Acoustic Amplification: When and How to Plug In
Posted by Robinson Earle on Jul 9th 2019
Acoustic Amplification: When and How to Plug In
At some point in every acoustic guitarist’s journey (these days, often immediately), they will start weighing amplification options. Although we may have been attracted to the instrument due to its intimacy, our current cultural context begs that it be rendered louder. Suddenly, we’re confronted with a myriad of “pickup” options that confound the acoustic guitar’s original immediacy. We’re forced to drill, clutter, and affix. We must choose between microphones, transducers, and magnetic pole pieces, and the combination and placement of each are pivotal. Even after all that, many of us still require a full PA and monitor rig to get close enough to the sound that we hear when picking in our living rooms. Hopefully, this blog will provide some insights that will help you decide on the right gear for your needs.
Basically, it’s a spectrum that ranges from feedback resistance to tonal transparency. On one end, we have the external microphone, on the other end, the magnetic pickup (as in an electric guitar). Although the microphone might seem like the natural choice for purists, its limitations are significant enough that many players gravitate towards transducers (more on them later). First off, even in ideal circumstances, it’s probably not going to sound like your favorite record. Studio and stage microphones are usually designed and utilized with different ends in mind. Hypothetically, one could build a little microphone cage on-stage, prepare a mix with an engineer, and then immerse yourself in good head-phones for the entirety of a performance, but for most of us, this isn’t practical or desirable. Secondly, in order to properly wield an external microphone on-stage, you’ll need to be more-or-less stationary with your instrument. Most acoustic guitarists I know don’t like to be static while performing. Music makes you move. It’s physics. Lastly, microphones are definitely the most feedback prone. One slight shift and you may set that venue a-howl. There are clip-on gooseneck mics that allow more freedom of movement and internal microphones more still, but the former entails much delicacy and the latter differs in output in that it amplifies the inside of your guitar, whereas we’re accustomed to appreciating the way it sounds on the other side of the soundhole.
Transducers, Piezos, etc. are little nodes or strips that translate the precise vibrations of your instrument into audible sound-waves. They can be placed on the bridge-plate, soundboard, or under/inside the saddle. When positioned correctly for a specific instrument, they can offer a startlingly accurate representation of your guitar’s true tone. Many would say that they lack a certain “airiness”, however, which has prompted many manufacturers to combine them with internal microphones and/or preamps with specific EQ curves.
Naturally, the pickup option that offers the most feedback resistance is the one that most resembles that of an electric guitar. Soundhole pickups are either temporarily or semi-permanently set across the soundhole with magnetic pole pieces positioned behind each string. They differ from actual electric sing-coils and humbuckers in that they are specifically calibrated for acoustic strings and tone, but it’s the same general principle. You’re getting less of the body of the instrument, but that also means that there’s less potential for rogue soundwaves to start bouncing around in there. For folks playing acoustic guitar in loud rock contexts, a soundhole pickup with or without transducer and/or microphonic coloring is the best option for actually cutting through.
It can be a process as unique and investigative as finding your acoustic in the first place, but through patience and self-reflection, you will be able to find the right combination for your sonic needs. That said, sometimes the solution for certain players is to just embrace a fully electric guitar. If your band includes other loud electric instruments, a drum kit, and really likes to rock out, it’s likely that your humble six-string will be drowned out. In this case, I would recommend a telecaster or a semi-hollow 335-style guitar. These are electric guitar models that offer enough woody authenticity to carry acoustic-ish picking. Flip to the neck pickup, roll off all the tone, and then slowly pull it back up until it just pokes its head above water, and you’re in business. Look for an amp with clean headroom and don’t be afraid of effects pedals that can offer a different kind of dynamic texture that may make you miss your beloved log cabin of wood and wireless. Besides, it can still be your home. If you write and practice on an acoustic, your electric will play like butter.