Soul Recommendations

I really enjoyed the Jazz Recommendations thread, and it is refreshing to get away from the religious debates on equipment. An area of music I want to explore more is soul, and am looking for some help. There is some cross-over between what I like and R&B, but I don't like much R&B released in the last 15 years or so, and there is also much cross-over into Blues. So what I do like in this area is - James Brown, Junior Wells and Al Green. I also like the old Stax stuff (I have the boxed set). But that amounts to my entire soul-tinged music collection - a dozen or so CDs. I don't care for Parliament, Barry White and so-called "sweet soul music" - eg. "Sexual Healing". I know my Jazz and Blues very well, and have very extensive collections there, but in crossing over the line into Soul I have found some great stuff by the artists I have mentioned, but feel I am only scratching the surface and want some pointers (pardon the pun) as to what to go for next. Maybe you will tell me that JB, Junior and Al are it, but hopefully there is more to explore.