutionary’ at trade shows. Most of the time, it turns out they’re actually referring to a minor OS update or a slightly redesigned foot pedal. But, just occasionally, you do get to see something genuinely jaw–dropping. So it was at the Frankfurt Musikmesse about 10 years ago, when a group of us were shepherded into a hotel room for a product demonstration from an unknown company called Tronical Systems.

The Tronical Chronicles

What founder and inventor Chris Adams (who is, despite the name, German) promised us that day seemed far too good to be true. He claimed to be able to turn almost any six–string, steel–strung or electric guitar into an instrument that could automatically tune itself. Not only that, but Tronical’s self–tuning system would be invisible to the audience, didn’t make the instrument heavier or change its balance, and could be retrofitted without any drilling, routing or other damage to the guitar. What’s more, the answers to all the obvious questions were positive: yes, it worked with floating tremolo systems; yes, it could switch rapidly between alternate tunings; and yes, the user could still tune manually, and could store and recall his or her own custom tunings.

Evidently I wasn’t the only one impressed by Adams’ demonstration, because Tronical Systems promptly disappeared. It turned out that Gibson had acquired an exclusive licence to their technology, which eventually surfaced with some neat refinements in that company’s Robot Guitars. However, a combination of high cost, limited production runs and, er, challenging colour schemes has meant that these have remained the choice of rather few musicians.

Tronical and Gibson’s exclusivity deal has now lapsed, and the consequence is that Tronical’s technology is now available to almost anybody. What’s more, it has been further refined since its initial launch, and the new system now fits in its entirety behind the headstock of the guitar, requiring no wiring or replacement of bridge, saddles or controls. The system is available factory–fitted to most Gibson guitars, in the guise of Gibson Min–etune, or, as reviewed here, a kit from Tronical themselves, called Tronical Tune.

Heads You Win

The Tronical Tune system consists of three main components. First, there’s a set of motorised machine heads called Roboheads. From the front of the headstock, these look like conventional locking tuners, but behind it they extend perhaps three times as far as a typical set of Grovers. Second, there’s a rectangular plastic box adorned with LEDs, which contains the battery and the brains of the system. And third, there’s a black plastic plate which sits flush against the back of the headstock, with the machine heads passing through it.

The Tronical Tune system assembled without the guitar. Unlike conventional machine heads, these require no woodscrews, as they fit neatly into holes in the plastic plate.The Tronical Tune system assembled without the guitar. Unlike conventional machine heads, these require no woodscrews, as they fit neatly into holes in the plastic plate.

While the ‘brain’ is common to all Tronical configurations, the machine heads themselves and the plate must precisely match the geometry of your headstock. This means that you need to be careful to order the correct system for your guitar, and also that if you have an obscure model or a custom–made instrument, the chances are that you won’t be able to use it. However, the range of guitars that is supported is already very impressive, including most current six–string models from the likes of Gibson, Fender, Ibanez, Guild, Taylor and Yamaha, as well as many smaller manufacturers. New models are being added on a regular basis, and when I asked if the review system could be made to fit my Larrivée OM3, Tronical got hold of the appropriate measurements and did just that. Neat!

Lock & Load

Everything you need to install the system is supplied, except for the screwdriver needed to remove your existing machine heads, and the instructions are very clear. With a bit of practice, I’m sure that an experienced guitar tech could fit the entire system in five minutes or so, and as promised, there’s no drilling or other invasive surgery. The Tronical machine heads don’t even need to be attached by woodscrews, as they are held in place by holes in the plastic plate. Despite their size, they are surprisingly light, and really don’t change the balance of the guitar. A nice touch is that the review system at least was supplied with the battery fully charged and ready to go. A single charge is enough for several weeks of light–to–moderate use, or perhaps a couple of days of intensive use, and charging is impressively fast.

To the user, the system’s ‘brain’ presents six buttons. Five of these are arranged in a cross shape, with the outer four acting rather like cursor keys for navigating through system options and the central one serving to confirm choices. The sixth button, to the lower right, turns the system on, and combinations of this and the central button access various different modes, of which more presently. There’s no screen, which is perhaps a good idea given the small size of the unit and typical stage lighting conditions! Instead, visual feedback comes from a row of six LEDs labelled with the note names of each string, and several further LEDs around the controls. All of these are capable of displaying a number of different colours, and all are bright enough to be visible even on the darkest stage.

