A block chord is a type of musical chord voicing where all the notes of the chord are played simultaneously, as opposed to being arpeggiated or broken. This simultaneous attack creates a dense, unified sound. Block chords are often, though not exclusively, arranged in close position, meaning the notes are kept within the span of an octave, which contributes to their characteristic solidity.
In musical composition and performance, block chords serve several purposes:
- Harmonic Emphasis: They clearly delineate a specific harmony, making its presence immediately apparent.
- Rhythmic Solidity: When multiple instruments or voices play block chords in unison or parallel motion, it creates a strong rhythmic and harmonic foundation.
- Textural Density: They contribute to a full, rich musical texture, often used in homophonic settings where a melody is supported by accompanying chords moving in the same rhythm.
Applications and Contexts:
- Classical Music: Block chords are fundamental in many classical genres. They are characteristic of chorale style (e.g., Bach's four-part chorales), hymn tunes, and much of the homophonic writing in orchestral and chamber music where sections or instruments play chords in rhythmic synchronization.
- Jazz Music: Block chords are particularly prominent in jazz, especially in piano playing and big band arranging.
- Piano: The "locked hands" or "block chord style" (also known as "Shearing voicing" after George Shearing, or earlier by Milt Buckner) is a specific technique where the right hand plays the melody harmonized by a chord, and the left hand plays the same melody an octave lower, also harmonized by a chord, often with the top notes of both hands doubling the melody. This creates a thick, harmonized melodic line. Block chords are also essential for comping (accompanying) and soloing.
- Big Band Arranging: In jazz big bands, sections like the brass or saxophones often play block chords together, creating powerful and cohesive harmonic statements that drive the ensemble's sound.
- Contemporary Music: Block chords remain a staple across various contemporary styles, used for harmonic grounding, dramatic impact, or to create specific textural qualities.
The term "block chord" primarily refers to the manner of articulation (simultaneous) and the voicing (often close-position, creating a unified block of sound), distinguishing it from other chordal treatments like arpeggios or broken chords where notes are played successively.