Graphtech Hexpander installation Stratocaster

Yes, it's ugly. The routing mishap looks horrible, but fortunately the scratchplate covers everything but the last two ticks. You can also see the damaged foil from where the ball-ended bit got away from me and skittered as I was cleaning out the pickup wire channels. The hefty wires connecting to the tiny circuit board means that it'll go where the wires tell it to go and there's probably less chance of connectors unplugging themselves when you turn the scratchplate over and seal it up if you DON'T attach it to the body with the foam tape-- just my opinion though.


After the hard work is done, the rest is, or should be, cake. I recommend testing the system before sewing the patient up. This can help you localize and troubleshoot problems that are due to bad connections. I installed a single string on the guitar (I later realized, through the wrong saddle, LOL-- I don't play with a wound 3rd string), with the guts exposed and farted around with it connected to a battery and the 13-pin cable. I had an unclear idea of how it was supposed to work, which isn't a good place to be for troubleshooting. It didn't perform as I thought it should and began to wonder whether the thing was broken, or I'd somehow fried the boards. I'd tried various combinations of battery and 13-pin power, disconnected the two circuit boards to see if I could just get the preamp section to work with a single pickup. Then I reasoned that the pots should be wired to get sound. Duh. Finally, I uninstalled my 13-pin cable jack and things started to work as I thought they should. It turns out that my crude routing job forced one end of the ribbon connector to be a little intermittent-- which was cured by grinding out a little more wood. I reassembled the jack with the power on, testing, just to be sure.

Although I consider the Strat control cavity to be fairly voluminous, by the time it's stuffed with wires, there's really not that much extra room. Graphtech tells you to affix the circuit boards with the foam tape they supply, but personally, I don't think it's necessary since the circuit boards probably weigh less then the wires that are connected to them; the stiffness of the wires cushion the circuit and make it go where they want it to go. I also figured that the boards wouldn't like where I would have taped them down and that the wires would resist making sharp bends-- and maybe object by unplugging themselves. With all the wires plugging into the boards, it has quite a high profile. I positioned mine flat on the bottom of the cavity on the side closer to the bridge so that the selector switch's guts wouldn't get in the way. The volume pot side has much more headroom and fewer exposed moving parts. Of course, you should make sure that there are no metal or conducting parts that are going to jab into the circuit board.

I decided not to use the push-pull volume pot for the Mid/Dark switch because I A/B'd the sound and wasn't impressed enough, relatively speaking. Not putting it in left more space for the circuitboard. The Mid/Dark switch probably makes more sense if you've got a simple magnetic/piezo setup and you want more sonic variety; The Hexpander gives you plenty of sonic variety. I think a push-pull pot would probably be more useful as a bypass switch so that you could use the guitar totally unpowered, with just the magnetic pickups. Maybe some day...




This is a fantastic product; I was blown away. The tracking was astoundingly better, with none of the false triggering I'd experienced with the GK-2A. I could play full barre chords cleanly, even with the finicky "Grand Piano" patch. I was able to get good balance with the GR-33's global string sensitivity settings adjusted to the lower middle range, and the picking models of patches were reset to "normal". The GR-33 was able to correctly identify the string I was picking far more accurately. This helped immensely with tuning since the note lock-on was so stable-- I used the tuner to adjust my new bridge's intonation.

The piezo acoustic sound is also very cool; the sound is crisper and more defined than my magnetic pickups. I immediately thought "Monte Montgomery". However, the piezos also pick up every nuance, right down to the creaks and thumping of whammy bar usage. The whammy bar is something that's still best done using the magnetic pickups. The output gain is also pretty dramatic. There's a trimmer pot on the circuit board, but difficult to adjust against the magnetic output because you have to have strings and scratchplate on to compare, and that means that you can't access the trimmer pot. No big deal though.

For a competent Do-It-Yourselfer, this is a way-cool and exciting thing. Although I live in a great town to have guitar work done (Austin--home of Dan Erlewine, Eric Johnson, and self-proclaimed "Live Music Capital"), being a cheapskate, I'd be reluctant to pay to have the unit professionally installed, just as I prefer to take care of the adjustment and maintenance of my guitars. I hope this doesn't sound too arrogant or patronizing, but I've realized that some people have that D-I-Y bent and some don't, and that most of us would rather be cheapskates. But in pursuit of being an effective cheapskate, you've got to be realistic about your limitations (to mangle a Dirty Harry Zen-ism).

