To Drill Or Not To Drill
One big headache of customized guitar electronics is where to put the controls. Whether you are adding new pickup options on a solid-body electric or installing a saddle pickup and preamp on an acoustic, the dreaded decision of what to cut and where to drill always looms large.
Gear-heads not afraid to tear into their guitar's electronics are already familiar with the huge number of wiring options available in any electric guitar with two or more pickups, so let's begin with the do's and don'ts of solid-body guitar modification.
One lesson I've learned is never to drill, enlarge or screw when you can use existing controls, parts and cavities. For example, if you wish to add some new pickup options to a Strat or Tele, begin with the pickups you already have. Using a four-pole, five-position switch you can literally double your pickup combinations without structurally modifying your guitar at all. The new switch will retrofit exactly where the old switch went, and the switching combinations are numerous.
Another real "face-saver" for guitar electronics is the push-pull control pot. It looks and functions as a normal potentiometer, but has a double-pole, double-throw switch built into it, which is activated when you pull up on the knob. Click! New sound, no new holes! And speaking of knobs, look for functions that you rarely use and replace them with something more interesting. For instance, Strats can easily do without two-tone knobs. Wire the first knob as a universal tone control and use the second knob for an independent pickup volume, phase switch, or series-parallel switch.
Likewise, Les Pauls can be reconfigured with a master volume and master tone control. A five position rotary switch such as those found on Paul Reed Smith guitars can go in the old switch cavity, and you still have two unused knobs to access your favorite tonal aberrations.
Another important lesson I've learned about guitar wiring is to buy new parts and save the old ones. For one thing, soldering and re-soldering takes its toll on delicate components. A volume pot will only bake so long before it's little resistance strip ceases to resist, and I've seen more warped and useless switches due to over-soldering than I care to relate. For another thing, you never know what might become collectible in 20 years. There are quite a few repair shops currently paying their rent with old Fender Jaguars and Mustangs in need of restoration because 20 years ago some innocent rock 'n? roller tossed out the bridge position pickup in favor of a high-output humbucker. Remove the original parts, stick them in a Baggie with a little masking-tape label, and save yourself some grief, and some cash, later on.
This applies to pickguards, too. A new pickguard in a cool retro color or a wild magic-marker make-up job is far better than an original pickguard with a couple of extra holes drilled in it. A new pickguard also gives you the opportunity to reposition knobs a bit for a custom feel. I own several Strat clones, all of which have the volume knob set a little further away from the bridge pickup, thanks to new pickguards.
One more bit of advice: there is virtually no reason to take a pickup apart to get at the coil (or coils). The cost of an identical pickup with appropriate coil taps is always less than the headache of trying to do it yourself. If for some reason you simply must have one particular pickup modified with a coil tap, send it to one of the big boys of pickupology. The cost is usually very reasonable (about the cost of a new pickup) and you'll have the satisfaction of knowing it will be done right.
To Drill Or Not To Drill, Part 2 - Acoustics
Acoustic guitars have become as important to amplified music as their fully electric counterparts. In fact, anyone with a bit of common sense and experience will know that an amplified acoustic guitar is more of a "signifier" than a unique sonic tool. In other words, when a performing artist puts down their electric axe and picks up their acoustic, it tells the audience to expect something of the "unplugged" variety and perhaps a bit of a downshift in the energy level of the performance. The exact same sound could be achieved with a solid-body electric and a piezo pickup system such as the Mike Christian Saddle Pickups or the Fishman Powerbridge, but the visual message would be lost.
By the same token, musicians as diverse as Ani DiFranco, Adrian Legg, and Michael Hedges have used the acoustic guitar in a manner so removed from it's intended function that it could also just as easily be a solid-body electric but, again, the visual message of where these artists are "coming from" would be lost. We listen with our eyes as much as our ears, and maybe a little more.
Even with a revolution in audience awareness, there remains the fact that the physical shape and response of the instrument will tend to elicit a certain kind of performance. The bottom line is that holes will be drilled and pickups installed in acoustic guitars for the foreseeable future, so let's see if we can make some wise choices about when guitars should be sliced into for the sake of greater amplification.
The prime candidate for acoustic-electric amplification is the guitar pre-designed for amplification. Ovation's shallow-body guitars and Gibson's Chet Atkins models are two examples which come to mind. For the player who wants to wrap their arms around something big, virtually every major manufacturer offers a full-bodied model with pre-installed saddle pickups and on-board electronics. Some very nice electrified acoustics can be found in the $500 price range, and this is the first place one might look before hacking away at a valuable instrument.
But let's just say that your budget is limited, or you just love the feel of your current acoustic axe. What are some of the pickup options available, and what kind of surgery will be needed to pump up the volume?
The most non-invasive solution for acoustic amplification is the soundhole pickup. It functions very much like an electric guitar's pickup in that it senses the magnetic vibrations from the string at the soundhole. It usually slides into or clips onto the soundhole area with no modification to the instrument. Of course something must be done with the wire to the amp, and a common temporary cure is to tape it to the face of the guitar. If you choose to do this, keep in mind that sooner or later that tape will get gooey, collect dirt, get on your fingers, and maybe even react with the guitar's finish. And don't even think about stepping on the wire.
The best solution for pickup wires on an acoustic guitar is to install an endpin jack. Just like it sounds, this doubles as an endpin for your strap and an output jack for your pickup. Installing one of these with a soundhole pickup means that you're making a semi-permanent commitment to that pickup, since it requires cutting the pickup cable to the appropriate length inside your guitar. The modification to your instrument is minimal: The original endpin is removed, a hole just under 1/2" is drilled through the endblock at the location of the original hole and the new jack installed.
The next step in acoustic amplification, and a big step towards authentic acoustic tone, is installing a bridge saddle pickup. This is a tiny little device, which sits beneath your current saddle and transmits the saddle's vibrations to your amplification of choice. It has a tiny little wire attached to it which requires drilling a tiny little hole (usually about 3/32" in diameter) from the saddle slot through the top and bridge plate into the inside of the guitar. The signal exits via an endpin jack. Once again, invasion to the instrument is minimal.
Most serious players want an on-board preamp for their bridge saddle systems. The increase in tonal quality is significant and the instantly accessible control over volume and tone is often the saving grace on a fidelity-challenged gig. The payback is that now all kinds of bells and whistles must be installed in the guitar's body. Specifically, the preamp and controls must be mounted in an accessible location such as the bass side of the upper bout, which means cutting a little window in the guitar's side. Ouch! Then there's the matter of adding a battery holder, which will either be accessible through the soundhole or via a little hatch on the guitar's side. Ouch! Ouch! This about triples the number of wires running inside the guitar, and these need to be secured, usually with special stick-on clips, to keep them from rattling.
Beyond this, the sky is the limit for acoustic signal sensing. On-board microphones are very useful, as are combinations of mics, saddle transducers, and soundhole pickups. With all of the cutting and drilling that these installations entail, the important factors to weigh are: 1). The inherent value of the guitar before slicing and dicing and 2). The total cost of installing all the gizmos. This kind of work should always be done by an experienced and well-informed luthier, as should the often-needed "uninstallation" which follows a few years later. Balance these factors against the possibility of buying something "off the shelf" which will do the job nearly as well, and chances are you'll be comfortable with your decision to drill or not to drill.