It has the exact same voice as the dalek that in the CE finale cliffhanger said:

"They survived through me"

I don't think it's the exact same voice, but it is much deeper like the Emperor Dalek.

I noticed that it sounded like the Dalek Emperor as well, but it's only because it has a deep voice as the Emperor did. I don't think there's anything to read into it.

Same as the Supreme Dalek from Stolen Earth as well.