A fine example of an everyday item that can be improved through the use of materials engineering is a standard guitar. Classically, guitars were composed of wooden bodies accompanied by nylon or bronze strings, for classical guitars and standard guitars respectively. These wooden bodies can be greatly affected by heat, humidity, and water. Through the use of engineered materials, guitars can now be created to fight the effects of humidity and moisture. Instead of wood, the entire guitar can be composed with a carbon fiber-reinforced composite. Polyester can be added to the soundboard during processing in order to get the desired tuning. Depending on the sound frequency and style of guitar, the strings are composed of nylon or bronze alloy. The bronze alloy for guitar strings is generally around an 80/20 copper/aluminum alloy. For an electric acoustic guitar, a piezoelectric transducer can be placed on the side of the guitar. The transducer converts sound vibrations to an electric signal, which can then be sent to an amplifier and broadcast over speakers.