Not all bass straps are created equal. I had a buddy always complaining about dive on his Jazz bass. As he was showing me the bass one day I noticed his strap was basically a woven nylon car seat belt style strap. There isn’t a strap out there that could be much more slippery that that. New leather strap, problem solved.
I’ve also tried grippy suede straps on some of my basses and hate the feel and the fact that it grips my shirt so well that it untucks my shirt tail and bunches up the shirt fabric on my shoulder - hate that, I no longer use them because of it.
I’ve also used the thin belt with a wide fleece lined shoulder pad style strap and found the shoulder pad stayed in place but the strap slid thru the pad and created neck dive.
My favorite is a Levy’s brand 3” wide padded leather strap with padded edges to keep the strap from digging into my neck…
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