Studio monitors come in two varieties, powered and unpowered.
Unpowered monitors require a power amp to feed them. You would hook them up to your present equipment as follows:
-------------------------------------------------------------------------------
Computer sound card line out -> splitter cable -> power amp line in -> power amp output goes to the monitors.
yup - you gotz to buy a power amp.
You plug one end of the splitter cable into your sound card, it splits the left and right channel into separate connectors. Most splitter cables have a tip/ring/sleeve connector on one end and two RCA jacks on the other end.
You could also listen to your sythesizer through the monitors, but that would involve connecting the sythesizer line out to the power amp input. You could also buy a mixer, that would make getting multiple sound sources into your computer and out to the monitors a lot easier.
---------------------------------------------------------------------------------
Powered monitors have an amplifier built in, so...
computer sound card -> y cable -> monitor inputs.
-----------------------------------------------------------------------------
You may run into issues connecting various pieces because they use different connector types, i.e., RCA vs 1/4 inch vs Balanced, etc... just explain what your are trying to do to your friendly Radio Shack employee, or ask one of us.
Good luck.
