Vortex Sound Research

I was recently playing on an OB-6 and being primarily a bass player, I built bass patches. And man, the filter is so awesome, it’s just super fun! I have a Sub Phatty, which is great but the filter is different of course. With the moog I can never really use resonance, because then the foundation is immediately gone, that's not the case with the Oberheim. I wish there was a pure bass synth with the filter. Please tell me there’s a monophonic synth with an Oberheim-like filter so I don’t make my wallet and other people cry because I‘m buying an OB-6 just for bass patches…