Verified answer

You have asked two different questions. Dio had the better voice IMO, but Rob has greater range.

Agree with MCMG on Painkiller. That song shows Rob's range quite well.

Halford has a wider vocal range. Halford has done higher highs and lower lows than Dio did (forgive me if I'm wrong, I haven't heard each and every Dio song yet).

'Better voice' depends on a person's preference. Dio had a great voice but I prefer Halford's. I think this has to do with the fact that I think he has taken part in overall better music.

Ronnie James Dio had by far the better voice, but Rob Halford always came across as a nicer person in interviews.

Rob Halford

Better Voice: Dio

Wider Vocal Range: Dio

(http://www.youtube.com/watch?v=hvvjiE4AdUI Skip forward to about 2:45 and listen til 3:30)

Rob Halford.

Dio was the better singer, but Halford is amazing too. Both are legendary metal vocalist

Dio <3 Not taking anything away from Rob Halford, but Dio Pwns!

I love both ,but I'll go with Halford

RIP Dio

Dio