it's not retarted
but
to do it well requires much skill and attention to small details

if you must then I'd start with a kit
or
exceptional plans with the correct parts and not substitute parts

Try some of the kits at http://www.madisound.com/. Alternatively, you may want to go with single driver/speaker monitors - some fostex driver speakers could be nice, see http://melhuish.org/audio/links.html. Most of the stuff in the links is audiophile, but if you chose high-end components there may not be much difference. An article on hifi vs. studio monitors can be read here: http://www.soundonsound.com/sos/Jun02/articles/monitors.asp. I personally love Tannoy speakers, both for hifi and monitoring mainly because they are easy to listen to loud for an extended time.
If you are looking for nearfield monitors, as a bass player you may find it difficult to be happy with any monitor that is may not have a full bass extension (E on bass is about 40 Hz, right?) or doesn't use a subwoofer. Hope this helps + cheers,
Buzzgrowl

Why go through all that trouble? First you have to make sure your cabinet design is solid, and the right size (yes size affects the sonics).

Most important... You can buy a decent pair of studio monitors fairly cheap now-a-days, and it will have that professional finished look, oh and actually work as intended.