If you’re going to use the nobles, set the spectrum knob straight up the middle for no EQ. To the left it has reductive EQ at 2k and 300hz, to the right, boosts both those frequencies. Up the middle it’s neutral! There are lots of low gain drives and boosts that you could use in this way for harmonics.
The Neve-like pedals (broadcast and colour box) will probably get you more of that transformer harmonics vibe in the same way you’re accustomed to. Some thoughts/pedals that come to mind below with that more specific transformer vibe!
Hudson Broadcast, JHS Colour Box, Origin Effects RevivalDrive, Xotic pedals, Fairfield Barbershop, Effectrode LA-1A, Strymon Dec.
Would the Origin Effects DCX Bass fit anywhere here?