Batman's voice in Burton's films

[Edd Grayson]

Blame Nolan for Bale's voice, not Keaton. Keaton and Conroy knew how properly disguise their voice.

[eledoremassis02]

Its really kind of annoying how Nolan gets a lot of credit for a lot of things that the Burton movies did before. But I'm glad people are beginning to realize (or remember) that there were dark Batman Films pre-Nolan.

[The Laughing Fish]

I think people knew deep down that the voice started with Keaton, but they never wanted to give him recognition until this recent attention with Birdman.

I found another article where Keaton explained his approach to Batman once again during a ceremony paying tribute to him as an actor.

In 1989, Keaton got to work with Burton again for "Batman" and he developed the rough voice that the superhero became so iconic for. He was, in fact, the very first Batman that gave Bruce Wayne a different voice in the suit.

"I'd move from Bruce Wayne to Batman, [and thought] he had to transcend. I worked out this whole bullsh*t actor-y thing. I thought, 'I gotta have something that makes me believe I don't walk out on the street in this big rubbery suit and people think — hey Bruce Wayne is out again.' So I did the voice. And we just used it. Every time I was Batman I altered my voice."

That bullsh*t actor-y thing became the basis for Keaton's Birdman voice. "[For "Birdman"], the voice got crazier, with more incarnations of it. And then it grew from that."

Source: http://dailynexus.com/2015-02-05/emotions-spring-up-during-michael-keatons-tribute/

[Furstmobile]

Keaton has been telling these stories over and over recently due to Birdman.

Here's another:http://spinoff.comicbookresources.com/2015/02/13/flying-high-with-birdman-keaton-looks-back-on-batman-beetlejuice-and-more/

I'm doing this scene in Gotham — it's lit and kind of big and relatively bright, and I'm doing a scene, with a dignitary from Gotham and I'm saying, "Tim, he's going to stand there and go, 'Hey everybody, It's Bruce Wayne. We figured out who Batman is!' You know what I mean? He sees me. I just don't know how to play –" People are thinking, "Well, it doesn't matter — It's 'Batman.'" No — It matters a lot! I don't know how to play this. I said, we've got to figure out how — so we started to figure out how to shoot me where I'm kind of off in the shadows or kind of on angles. And really worked really great. But the voice, I thought, "This is just going to make me laugh. This is silly."

I'd already worked out a whole thing that kind of showed up, kind of didn't. Like hanging from the thing was my idea, hanging like a bat, and I used to do this thing where I'd move from Bruce Wayne into Batman, the transformation. I'd worked out this whole bullsh*t actor thing because I had to have some reason. So I said, "Hey, man, he's going to hear the voice and go, 'Hey, we just figured it out! '"

So I created the voice. I got to have something that makes me believe that I don't walk down the street in this big, black, rubber suit, and people go, "Bruce Wayne's out again?" So I did the voice, and then we just used it. People think it was electronic — It wasn't. It was me. Just every time I was in as Batman, I just kind of altered it, because I had something in my head that I could rationalize to play it, frankly. So when I told that story to Alejandro on Birdman, he thought it was the funniest thing I did and starts laughing like crazy. He said, "You have to do that!" And then the voice got crazier, the incarnations of it. We did everything — the post [production] on the voice alone went on forever.

Doing a scene with a dignitary from Gotham, in the Batsuit? Bright light? WHAT THE HELL'S HE TALKING ABOUT

[The_Batman_of_1989]

I had a thought that occurred to me right now. If Batman '89 was the first live-action adaptation for the main character to speak in two distinctive voices as Bruce Wayne and his alter ego, then how Burton and Keaton never seem to get any credit for it? Granted, Kevin Conroy went one better in BTAS by speaking by acting as charming as Bruce Wayne and brooding as Batman. But still...

Short answer? People just seem to flat-out resent both B'89 & Returns, & therefore talk down (or just completely deny) their redeeming qualities & contributions to onscreen (& offscreen, for that matter) comic lore.

[Short answer cont.] 
I've noticed that, generally, when the films are derided (as they so often are), whether it's a vitriolic youtube comment or a protracted, nitpicky essay on some guy's no-traffic blog, people have little-to-no legitimate criticism for the films (at least for B'89).

They're penned mostly by guys who seem to have this rather deep-rooted dislike for either Burton or Nicholson (each has his own group of dedicated detractors, I've found), or guys who simply resent Keaton's Wayne for being skinny & bushy-haired. They seem to try to mask it by adopting this sort of passive-aggressive demeanor in their 'critiques', & then mostly repeat stuff they read on someone else's blog or youtube comment (seriously, it's like they just cut & paste - "Jack just played Jack Nicholson in makeup", "Batman doesn't kill", "There's no story/the story is too simple", "Joker shouldn't be responsible for the death of Batman's parents", etc.)

In other words, stuff that's either simply untrue, or which they personally dislike, but which made for a stronger story arc, character dynamic or film overall.

Sorry for going off the trail a little bit there.