* Different genders: Britney Spears is a female singer, while Derek Berry is a male singer. Their vocal ranges and natural tones are inherently different.
* Different genres: While Britney Spears is primarily known for her pop music, Derek Berry has been involved in various genres. Their music is produced and performed differently, reflecting the styles they have chosen.
Therefore, it is not possible to draw a comparison between their singing styles. They are both talented artists with distinct voices and musical approaches.