A new rosin that is out, is getting some good reviews.
"The Salzman Symphony rosin #10 is now my preferred rosin, having tried all the rosins out there. It provides the perfect amount of bite for a variety of articulation, but still allows for a singing tone in all registers of the bass. I can't recommend it more !!" - Tyler A. Shepherd , Principal double bass, Orchestra of the Welsh National Opera; instructor Royal Welsh College of Music and Drama
I would recommend either #9 or #10 depending on how much tack you want. It's a little hard to find right now, but is becoming more available.