Tronical warn that the system should not be used with string gauges heavier than 0.013–0.056 — a restriction which I suspect will bother few guitarists these days — and I used my usual Martin 0.012–.054 sets. Fitting these to the locking machine heads was relatively straightforward, though the heavy low ‘E’ can be a bit of a squeeze. There are stern warnings about the damage that can be done to the machine heads by over–tightening the locking heads: this should never be done using a tool other than a coin (the one pence piece is the only UK coin that fits!). The manual recommends taking an extra turn around the post with the high ‘B’ and ‘E’ strings, and even then, I found the ‘B’ prone to slippage on a couple of occasions. Stringing the Roboheads: the locking cap needs to be screwed down firmly enough to clamp the string in place, but not so tight as to damage the mechanism. Stringing the Roboheads: the locking cap needs to be screwed down firmly enough to clamp the string in place, but not so tight as to damage the mechanism.

Once you’ve tightened the locking mechanisms, you can power up the system and luxuriate in the sensation of not having to wind the slack strings up yourself! Taking each string in turn from low to high, you hold down the Up button until the tension begins to approach the correct pitch for that string, after which you can simply twang the string until its LED lights up green to indicate that it is in tune. The need to trim and lock the string ends means that it’ll never be quite as fast as restringing a guitar with conventional machine heads using an old–fashioned string winder, but once you’ve done it a couple of times, it becomes routine. However, I don’t think it would really be feasible to change a broken string on stage.

All Or Something

The Tronical Tune system offers two basic tuning modes: all strings at once, or single–string, accessed respectively by pressing and releasing or by pressing and holding the power button. As you’d expect, the first is faster, while the latter is more robust, especially in the face of noisy environments and other impediments. Among the various configuration options is the opportunity to specify how accurately you wish the system to tune each string: settling for the loosest ±3.5 cent option results in speedier tuning, but you can go as tight as ±1 cent.

One thing you notice straight away is that the motorised machine heads make a pretty obnoxious grinding sound in motion, which is easily audible across a quiet stage. They seem to be programmed to operate in the way that most humans learn to tune a guitar, ensuring that they always tune up rather than down to the note, so you quite often find them ‘hunting’ around the note as they go alternately sharp and flat.

As you tune, the note LEDs on the back of the ‘brain’ change colour to indicate what’s going on. Notes that are in tune show up green, while those that are not yet in tune glow red. Yellow indicates that a particular string’s pitch is being measured, and blue that the relevant machine head is in motion. If your string is so far out of tune that it falls out of the pitch ‘window’, it appears purple. In all–strings–at–once mode, you’ll also sometimes see LEDs flash white, indicating that crosstalk between strings is hindering the process. This happens most often in open tunings where multiple strings are tuned inThis photo, taken during fitting, shows the ‘brain’ and the plastic plate overlaid on the back of the headstock. It’s vital that the plate matches exactly the geometry of the headstock.This photo, taken during fitting, shows the ‘brain’ and the plastic plate overlaid on the back of the headstock. It’s vital that the plate matches exactly the geometry of the headstock. octaves: in DADGAD and open ‘D’ tunings, for instance, I often found that the middle ‘D’ string’s LED flashed white. You can adjust various sensitivity parameters by going into configuration mode, but I never managed to overcome this entirely. It’s not a huge problem, though, and you can always go into single–string mode if needs be.

If my experience is anything to go by, a couple of strums in all–strings–at–once mode is usually enough to get three or four of the LEDs lit up green, after which you’ll have to mute the strings and pluck any remaining ones individually. Even at high accuracy levels, it’s pretty fast: not fast enough that you could do it mid–song, but faster than manual tuning, especially where things have drifted quite far to start with. I tested the all–strings–at–once mode’s vulnerability to noise interference by turning up the stereo and tuning next to the speaker, and encountered no problems. However, as mentioned above, it works better in standard tuning than in some other tunings, and in DADGAD, I found single–string mode more reliable and nearly as fast. Either way, getting your guitar in tune does require some attention to what the LEDs are telling you: Tronical Tune is not a magic button that can instantly put your guitar in tune without any intervention from the user. Just occasionally, I found that it seemed to convince itself rather too easily that a string was in tune when it clearly wasn’t, so it pays to check by ear.

An unusual feature of the Tronical system is that on an instrument with a three–aside headstock, the bass–side tuners work backwards. This is relevant because the Tronical machine heads can also be turned manually — and as they have a much lower gearing than any conventional alternative, this can be a very good way of fine–tuning where appropriate.

