We want to capture the mic signal/voltage without any intervention - and so accurately that we can use that signal to run into ANY preamp to achieve the sound we are looking for...make sense...?
No, to me it really does not make sense. Perhaps in some completely theoretical world, but not in any real-world sense. I can understand that you want to capture exactly what the mic is producing -- which is a very low level AC electrical current -- but there is no way to do this perfectly and exactly. Any means by which to do this, whether capturing it on ferro-magnetic tape oxides or by digitizing it and storing it as a set of digital information, will add noise and anamolies to the original AC electrical signal coming from the mics. Engineers can do their best to minimize this, but there will always be some level of noise in the system that they design. The problem then is that the electrical signal coming off the mics is very small and on the order of the level of noise inherent in the system. This is the noise floor that JKLabs alludes to. It simply turns out that the best way to configure a system to most accurately capture that electrical signal coming from the mics is to add gain to the signal (as in the function of the mic preamp) so that the inherent noise of the system has less of an effect on the now higher level signal that is captured and digitized. The process of adding gain adds some noise, but overall, the amount of noise and anomolies that the original mic signal is subject to is less than if no gain were added.
The bottom line is the systems we are using, including a mic preamp stage, are the best methods available to try to meet the theoretical pinnacle you're seeking -- an accurate capture of the electrical signal coming off the mics. My guess is that the components simply are not available/able to be produced that can have a low enough noise floor that a low-level mic-produced electrical signal can be captured accurately without first applying gain to that signal (ie, using a mic preamp). And even if such components could be made, they would need to be perfectly tuned to the sensitivity of your mics and the decibel level of the event you are trying to capture. So even if they could be made, you'd need a different system to record Mule and a different system to record Yonder Mountain, and a different system to record un-amplified chamber music, and a different system.... Just not practical at all, and as I said, nothing that is able to be produced at this point anyway.
Topic: Why the heck do we use preamps anyway? (Read 11515 times)