Detail the application of arpeggios in sweep picking techniques to create complex and flowing lead lines in progressive metal.

In progressive metal, the combination of arpeggios and sweep picking is a cornerstone technique for crafting complex, fluid, and technically impressive lead lines. This approach allows guitarists to create melodic passages that span wide intervals and move with great speed and precision. Arpeggios, which are broken chords played one note at a time, provide the harmonic framework for these lead lines, while sweep picking, a technique that involves a continuous, fluid motion of the pick across the strings, allows for the rapid execution of these arpeggiated figures. Together, they create the soaring, intricate melodies that define the genre.

The application of arpeggios in sweep picking in progressive metal is diverse, often involving extended chords such as major 7ths, minor 7ths, dominant 7ths, and alterations like 9ths and 13ths. These complex chord types provide a rich harmonic palette for lead lines, enabling the guitarist to create melodies that are not only technically impressive but also harmonically engaging. For example, a guitarist might sweep pick through a Cmaj7 arpeggio (C-E-G-B), ascending and then descending through the different positions on the fretboard. This technique isn’t just a linear execution; instead it is often used to create musical phrases. This allows for the creation of musical phrases that are not just scalar runs, but harmonic movement through the fretboard.

Sweep picking is crucial for executing these arpeggios with speed and fluidity. Instead of picking each string individually, a sweep picking motion uses a single downstroke or upstroke to move through a series of adjacent strings. This reduces the amount of picking, making it possible to play arpeggios at much higher speeds. A common example is a sweeping pattern on a four-string arpeggio. A single downstroke across the lower strings and a single upstroke on the higher strings. This creates a continuous and flowing feel to the phrase. Often a technique called economy picking is combined with the sweeps. Economy picking involves changing directions with the picking hand only when it is needed. The player will use either an upward or downward pick stroke that is convenient and the most efficient for the hand. This combined technique creates a faster and more fluid sweep.

Complex phrases are often created using multiple sweeping arpeggios and are not always straight sequences. The guitarists may switch between different arpeggios and rhythmic variations, such as adding a tapped note or a hammer-on in the middle of the sweep picking to add texture and complexity to the line. A progressive metal guitarist might alternate between sweep picking a C minor 7 arpeggio, a G major 7 arpeggio, and a D diminished arpeggio in rapid succession, creating a harmonic sequence that spans a wide range of the fretboard. These lines don’t always follow patterns and are usually created to best suit the sound the song requires. This constant interplay between different arpeggios is a technique that pushes the boundaries of the instrument.

In terms of musicality, sweep-picked arpeggios provide the foundation for long, flowing melodic phrases that can create a sense of grandeur and epic scale. The seamless transitions between arpeggios allow the lead line to weave in and out of the harmonic backdrop and can create a very large and impressive sound. For instance, during a progressive metal bridge section, a sweep-picked arpeggio melody might transition seamlessly through a series of chords, creating a sense of harmonic motion. This allows the line to take the listener on a journey that goes through a series of different musical landscapes. In essence, the use of arpeggios in sweep picking in progressive metal is not just about technical display; it’s about creating an intricate and engaging musical experience that integrates technique and musical ideas.