In Action

Adding Tronical Tune to your guitar changes your relationship with the instrument, in more ways than you’d expect. Some of these are wholly good. If you’ve ever felt daunted at the idea of experimenting with different tunings, for instance, this is the perfect tool for dispelling your fears, letting you easily dabble in DADGAD or beyond and return at the touch of a button to the comfort of standard tuning. I also found myself becoming much more conscious of smalltuning issues, and less tolerant of sloppiness in this department. When your guitar is tuned accurately all the time, the compromises associated with equal temperament really start to annoy you, and for the first time, I found myself hearing that strings were getting old before I felt it.

The flip side of this is that it’s easy to fall into the trap of expecting too much from Tronical Tune. It’s an amazing piece of technology which, by and large, works very well, but it’s not magic, and it needs to be used with care. Nor is this a product for those who simply can’t be bothered. It builds a lot of functions into a small package, with inevitable consequences for the user interface; and while you quickly internalise basic operation, I’m still regularly consulting the manual for less common functions after more than two months’ use.

In short, if you want something that will free you from ever having to worry about tuning again, buy a keyboard. Tronical Tune is for those who are worried about tuning, and are seeking a better way of managing it. It is hugely innovative, but at the same time, it’s a natural and significant evolution of the same technological process that gave us tuning forks and then digital tuners. It’s not cheap in absolute terms, but it’s a small fraction of the price of a top–flight instrument, and when you consider what it actually does, it certainly represents value for money. If you have a single main instrument, Tronical Tune will make it more dependable, more versatile and, ultimately, in tune more of the time, and I think it’s an option that all serious guitarists should consider.


Tronical Tune isn’t the first self–tuning system for guitars: the established alternative is Axcent’s Transperformance system, endorsed by no less than Jimmy Page. This, however, costs thousands of dollars, requires major surgery to the guitar and has to be fitted by the manufacturers. A more realistic alternative for those of us who weren’t in Led Zeppelin is the Line 6 Variax range of modelling guitars — which, among their other capabilities, can emulate alternate tunings without having to be physically retuned.

You’ve Changed Your Tune

One of the major selling points of the Tronical Tune system for me is its ability to switch easily between different guitar tunings. Tweaking the odd errant string between songs is one thing, but anyone who’s ever tried to retune completely on stage will know how much of a downer it can put on a live show. Yet there are many fingerstyle folk players out there who rely on more tunings than can easily be accommodated by spare guitars or cleverly arranged set lists.

The Tronical brain stores three banks of six tunings, which are accessed by the usual series of slightly cryptic button presses. The first bank includes standard tuning along with DADGAD and common variants such as drop ‘D’ and standard lowered by half and whole tones. The second one collects together a selection of popular major–key open tunings such as ‘D’ and ‘G’, while the third bank is available for you to store your own tunings. Even a fairly radical change of tuning in which all six strings are altered can be accomplished in perhaps 30 seconds, which is way faster than I could manage by hand.

Saving a custom tuning is pretty straightforward: following a short series of button presses, you play each string in turn and then choose a slot in which to save the resulting tuning. It’s a shame there’s no option to copy tunings from one slot to another, or rearrange the order of the existing ones — most of the tunings I regularly use are scattered among the presets, so it would be nice if these could simply be brought together in the user bank. It would be good, too, to have more than six user slots, or at least the ability to overwrite factory presets, though it is possible to ‘cheat the system’ by fretting notes as you tune. For example, you could move from standard to drop ‘D’ tuning by fretting the low ‘E’ string at the second fret, thus convincing the Tronical brain that the string was a whole tone sharp.

As mentioned in the main text, each string has its own frequency ‘window’, and any tuning that you store must fit within these windows. Assuming you’re tuning down from standard pitch, the practical limit is about a fourth below standard tuning, and the system clearly finds it harder to pick up pitches correctly as you approach that limit. There have been players who use lower tunings, such as Nic Jones, but the range on offer should be enough for most purposes.

Custom tuning is one of the most exciting features of the Tronical system, then, but I also found it the most unpredictable aspect. Quite often, tunings that sounded fine when stored seemed noticeably skew–whiff when recalled, especially at the low end. Presumably this is because the same margin of error applies to the capturing of a tuning as it does to its recall, so an accuracy setting of ±3 cents might translate to ±6 in this context.

A separate feature allows the guitar’s overall tuning to be pitched up and down to match a reference pitch, which can be invaluable when you need to play along to something that’s not in concert pitch. Unfortunately, though, there’s no provision for tuning with a capo in place. This is a shame, because I’ve yet to discover the capo that can reliably be applied without requiring at least some retuning. I can’t imagine it would be impossible for such a clever system to recognise that detected pitches more than a semitone sharp indicate the use of a capo and to tune appropriately. As it is, once the capo is on, any tuning correction has to be done manually and by ear.

Published March 2014