In an acoustic instrument, the body of the guitar is a major determinant of the overall sound quality. The guitar top, or soundboard, is a finely crafted and engineered element made of tonewoods such as spruce and red cedar. This thin piece of wood, often only 2 or 3 mm thick, is strengthened by differing types of internal bracing. Many luthiers consider the top the dominant factor in determining the sound quality. The majority of the instrument's sound is heard through the vibration of the guitar top as the energy of the vibrating strings is transferred to it. The body of an acoustic guitar has a sound hole through which sound projects. The sound hole is usually a round hole in the top of the guitar under the strings. Air inside the body vibrates as the guitar top and body is vibrated by the strings, and the response of the air cavity at different frequencies is characterized, like the rest of the guitar body, by a number of resonance modes at which it responds more strongly.
"With a note of music, one strikes the fundamental, and, in addition to the root note, other notes are generated: these are the harmonic series.... As one fundamental note contains within it other notes in the octave, two fundamentals produce a remarkable array of harmonics, and the number of possible combinations between all the notes increases phenomenally. With a triad, affairs stand a good chance of getting severely out of hand."
Russell, George (2001) . "Chapter 1 The Lydian scale: The seminal source of the principal of tonal gravity". George Russell's Lydian chromatic concept of tonal organization. Volume One: The art and science of tonal gravity (Fourth (Second printing, corrected, 2008) ed.). Brookline, Massachusetts: Concept Publishing Company. pp. 1–9. ISBN 0-9703739-0-2.
An open tuning allows a chord to be played by strumming the strings when "open", or while fretting no strings. The base chord consists of at least three notes and may include all the strings or a subset. The tuning is named for the base chord when played open, typically a major triad, and each major-triad can be played by barring exactly one fret. Open tunings are common in blues and folk music, and they are used in the playing of slide and lap-slide ("Hawaiian") guitars. Ry Cooder uses open tunings when he plays slide guitar.
The Guitar Program at Musicians Institute is designed to develop professional level technique and musicianship through performance-intensive and immersive experiences. Guitar classes are taught by leading professionals and students will get trained in the basics of guitar playing, including performance, ear training, melodic soloing along a huge variety of contemporary styles.