Hi all, long time fan of the forum, but I finally registered to post this question:

I've been using a Behringer FCA202 firewire interface for a few years. As far as I understand, unlike many sound cards, it does not have any onboard pre-amp and is only meant to take "line" inputs, but not "mic" or "instrument" level inputs. So normally I plug my electric guitar into an Amplug headphone amp before plugging it into the FAC202. But, here's the funny thing: I forgot about that today and plugged my electric guitar directly into the input, and fired up my DAW, and it turns out that not only do I get a signal that is loud enough to be usable, but it is actually a very clean and natural sound that I can then do what I want with using amp sims, etc.

So my question is, is there anything "wrong" with this connection? Why does Behringer insist that you need a preamp?
i know it doesn't really answer your question, but i have found a similar situation when plugging my guitar into the line in instead of instrument input on some cheaper amps. i find the sound is actually better. i dont think there's anything wrong with this connection. i think they just suggest you do that so you can have some control over the tone (preamps generally will give you some sound shaping).
I'm guessing that it will work with some signals but not others. It seems to work fine with my electric guitar (humbucker pickups) and I also got a strong signal from a piezo pickup for an acoustic guitar, but when I plugged a dynamic microphone straight into the line input the signal was kind of weak.
They say to use a pre since that interface doesn't have a built in pre. Most devices (like your dynamic) won't have a loud enough signal without it
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