Longtime Dream Theater keyboardist Jordan Rudess admits to not quite being prepared to perform Metallica songs before his band covered Metallica's Master of Puppets, despite his years of playing classical music.

Listeners can hear Rudess' progressive metal act perform the landmark 1986 thrash LP in full on Master of Puppets – Live in Barcelona, 2002, the tribute set that was reissued last month as part of Dream Theater's new throwback series, the Lost Not Forgotten Archives.

"Wow!" Rudess told Revolver this week when recalling his thoughts ahead of the concert. "The keyboard does not have a guitar pick and playing rapid-fire notes is not that easy. I grew up playing Chopin and Liszt, and even they did not prepare me for Master of Puppets!"

The technical complexities of metal often get compared to the intricacies of classical music. Regardless, transposing from guitar to keys is a big challenge.

"Although I was appointed the job of being the equivalent of a rhythm guitarist for our version," Rudess explained, "I did have some flexibility to change things up a bit and add in some more keyboard-type sounds and parts. Keyboard guitar sounds are not 'cool' right out of the box, so I had to do some serious programming to get the articulations to sound realistic."

For him, Master of Puppets was an "eye-opener," he continued. "Before we covered this album, my Metallica knowledge was not so deep. They were a major influence on the other guys in the band. So diving into this helped me to understand the compositional ideas and techniques that were so influential to [our group]."

Having come up "playing Bach, Liszt and Chopin, the idea of technique and virtuosities had a definite place in my mind," Rudess added. "I have to admit that upon discovering Metallica my perception of technique opened up to other possibilities outside of … classical."

According to its website, the Lost Not Forgotten Archives "will see the virtuosic quintet's long-standing Ytsejam Records catalogue reissued, alongside some brand new additions to this special collectors series. Ytsejam Records previously played host to Dream Theater's official bootleg release collection comprising of live shows, demos and studio outtakes from throughout the band's prolific career."

Last month, Dream Theater postponed a planned North American tour to next year. Their new album, A View From the Top of the World, arrives Oct. 22.

Dream Theater, Lost Not Forgotten Archives: Master of Puppets – Live in Barcelona, 2002

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