snd-cs46xx doesn't do wavetable synthesis
I got a Turtle Beach Santa Cruz sound card which is driven by the cs46xx ALSA driver, but much to my dismay there doesn't seem to be a way to get its wavetable MIDI synthesis to work in linux. So I guess it's back to the softsynths for me, e.g. fluidsynth. They're not so bad, but I think the card would have done a better job of it.
Still, it's a good card.