How to Use Arpeggios in Guitar Solos
A short triad arpeggio (see [[chord-tones-melodic-solo-secret:the article on arpeggios]]) is only the start. Real chords in songs often contain a fourth note, the seventh, and an arpeggio built with it sounds noticeably more mature than one built from a plain triad.
A seventh chord is a triad plus one note
A seventh chord (dominant, minor, or major - see the article on intervals) is the same three triad notes plus a fourth, the seventh. An arpeggio over that chord is physically no harder than a triad arpeggio - it's just one note longer.
The seventh gives a pull that a triad lacks
A seventh almost always sounds like a note that 'wants' to resolve into a neighboring degree of the next chord - that pull is exactly what gives a seventh-chord arpeggio a sense of forward motion a more static triad doesn't have. It's especially noticeable on dominant seventh chords in blues.
An arpeggio doesn't have to run strictly in order
You don't have to play the arpeggio's notes straight from bottom to top - skipping a note, starting from the third instead of the root, or a short step back makes the arpeggio feel like a phrase (see the article on building phrases) rather than a mechanical drill.
Find the arpeggio inside positions you already know
There's no need to learn a whole separate shape for the arpeggio - the seventh chord's four notes already sit inside a familiar CAGED and pentatonic position (see the article on connecting CAGED, triads, and the pentatonic), you just need to learn to pick them out from the rest of the position's notes.
Drill: an arpeggio on every chord change in a progression
Take a progression with at least one seventh chord, and on every change play a short arpeggio of exactly the current chord before returning to the regular scale - same principle as with triads, just with a fourth note added.
Try it in practice
Open chord trainer