"Eruption" is an instrumental rock guitar solo performed by Eddie Van Halen. It is widely considered one of the greatest guitar solos of all time. It segues into "You Really Got Me" on the album Van Halen, and the two songs are often played together by radio stations. The song was also released as the b-side to the "Runnin' with the Devil" single.

"Eruption" starts with a short accompanied intro with Alex Van Halen on drums and Michael Anthony on bass. The highlight of the solo is the use of two-handed tapping. "Eruption" was played on the Frankenstrat, with a MXR Phase 90, an Echoplex, a Univox echo unit and a 1968 Marshall 1959 Super Lead tube amp. The Sunset Sound studio reverb room was also used to add reverb. The Frankenstrat was tuned down a half-step. "Eruption" begins in the key of A flat and ends on an E flat note that is a twelfth fret, 6th string harmonic processed through a Univox EC-80 echo unit.

The "Eruption" introduction is based on the "Let Me Swim" introduction by Cactus. After the intro, an E-flat major quotation of the "Etude No. 2" by Rodolphe Kreutzer is heard. The end section begins with a series of rapid two-handed tapping triads that have a classical like structure and eventually finishes with a repeated classical cadence followed by sound effects generated by a Univox EC-80 echo unit.

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