Just because it's unbalanced doesn't necessarly mean it's a going to be a super high impendance signal. Most LINE-IN's on mixing consoles accept BOTH balanced and unbalanced signals. But take note their is only a certain
level of impendance a
console can take when accepting an unbalanced signal. Most
passive insturments are too hot, or are too weak and noisy by the time the signal reaches
FOH. Heck, your not getting a good signal past 40 feet or so. In some instances, you can lose as much as 1-2db for every 10' of unbalanced cable. It'll still work, but the longer cable lengths make the signal prone to interferance. Believe it or not, but a surprising amount of audio processing gear can be ran unbalanced without any troubles. A majority of people run their CD players unbalanced (
rca and many 1/4" outputs are unbalanced. Anytime you hook up a serial
effect via an insert with a
TRS y-cable, you're running unbalanced. About 95% of the time when I use compressors/
dynamic processing, I run it unbalanced, because I connect it up as a serial
effect. No
direct box needed here. Usually you don't need a
direct box when using unbalanced processing gear because they usually have a relatively low impendance (low enough so it's not going to fry your
console). I see analog guitar effects used on vocals at front of
house all the time. Usually, it's an analog delay, tape echo, or some sort of
reverb/
reverb tank. In sound it seems like we're always taught to destroy those unbalanced (I try to run every balanced as much as possible) signals and
whip out that
direct box asap. We were probably all told this because it's not a smart idea to run an unbalanced signal from the
stage to
FOH, which can 150'+ run easy. But there are some instances when you work with unbalanced signals peacefully. I know this can be confusing, but there isn't always a rule of thumb you can follow by. The best thing to stick to is to find out whether it's balanced or unblanced, then figure out wht the device's impendance is.