<P> It's unfair to criticize a 22 - year - old for adapting with the times, though, especially considering the sound in question is merely one part of a precision - built machine that is' I Knew You Were Trouble' . After all, Swift is the pop moment, and the ways in which she and her peers adapt new sounds and vibes into their work is the lifeblood of pop innovation . Even if the bass drop in question is a conceit--it's not like the song is going to be a hit among dudes rocking to Rusko--the Max Martin / Shellback collaboration is made better by the bass (as is usually the case). </P> <P> It's for that reason that Swift's use of it has prompted so much discussion . Pop has been sonically conservative for the past half - decade (at least). Any hint at evolution or surprise from the upper echelons of the charts is a welcome development . And even if said surprise is little and relatively inconsequential, it serves as a reminder of pop's fluidity . </P> <P> MTV News' Jocelyn Vena described the track as "chaotic", commenting on how "the song touches on all genres of music, with moments of straight - up Top 40 pop, country and even dance, with its grinding effects, especially on the bumping chorus ." Sam Lansky from Idolator was conflicted but hopeful about the departure from Swift's typical sound, remarking that "the hook isn't quite as immediate as' We Are Never Ever Getting Back Together', but Martin's stamp is still all over' Trouble', from the bright, sparkly instrumentation to the keen, radio - friendly melody . There might be a little part of us that misses Swift's very personal and idiosyncratic songcraft, but it's already clear that it's elsewhere on the album--and the introduction of these all - star producers into the mix is giving Swift a chance to show that she's way more versatile than just a girl with a guitar ." Chris Wilman from The Hollywood Reporter dubbed the song as a "great rock & roll song--and an emotional one, though the ear candy elements disguise that at first ." Allison Stewart from The Washington Post gave a negative review of the song and its production, saying that "(Max Martin) and partner Shellback infect' I Knew You Were Trouble' with a wobble right out of Hot Topic's dubstep department . It's gratuitous and weird, done for the sake of saying you did it, and so tentative they might not have bothered ." Amanda Dobbins from New York felt that the dubstep inclusion in the song was minimal and described the song as "yet another plucky, vowel - laden Taylor Swift breakup jam!" James Reed from The Boston Globe compared the song and another track from Red called "22", saying that they "vaguely make Swift sound like she's Katy Perry approximating Joan Jett". </P> <P> Prior to its release as a promotional single on October 9, 2012, the song debuted at number three on Billboard Hot 100 and number one on Hot Digital Songs with 416,000 copies sold in its first week, Swift's second largest first week singles sales . It became Swift's 14th top ten hit and her 11th song to debut inside the top ten and also her second to chart at number one . After the song debuted in the top ten and became Swift's fourth top ten hit from the album, Swift became one of the few artists with 3 consecutive albums that all included 4 top ten hits . With sales of 416,000 from "I Knew You Were Trouble", Swift became the first artist in digital history to have two songs that debuted with sales of 400,000 or more copies . It also gave Swift two songs in the top five for the first time in her career when "We Are Never Ever Getting Back Together" held at number five on that week . On November 27, 2012, the song was released as the second pop single from Red . It is Swift's second album single not to be released on country, following "The Story of Us". The song bounced back at the top ten and during the chart week of December 30, 2012 and three weeks later, after the song sold 582,000 copies, it reached its new peak at number two, being blocked by Bruno Mars' "Locked Out of Heaven" from the top spot, and tying the song with her previous released singles, "You Belong with Me" (2009), and "Today Was a Fairytale" (2010) as her second highest charting song on the chart . This became the fourth best single - week digital sales of all time and second best for a track not in its debut frame . The song was certified 5x Platinum by the RIAA in December 2013; as of November 2014, it has sold 5 million copies in the United States . </P>

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