AT
Bass Station is good. But if you like it you should try Ugo Audio Rez 2. Free synth, and the best mono bass synth out there to my mind. Not sure if it is 32 bit - I'll have to check and see.
Pretty sure it's synthedit and there's no 64-bits from that platform yet is there?
Big fan of Ugo otherwise, really like his string theory.
Don't have them installed, don't know why...
I think NI's Monark gets my price right now for best bass synth by the way.