I always confuse the Dynamics, the Delfonics, and The Stylistics.
The Dynamics are from Detroit, signed to Stax, and continue to perform today (in a newer lineup, natch)
The Stylistics were/are Philly Philly PHILLY.
Despite that, this ballad still managed to fight past Journey, Boston, and Foreigner for play at my middle school dances in Michigan circa the early-80s:
Here’s my favorite obscure Stylistics track, from 1973:
Here’s another ballad that managed to sneak into the gymnasium slow dance. ..and it’s got the whole astrology theme like the first track above. The original of this tune clocks at almost 12 minutes:
The Dramatics are another one. Also from Philly, also still kicking.
And since I’m mentioning Philly soul groups, I must include The Intruders: