Acoustic guitars produce natural tones due to wood combinations, creative design of the bridge and correctly placed bracing. However, the sound of the guitar should reach the audience in a large hall and not drown in the music of other instruments if you are playing with a band. This is where amplification comes into play. There are various kinds of pickups available for amplifying acoustic guitars. The pickup converts the acoustic sound of the guitar into an electric signal to amplify it. Many models of guitars have on-board pickups or preamp systems. But for acoustic guitars which are not equipped with on-board pickups, there are multiple choices. Factors such as removable or permanent, conspicuous or invisible, elaborate or basic and your particular style determine the kind of pickup you need.
Some of the common choices of pickups to amplify acoustic guitars have been discussed here.
Magnetic pickups are non-permanent pickups because they are removable. The magnetic pickup is clamped inside the soundhole of the guitar below the strings. The cable can be allowed to hang out from the soundhole, or it can be taped to the body of the guitar. The magnetic pickup converts the energy produced by string vibrations to electrical signals, thereby producing the amplified electric acoustic tone. Magnetic pickups are suitable for guitarists who like to play at high volumes.
Magnetic pickups come in a plethora of varieties. Many magnetic pickups also have features such as equalization and volume adjustments.
Undersaddle pickups are also known as piezo-electric pickups. This type of pickup is fixed under the bridge saddle of the guitar. Undersaddle pickups are made of piezoelectric crystals which produce a voltage by picking up the vibrations of the strings of the acoustic guitar. The circuit is powered usually by a 9V battery.
Undersaddle pickup provides high feedback resistance which is very useful in concerts. It also gives good results when paired with a preamp to increase volume and EQ.
Soundboard Transducers are sensors which are installed inside the guitar on the bridge plate. They sense the motion of the guitar’s top. Soundboard transducers are more susceptible to feedback as compared to magnetic and under-saddle pickups. Thus, they are suitable for low volume acoustic tones in small venues. SBTs can be paired with preamps to generate higher volumes.
SBTs can be installed using putty, double-sided tape or fabric fastener. Thus, they can be easily removed as well.
Internal microphones are fixed inside the body of the guitar. As a result, they can pick up vibrations from a wider area of the guitar. Internal microphones provide a high-frequency range and increased midrange. The tone reproduced is also more natural. Internal microphones are sensitive to feedback, but they can be adjusted to reduce feedback. They can be paired with a preamp or other kinds of pickup.
Dual Source systems are combinations of two or more different types of pickups. Dual Source system reproduces the tone of an acoustic guitar in greater detail and also allows a high level of flexibility. For example, a magnetic pickup with built-in microphone is a dual-source system.