an input is an input, pretty much- on most modules anyway. Just set the trigger parameters the same for both inputs and you should be OK.
Many bass-drum-triggering drummers seem to use the Alesis modules, no sense dropping a lot of cash on a high-end module if you only need to trigger the bass. the DM5 is a common choice for this.
An old Roland or Yamaha module would do the trick too, if budget is a factor.
Generally, you're going to be able to assign any sound to any input.
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analog missionary
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