1. Sade: British singer-songwriter with a distinctive, smooth, and soulful voice.
2. Norah Jones: American singer-songwriter known for her warm and smoky contralto voice.
3. Alicia Keys: American singer-songwriter, pianist, and actress with a powerful and soulful voice.
4. Amy Winehouse: Late British singer-songwriter known for her deep and expressive voice.
5. Duffy: Welsh singer-songwriter with a sultry and raspy voice.
6. Macy Gray: American singer-songwriter with a unique and raspy voice.
7. Adele: British singer-songwriter with a soulful and powerful voice.
8. Corinne Bailey Rae: British singer-songwriter known for her deep and bluesy voice.
9. Erykah Badu: American singer-songwriter, rapper, and actress with an eclectic and experimental style, often featuring her soulful vocals.
10. India.Arie: American singer-songwriter known for her distinct neo-soul style and soulful voice.