Her alto sounded better when all 5 of them where there and she could blend with dorinda but she started singing tenor. I think she sounds better singing tenor with Twinkie and letting dorinda handle the alto.
I actually prefer her singing Alto just because Dorinda sounds so great singing tenor. Of course Dorinda can sing much higher than Jacky but her alto notes are more raspy and labored.
Dorinda voice is actually huskier than Jacky and Jacky has more of a rich sound with hers and is fuller than dorindas voice. They both can sing about the same notes but it’s easier to push out for Dorinda because she’s use to using her voice more and experimenting and Jacky isn’t but when she does she actually sings very high.