Yeah it is likely the tone bender or Sansamp you’re hearing on Tempest. In all the interviews surrounding the FI release there’s no mention of anything but the tone bender or GT2 for distortions. Also it’s misleading but I believe that Overdriver pedal is actually in the pedal chain with all the rest of his fx (whammy, modulation, fuzz, wahs, etc.) rather than after the Boss Bass EQ. That spot on his board is sort of a place to add on things. As seen in this photo from 2019-2020, where an extra Boss DD3 is in its place.
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