Hello fellow UGers!
I recently started using Guitar Rig 5 (Native Instruments) and I am thoroughly impressed with the functionality and sound of the software! It's great to have such an array of effects and sounds at my disposal in one compact place (my computer). This is especially useful considering I live in a small apartment. I currently use a USB audio interface (Behringer UCA202) on my laptop (and a PCI audio soundcard [M-Audio Delta 1010LT] on my desktop computer) to connect my guitar to the computer for use with Guitar Rig 5. I then output the sound via two RCA audio outputs (converted to a 1/8" or 1/4" plug/cable) to either headphones or an old crappy 25W guitar amp that I have. The sound quality is not that great using either, however, and this is why I am seeking your advice! Essentially, I would like to get a pair of reasonably nice general-purpose speakers (~$100-150 ballpark...I'm a poor grad student!) for use with both my electric guitar and electric bass to output the Guitar Rig 5 sound, effectively using the software as an amp head and the speakers as a cabinet (collectively a custom amplifier). Admittedly I am rather inept with electronics besides very basic stuff, and I suspect that based on power requirements, impedance matching, etc. that it won't work correctly to just wire the RCA output from the audio interface (USB or PCI card) directly to the speakers (which use speaker wire, and not just crappy 1/8 or 1/4 cables). Assuming this is the case, what is the intermediate component that I require to connect the audio output from my audio interface to the speakers? I suspect I may need a pre-amp, but I would like to go as generic as possible, as there are already pre-amps simulated in the software which I would like to use, as I have read elsewhere that using pre-amps designed for a specific purpose (e.g., guitar amplification) together with the software's pre-amps gives crappy results. Thanks in advance for your help!

Also, for the record here is a set of speakers I was looking at for my prospective venture:

...suggestions are also welcome, however

P.S. I think--were this feasible--it is a cool idea to use the Guitar Rig 5 software as a sort of "brain" for my sound, and the next step for me would be to design/create a customized stomp box using a microcontroller with the appropriate programming (yikes!! despite being an engineer, my background is more in biology!) to send MIDI information to Guitar Rig 5 for switching on/off effects, incorporating expression/effects pedals, recording loops, etc. ...but one step at a time, of course!
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You could always just save up and buy a POD HD. Everything you're looking at doing except the speakers is already there.
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