I don't have a blofeld or tanzbar or an Audiobox. But if it was the case, I would connect the BSP midi out to the Tanzbar midi in, the Tanzbar midi thru to a midi in (blofeld or audio interface). I never use the clock out or in of my BSP to sequence midi, my BSP receive midi clock via midi in.
But I don't know if you want Ableton, the BSP or the Tanzbar to be your master clock…