My only gripe with the Graphtech kit is that the manuals aren't quite as good as I'd initially thought. The connections aspect isn't especially difficult or complex. The manuals do give you the broad view of the system, but some of the particulars can seem unclear or frustrating, especially since the system is split between the acoustic preamp and Hexpander modules, with separate manuals for each. There's some overlap in the material, and while they do a good job of bridging them, they don't do an excellent job. The manuals don't have much in the way of technical detail and some of the pin diagrams seem deliberately and unnecessarily vague (" an artistic representation only, not a schematic..." --okay then, where's the schematic?). You shouldn't have to refer to the same basic diagram in two manuals to figure out what specific pins are for and what color the wires should be so you can extrapolate their general wiring philosophy. I would have appreciated the pin diagrams detailed with a conventional schematic representation of potentiometers and switches so you knew which pin connected to the pot's wiper arm, for example. That kind of stuff is often in a manual's appendix and saves time lost by figuring it out yourself. My suspicion is that they're deliberately vague about this to show how easy it is and to nudge folks in the direction of buying their prewired controls. This is understandable but seems a little odd since many of their ideal target audience (I suppose)-- folks who are basically conversant in electronics and confident enough to undertake the project-- would recognize the omissions and only be inconvenienced by them. In my opinion, products sold in a kit form should provide as much information as possible to assist in successful assembly and troubleshooting. The "just enough information" philosophy and providing mainly artistic representations can create a false sense of confidence regarding the ease of overall assembly by reducing it to something analogous to simple button pressing. Knowing which buttons to press can often get the job done, but is practically worthless when one encounters problems or needs a custom solution. I suppose this may help sell the product to a broader audience, but it's a little misleading: There's much more to installing the system than just plugging in the connectors as shown in the pictures.

(That seems kind of harsh, so to avoid creating the wrong impression let me state that I have the utmost respect for Graphtech, their product, and their business practices. They've been wonderful to deal with. I believe that their manuals reflect the inherent conflicts in trying to position a product like this for sale to the general public. We're not quite there yet, but very close-- read my last paragraph.)

After completing my installation, RMC's position of reluctant sales to the public (as I perceive it) is understandable. I'm fairly competent with my hands and tools, and know enough about electronics to deal with stuff like this; but I didn't find the job to be a 10-minute walk in the park. Given that not everyone who might be interested in a piezo/13-pin system has those qualifications, it would be misleading to present the installation job as simple and easy. While the wiring is greatly simplified by using plug-in connectors, that's only a small part of the whole job- it's a combination of that, woodworking and shoehorning. There's more to the differences between guitars than just the construction of the bridge, and the prospective installer should be able to improvise and tailor the solution to the specific guitar. I suspect that for many people, the installation job would be best left to a professional luthier or a friend who's handy with this sort of thing. If you plan to have it professionally installed, it might be worthwhile or perhaps cheaper to ask a Luthier-- he might be able to get a better total price on an RMC system than you paying full retail price for a kit and paying him to install it. Graphtech does recommend professional installation, but they're willing to give you the rope to hang yourself if you overestimate your competence and choose to do it yourself. And if you do that, you'll get no sympathy or compassion for the damage you might do: It could cost you dearly.

The emergence of this type of product creates an obvious market for another product: Various body styles finished in custom colors, predrilled and routed for 13-pin systems and battery boxes. That would vastly simplify installation and truly broaden the Do-It-Yourself appeal of this product. This would also allow a reversible modification on a treasured guitar... but you have to wonder: At what point is it still the same guitar, and could it still be called a "Fender Stratocaster"? Gee... maybe Fender should produce a piezo/13-pin Strat?


What Does It Sound Like? MP3 Sample (800k) This is a short rough & tumble recording (through a camcorder) of a few synth sounds. The first sample is a Rory Gallagher ragtime guitar snippet using the GR-33's Grand Piano patch. It's a flatpicking/2nd & 3rd fingerpicking thing that tracked pretty well, considering my tenuous grasp on the technique. The second sample is just a generic jazz trumpet riff; The synthesizer's natural instrument sounds seem to encourage you to play familiar, generic-sounding riffs that might be appropriate for the natural instrument. The third sample is a very synthesizer-ish sound; I think that kind of sound was originally an attempt to capture the sound of a distorted electric guitar for keyboards, so all it comes full circle. (Ummmm...Ignore the odd pauses.)

The non-synthesizer blooz thing at the end has nothing to do with the Hexpander, but shows off a couple of new/old toys: a Roland Jam Station (which has the patience to accommodate my endless noodling) and a Pod-xt (which produces a bunch of nice distorto & clean tones with kewl stompbox effects). For mindless noodling, I prefer the standard guitar feel and sound because you can get as raunchy & raucous as you want: The synthesizer demands better manners. But the synthesizer extends the guitar's possibilities immensely-- sort of like a superduper effects box that opens the portal to the huge world of MIDI.