Beyonce.

This....

Beyonce is clearly more urban than Rihanna. That is her niche.. Her voice REALLY shines in that genre (especially RnB). Listen to her more "pop" songs..even they have extremely strong RnB (urban) influences. From her syncopated phrasing, her prominent vibrato, the little naunces that's ever-present in that type of music: vocal sliding, "riding the beat", indulgent use of harmonies.

She's using grit, rasp, which originates from gospel music--the remarkably interesting "scawl". She does all of this and it extremely natural. Beyonce has an INNATE understanding and affinity for this genre of music..

Although, a 'popstar', she is COMPLETELY urban..even moreso than Rihanna.

Let's add this perfect example of Beyonce's authentic urban signature sound.

Somewhere over the Rainbow is a NON-URBAN classic broadway ballad, yet Beyonce flips a switch at 1:35 and goes off on this jazzy/rnB tangent and completely nails it! listen to 1:35 - 3:00..

In many instances she starts improvising on the pentatonic scale, which is especially heard in a lot of blues-based music..Her jazz based chord progressions can be found throughout the second half of the song..

Although, she's perfectly able to give an authentic interpretation of any given genre, her "roots" always find its way at the forefront of the song. It's her signature sound; anything in the realms of rnb/soul/gospel/jazz. etc is where she flourishes.

Obviously Beyoncé. I mean, Urban is her main radio format while Rihanna's main radio format is Pop.