The contemporary guitarist is destined to encounter performance situations in which amplification is necessary—from the vast majority of orchestral concerti to TV and radio shows, in addition to less formal (but equally lucrative!) settings such as weddings and background-music gigs. Fortunately, technology has improved considerably in the past dozen years or so, leading to a variety of viable choices that will enable you both to be heard and to be proud of the sound you’re producing. Let’s look at some of the options on the table, starting with some of the most popular internally mounted amplification solutions.
The first choice to make is whether to use a dedicated guitar for plugged-in performances, or to have only one instrument. In this latter case, and especially when dealing with expensive concert guitars, the installation of any internal pickup must be weighed against its impact on resale value (guitarists and collectors are after all a picky bunch) as well as any effect on acoustic/unplugged tone.
I’m afraid I’m not the biggest fan of undersaddle (piezo) pickups for a number of reasons. Through the years, I’ve found that installing anything under the saddle runs the risk of altering a guitar’s tonal response. In addition, the vast majority of piezo pickups are designed to work with preamps installed inside the guitar. This requirement is an additional deal-breaker for me, as I have found that even the lowest-profile preamps, with their batteries and dangling wires, adversely affect an instrument’s resonance and responsiveness. To top it off, most (but not all) piezos produce somewhat of a compressed and “quacky” sound which is a far cry from the natural tone of the classical guitar.
To their credit, piezos are relatively feedback resistant, and their tone can be greatly enhanced by digital modeling systems such as the Fishman Aura and D-TAR Mama Bear: in this light, a dedicated stage guitar with a newer-generation undersaddle piezo pickup can be a satisfactory plugged in solution for anyone but the most demanding of tone freaks. As an added bonus, piezos work great in solid body, nylon-string guitars, yielding a serviceable “gigging” instrument that is almost completely impervious to feedback.
A Less Invasive Option
Soundboard Transducers (SBTs) are a family of pickups which are also installed inside the guitar—but they are attached to a brace or to the underside of the bridgeplate. In comparison to undersaddle pickups, they offer a more natural sound at the expense of an increased sensitivity to feedback. SBTs can be either active (with an internal preamp and batteries) or passive—these latter ones should be plugged into an external preamp using a cord no more than three feet long. SBT installations, when done well, leave the guitar almost unscathed except for the addition of an endpin jack—the transducers are negligibly light, and the lone wire can be run along the side of the instrument—thus offering a reasonable solution with regards to their effect on value and unplugged tone. Companies like K&K and McIntyre produce extremely natural-sounding and reliable SBTs.
One final word about preamplification: there is a saying that goes “your amplified guitar sound is only as good as the weakest link in your signal chain.” Choosing a clean, quiet, and powerful preamp is as important a step as the choice of a pickup system. Passive pickups in particular require extremely high input impedances (generally greater than 1MOhm, sometimes as much as 10MOhm). There are several excellent commercial choices to be had; I recommend looking for preamps that offer variable input impedances and a flexible EQ section—“sweepable” or parametric midrange controls are especially useful. We’ll talk more about EQ and other amplification solutions, including removable and external ones, in the next installments of the series.
Image by JimK