Using the wood of an instrument as a sensor with electrodes strategically applied to its baseboard, this novel technology from Georgia Tech enhances sound quality and clarity by picking up electrical waves that propagate within the wood itself in amplified acoustical instruments. This innovation is designed to overcome the struggles of the music industry to capture and amplify the unique sounds and subtle frequencies that are a direct result of the wood quality and craftsmanship of acoustical stringed instruments.
- Enhanced clarity: Captures electrical signals and vibrations with electrodes applied to “hotspots” on the instrument to reveal the subtle frequencies inherent in the wood and craftsmanship
- Improved sound quality: Leverages both captured vibrations and piezoelectric waves to enhance the instrument’s sound
- Low cost: Uses readily available electrodes and other electronics to leverage the inherent properties of the wood
- Acoustical stringed instruments made of wood, such as guitars, violins, cellos, and others
- Structural monitoring, such as detecting the health of trees in a forest or examining the stability of wood structures
In modern acoustic instruments that have amplified sound, a piece of piezoelectric material is used as a microphone and is connected to a speaker or recording device. This conventional amplification does not, however, pick up the subtle frequencies that originate from the quality of the instrument itself.
How It Works
Atomically, wood possesses the characteristics of crystals or bodies with regular structure such that the particles composing them are distributed according to the law of space lattices. This means the wood has piezoelectric properties, and it is possible to pick up electrical signals when stress is placed on the wood (e.g., when playing the instrument).
With Georgia Tech’s method, the wood is used as its own sensor. For example, in guitars, stress concentrates in six locations across the baseboard. Electrodes can be applied to the underside and topside of a pre-lacquered guitar so they have good contact with the wood and can pick-up the vibrations and any piezoelectric waves that appear when the instrument is played. These electrical signals generated from the stress contribute to the enhanced sounds of the guitar.
An auxiliary port connected to speakers or a recording device is placed outside of the guitar, and additional electronics translate the signals into audio.