What is the optimum set and rep range for mass gain?

Discuss.

For me it is usually high weight low reps like 7,5,3,3,3

for compound movements like bench and squat I keep them between 5-8 and for isolation movements closer to 8-10.

I like to do two sets of med. weight, like 10 reps or so, then do three heavy for as many as i can, with a weight i can't do anymore more than 5 though