Perhaps no guitarist in metal is more renowned for their use of a wah pedal than Metallica's Kirk Hammett and in a recent interview with Guitar World, the veteran six-stringer opened up on why he loves using this particular effects pedal so much, getting a bit defensive along the way.

Despite being Metallica's lead guitarist for four decades, Hammett's playing comes under constant scrutiny, as does just about every aspect of the band and its individual members. The group is under the microscope like no other, something that just comes with the territory when you're one of the biggest bands to ever step on a stage in music history.

Already this year, the 60-year-old musician has had to defend his solo on the lead 72 Seasons single "Lux Aeterna," poking holes in his detractors' arguments, which garnered an additional response from a YouTuber who wrote his own "improved" solo for that track.

Now, he reveals what he loves most about the wah pedal, a tool that has become as synonymous with his playing as his use of pentatonic scales.

"The wah enables me to mirror the inner voice in my head and in my heart," he explains to Guitar World, "That’s what I’m hearing — all these manipulated notes and tones, because that’s what the human voice is like. We cycle through all these different tones and frequencies when we speak. When I step on that wah pedal and hear that click... well, I’m hearing that clicking in my brain and in my heart at the same time."

In his previous defense of his "Lux Aeterna" solo in an interview with Total Guitar, Hammett mentioned a specific aim he has when crafting his guitar solos. "What’s more appropriate is coming up with melodies that are more like vocal melodies. And guess what? The best scale for mimicking vocal melodies is the pentatonic," he said.

This notion feeds right into his use of the wah pedal, using it to help mirror voice and melody.

Aware of how much he's known to favor the wah, Hammett also tells Guitar World that he "can’t think of anybody who uses the wah pedal as much as I do."

And if you don't like it, well, too bad! That doesn't bother Hammett.

"I don’t care what anyone fuckin’ says. If I feel like stepping on the wah pedal, I step on the fuckin’ wah pedal, because it brings me closer to what I’m hearing internally. And that’s the whole point of gear – to help bring the thing you hear internally out into the external world," the guitarist argues.

READ MORE: Metallica Lawyer Explains Why Band Was Right to Sue Napster Over Illegal Downloading

Back in 2018, Hammett recollected with Metal Hammer the song that inspired him to use the wah pedal in the first place.

"[Jimi] Hendrix wasn’t actually the first person I heard use a wah-wah pedal – that was Brian Robertson from Thin Lizzy! The first time I became aware of it was the song 'Warriors' on Jailbreak," he revealed, "He comes in with this totally wah-ed out two-three notes, and I said to my friend, ‘What is that?!’ He said, ‘That’s a wah-wah pedal.’ ‘Wow, fantastic!’ I made a mental note of that…"

You can catch Kirk Hammett and his beloved wah pedal in action this year and next on Metallica's worldwide M72 tour, which kicks off today (April 27) in Amsterdam. See all scheduled dates here and head to this location to grab your tickets.

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