Iron Maiden's self-titled album is an undisputed heavy metal classic -- one of the great debut albums in history. And the band continues to perform tracks like "Running Free," "Iron Maiden" and "Phantom of the Opera" live despite original vocalist Paul Di'Anno having left the band over three decades ago. However, Maiden singer Bruce Dickinson not only claims the album "sounded like a sack of s--t," but that bassist / creative mastermind Steve Harris "hates that record."

Speaking with Spin about Iron Maiden's original sound, Bruce Dickinson distanced Maiden from the "punk rock" label attributed to Iron Maiden and Killers. "If you look at all the old Steve Harris interviews -- he hates punk rock," says Dickinson. "The first Maiden album sounded punky because it sounded like a sack of s–t. He hates that record. The first singer gave it a little bit of that kind of vibe, but the punk thing was nailed to the band by the press. The band absolutely hated it, because there was no way on God’s green earth Maiden were ever, even remotely, a punk band."

To be fair, Dickinson is referring to the production quality of Iron Maiden rather than the songwriting. Looking back at Killers, Bruce describes the record as a complete departure from anything that could have possibly resembled punk rock, "As soon as Killers came out, which was a proper sounding record, it was obvious -- where’s the punk thing on Killers? You’ve got 'Murders in the Rue Mourge' which basically could have been off of Deep Purple’s In Rock, you’ve got 'Prodigal Son,' a proggy, sweet little ballad, you’ve got 'Twilight Zone,' all this kind of stuff -- where’s the punk thing? Don’t get it."

Iron Maiden's 16th studio album, The Book of Souls, hit No. 4 on the Billboard 200 chart, moving 74,000 units in its first week. The Book of Souls also hit No. 1 in at least 23 countries, including Maiden's homeland of the U.K.

See the Yearbook Photos of Bruce Dickinson + Other Rock Stars

Is 'The Book of Souls' Iron Maiden's Final Album?