OK - and I'm more-than slightly confused as to why you'd discourage him from doing this (even with the emphatic, 'incredulous triple-question marks'!).
Arnak is a six-string, extended-range bassist - maybe a soloist. Is the question 'why would you want to perform with percussion'? Many bassists very-much like performing with percussion. The specs on his Markbass cab rates it for 40Hz to 18KHz - I'd say if theres a 'speaker problem', it's solidly reproducing the LOW-end of his instrument's range!
Joe, I get increasingly annoyed when people feel the need to slate peoples responses to questions for no reason, I feel maybe your a little mixed.
1. I'm the one who plays the 6 string fretless extended bass with a Mark bass (yes it is a very nice amp, thankyou). According to Arnak's profile he plays 4 string with no mention of amps (thus not being able to tell if it would be an appropriate amp for a drum machine)
2. I think to assume a bass amp is not the appropriate amplifier for performance drums is fair...The fact is that no matter how good a bass amp is, its designed for bass, unless you bypass the preamp/EQ's/compression and anything else your amp is doing to the sound it will sound strange, I would suggest plugging the output of an ipod into an amp setup for bass as proof of this then compare to a good quality hifi. Of course you CAN plug a drum machine into a bass amp and the better the amp teh better it will sound (the reasonable flat nature of Markbass actually makes it a good candidate for this!) But there are more appropriate amps out there for more serious performers.
3. Read the rest of the thread, Arnak is not using it for performance, and the conclusion was to use a mixer. Also I'm not sure where you got the idea that I'm against people using drum machines...its great, I love it, bring on the bass soloist we need more of them, more people like you if thats what you do!!
All the best with your solo work, seriously, I'm here to make friends, encourage bassists and offer advise where I can not to get slated for what I thought was a reasonable suggestion... Come on mate...us bassist need to stick together!