Board Thread:General Discussion/@comment-2055856-20160626200733/@comment-33300401-20160811170439

Actually Kroshy, Jaleel didn't provide any of the character's singing voices

Sonic's singing voice was done by Samuel Vincent (more popularily known as the voice of Double D in Ed, Edd 'n Eddy)

Manic's was Tyley Ross who is an actual singer and help co founded some music recording company

Sonia's voice was Stevie Vallance who I have never heard of - it's ironic that her speaking voice was done by a male while an actual woman voiced her when it came to singing