1) Gaga's vocal is very well recorded. It's very natural, not overly compressed and doesn't have a lot of sibilance.
2) The vocal on the verse of the song features a very short and delayed room reverb, which changes to a longer verb with a delay with more repeats in the chorus. This is a trick that you'll hear on many pop records, and one that we recently heard on Christina Aquilera's "Genie In A Bottle."
3) The treatment on the vocal on the bridge changes yet again as it's doubled and panned left and right. It also sounds like it's lightly chorused.
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