Controllable Bass Mpc for Soft Dynamics

Don't laugh too hard, but I am in need of a bass sax mouthpiece for a Buescher bass that is relatively capable of playing at soft dynamic levels and preferably with a nice sound. I realize this is an odd request, but I really need something that will get out of the way of other instruments in an intimate setting where soft dynamics are necessary. The less the piece sounds like a chainsaw, the better, but QUIET is the real issue here. I've not yet come to a conclusion on whether a close piece with soft or medium reeds is going to be better than an open piece with soft reeds. Bass mouthpieces just aren't as accessible to try out as others, so I'm looking at using baritone mpcs that are suitable for use on bass . Next to changing mouthpieces, with consideration that this *is* a bass afterall, I believe I'm doing what is humanly possible playing-wise to control the dynamics, but I'm not happy with the results so far. Bass is in good adjustment. I'm open to suggestions, especially on reeds for use with whatever mouthpiece you might recommend. I really could use some advice from experienced bass players, even if it means custom mouthpiece work from someone who knows what they are doing.