Who is the greatest rock voice of all-time? That's a debate that has often raged amongst music fans over the years, and during a recent episode of the Always Sunny podcast (heard and seen below) featuring It's Always Sunny in Philadelphia stars Rob McElhenney (Mac), Glenn Howerton (Dennis) and Charlie Day (Charlie) it became part of a heated discussion during a segment of their show.

The topic was kind of clumsily introduced as the stars were talking about an actress that had been in an episode of their show who had also been a reality dating show contestant. Initially Day had suggested she had been on a reality show with Axl Rose, before it was determined that it was Bret Michaels' Rock of Love show that he was thinking about.

That led McElhenney to make the claim that Rose was "one of the top five voices in the history of rock 'n' roll," which elicited a cringe from Howerton and some questioning from Day. When asked to break down his criteria, McElhenney explains, "He rocks, he’s loud, he’s consistent. But when you hear his voice, you know it’s him – it’s distinct.”

"So Axl Rose in terms of range and ability, you mean? Yeah, that's a very impressive voice. Maybe Top 10 if that's the criteria, yeah," concedes Day. Howerton adds, "Certainly when it comes to rock 'n roll, yeah."

Day is next up, shouting out James Brown, but getting some pushback on whether he was more soul/R&B or a rock singer. "That shit is rock 'n' roll man," says Day, defending his choice.

Howerton then offers Ann Wilson of Heart, despite conversation as to whether they should keep it to male singers. “I think she’s the most incredible rock vocalist of all time, personally. I think her voice is unbelievable. Have you ever heard her do [Led] Zeppelin songs? It’s way better than Robert Plant, I’m sorry. She fuckin’ slays Zeppelin,” says the actor, who then also shouts out Faith No More's Mike Patton, while noting he's wearing a Tomahawk shirt.

READ MORE: Heart's Ann Wilson Made a Bid to Audition for Led Zeppelin in Late 2000s

He continues, “In rock circles, he is widely considered to be one of, probably the top three greatest rock vocalists of all time, easily. And by many, No. 1 hands down, hands down.” While McElhenney questions the pick, Howerton adds, “That’s people in the business; like the general public, a lot of people don’t really appreciate or understand what it is he’s doing. But if you’re in the business, you can see what he’s doing and be like ‘Holy shit.'”

It's at this point that McElhenney reveals he envisioned the conversation going a different way, similar to sports talk radio discussion of the greatest basketball player of all time, with people naming stars rather than the greats, but they all agree that music is more subjective than sports where you have stats to back up your views.

Howerton and McElhenney then engage in an Ann Wilson vs. Axl Rose debate. "I listen to Axl Rose and I find it kind of grating," admits Howerton. "But I get it. I understand what you're saying and why people like it, but I don't see as big of a distinction between Guns N' Roses, and I'm going to get crucified for this but that's okay, but I don't see as big of a distinction between Guns N' Roses and like Poison as some people do."

He then reconsiders his comment stating, "To me, it's kind of ... well, that's not true. They're definitely better. [Guns N' Roses] are definitely much, much better in my opinion, but I don't know, it's still not my thing."

"Well, in fashion, look and feel, they're shopping at the same place," jokes Day tying together their similarities. "They're getting their hair done by the same dudes." Day also mentions Steven Tyler in the discussion, but Howerton returns to defending his Ann Wilson pick.

"I think she's one of the greatest rock vocalists of all-time," says Howerton. "I think she blows all of the people that you fucking named out of the fucking water. She's incredible. Look at the comments." He then suggests that none of the comments will say that Rose is better than Wilson.

Ultimately agreeing that it's all subjective, the guys eventually wrap the segment, which you can watch below around the 30:10 mark of the podcast.

So who would be your pick for the greatest rock vocalist? Would it be one of the choices that the three actors served up or do you have another pick? Get in on the conversation in the comments for this post. Heart are currently off tour, but the Wilson sisters recently resumed writing for a new record. Meanwhile, Guns N' Roses are currently touring and you can get your tickets here.

Rob McElhenney, Charlie Day and Glenn Howerton on the Always Sunny Podcast

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