Here's an accurate simulation of the classic Van Halen sound from their debut album:

AMP: Metal (green)

DRIVE: 7

BASS: 4

MID: 6

TREBLE:8

VOLUME: 8

FX2: Phaser

ROUTING: Pre

SPEED: 0.2

FEEDBACK: 50%

MIX: 50%

FX3: Digital delay

ROUTING: Post

TIME: 250ms

FEEDBACK: 30%

BASS: 50%

TREBLE: 50%

MIX: 30%

REVERB: Vintage plate

ROUTING: Post

PREDELAY: 50%

DECAY: 50%

TONE: 50%

MIX: 60%

Using a strat with a humbucker at the bridge and vintage tremolo will get the best results.

Enjoy!

Dario.