Tony Iommi's guitar riff at the beginning of Black Sabbath's song Paranoid is one of the most famous riffs of all time. Even though its only played four times and not repeated during the rest of the song, its simple melody is easy to remember and starts the song with a suitable driving rhythm. From the minute the riff begins it captures your attention and the overall dynamics are increased with the introduction of the drums and bass.

During the verses, the main rhythmic element played on the guitar is a chugging power chord sequence that uses the palm muted power chord, so often found in heavy rock music. Ozzy Osborne's cutting vocals take precedence during the verses, forming (other than the guitar riff intro) the most memorable parts of the song. In this aspect, Paranoid has a more unusual structure in that the verses act as the hook instead of the chorus.

The three-chord break that divides the verses leaves the chugging rhythm momentarily, acting like a short breather in between the frantic rhythm of the verse. By the second break the sequence varies slightly with lyrics added, forming the bridge, "Can you help me? Thought you were my friend" etc. Using chords that ring out over the pounding rhythm of the verse helps to add some definition to the separate parts in the song. Greater emphasis is also now felt when the chugging rhythm is resumed.

In true rock fashion the guitar solo is long and uses virtually every trick in the book. Based mostly around the pentatonic minor scale, the lead is double tracked and unusually, both lead tracks are not the same. In places the two lead guitars differ greatly from each other adding a swirling psychedelic mixture of twisting lead guitar lines that suit the lyrical subject perfectly. Tony's playing has a fluid feel yet continues in the frantic nature of the rest of the song. His sense of timing and dynamics are great with the solo building lyrically to a peak and ending without anything left to say. What is particularly notable is that you can actually hum back to your self the majority of the solo after only a few listens. This makes the solo a great asset to the song as it can also be considered an added hook.

What can we learn?

• Memorable yet simple guitar intro.
• Driving muted guitar rhythm accompanies the verses vocal hooks.
• Bridge momentarily drops the driving rhythm to create a breather
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• Solo uses timing and dynamics to build a memorable, singable tune.