Found this nice little post while Googling "unity gain" - Technically Unity Gain is an operating point at which the amplitude of the signal going in is the same as the amplitude of the signal coming out of a gain stage.
A Gain Stage is simply any device that is designed to enlarge or shrink the amplitude of a signal, and do it accurately. (More or less.) A single gain stage is also known as an amplifier.
What we think of as an amplifier is actually a big collection of several types of gain stages, each designed to alter the signal in a different way. Generally when we say "amplifier," it's sort of a slang-type usage for talking about a whole box full of gain stages, as in a guitar amp.
So what's Unity Gain? Signal going in is as "loud" as signal going out, roughly speaking. But which part of the signal? The attack, the body, the decay, the overtones? What decides where Unity is--your ear or the circuit that gets the signal? Your ear may tell you it "seems" to be the same, but electrically the circuit may see an entirely different response, and do very different things to your signal than it would with a truly matched amplitude.
Fortunately, your ears are a pretty doggone good guide with guitar rigs. You have lots of clues: Are the two sounds equally loud? Equally EQ'd? Equally clean? Equal distortion? Does the sound sit in the mix the same? Do you hear the pick the same? Does it sustain the same? Do the dynamics match?
As you might gather, depending on which of those criteria you use, your intuitive sense of where Unity Gain is may very well be different, and for valid reasons. Ultimately, when we're talking guitar rigs as opposed to pro audio, it's an artistic decision and it's all about whether you think it sounds "good."
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So, it looks like I need to continue my research. I'd like to keep this pedal and I might also like to add some distortion on top so I guess an early step might be to determine which effects I would like and how they will affect my overall volume concerns. I did spend some time tonight playing with the Sensitivity knob and my right hand in order to get a feel for the pedal and how my technique works with the filter... its difficult to gauge from headphone use but that might be a simple beginning point for dealing with these rogue frequencies.
