filters

[james fowler <twostroke@gmail.com>]

i need a good filter.  primarily for synth filtering.  for space reasons, i'm leaning toward software...are there any out there that do a good job?  i get the impression that something like a filter belongs exclusively in the analog/hardware domain but going that route will necessitate upgrading my rme multiface as it's already completely full...i'd need another one or something bigger.  

thanks.

- jim