What he wants is a program that converts the analog drum sounds into MIDI info based on the frequency of the sound. I’m not aware of any linux program that does this (maybe ecasound or pd or some of the more exotic software).
If he’s really lucky the KT plugin will work in Ardour otherwise signing up to Linux Audio Users (http://lists.linuxaudio.org/mailman/listinfo/linux-audio-user/) and asking around there might be a better chance of getting good info.