Performance

Storytelling, musical recitals, and plays involve one or more people performing for an audience. Performing for an audience usually involves a roll of Charisma + Performance difficulty 6. The difficulty can be modified up or down depending on the material used and the mood of the audience.
At the storyteller’s discretion, performers with stringed or percussion instruments may roll Dexterity + Performance in lieu of Charisma. Performances with a strong sensual aspect may involve Appearance in lieu of Charisma.
One success means the performance goes over well but is not particularly inspiring. Three successes means the performance is likely talked about for weeks. Five successes means the performance is likely talked about for years to come. A failure means there were one or more minor problems. A botch indicates that a performance is memorable for all the wrong reasons.

Are gnomes better singers?
Gnomes get a -1 difficulty break on nearly all Charisma rolls and this includes Performance.  Does that mean gnomes are naturally better singers than humans, dwarves, or elves.
No, not really, if you just listen, most Scarterrans will say that humans or elves have nicer voices, but what gnomes are good at doing is reading social cues and they are generally better at working the crowd then other humanoids.