I'll try...First the pre doesn't power the mic, it amplifies the signal from the mic,there is a difference. Mic pre's introduce a certain amount of noise/color to the incoming signal.Cheaper pre amps add more noise to the signal and add "color" (which has to do with the quality of the components inside the pre)to the signal that can be heard in the recording (turn up the gain on your pre and listen). The end result is a recording of a great vocalist, who gave a great performance that has extra crap in it that you don't want there. Not just noise, but even a change in the tone and feel of the performance. Remember that a lack of clarity isn't the only issue you can have. You can have a crystal clear recording that sounds thin and tinny.Better pre's introduce less noise to the signal and tend to "stay out of the way" of the original recording. Thats not to say that some high end pre amps don't "add" to a recording either, but they tend to add things that are considered pleasing but when in doubt your beter off with a pre that does less to the signal than more, and a cheap pre is always gonna do more than you want it to. Also 300 to 400 isn't a lot to pay for a pre amp. You may not notice that much of a difference between a $100 pre and one thats $300 but you would notice a difference between a $100 and a quality pre.
Originally Posted by undefined1211
Nothing in the world is more dangerous than sincere ignorance and conscientious stupidity... MLK