I want to mention a couple things here about the head building aspect in Head Case..
Head case was not designed to be a one to one electronic component matching system. First off thats not possible for a real time system no matter what type of snake oil you're getting sold, and second that would make head case a modeler, something we just don't support as a company.
This allowed us to remove whatever modeling limitations there is and just concentrate on making this thing useable by anyone. So, the question became if we are not modeling, then what is the driver, how will the user decide what to do, what changes to make, etc. The driver in head case is your strongest asset as a musician, the driver is your ear. So you open a head that gives you a tone close to what you're looking for. Lets face it, you will never get a head to perfectly match your tastes unless you can edit it yourself. So all heads you open in head case should be thought of as templates that can be edited very easily.
"I like the MAHAKALI, but it has a little too much bass and I want it to have more of a flabby distortion." You can do that, you simply open it in the builder and start playing around with the controls, as you do that, if you have played on a lot of different amps, you'll start to hear tones that sound familiar. Its this familiarity that will allow you to learn what does what faster. You'll get to remember when I have "that" control there it reminds me of my roland cube, when its here it reminds me of my old Traynor TS15..
You design a head like you would mix a track, in fact arguably, mixing a tack is more complicated. All you have to remember is one rule, bass into distorted curves (tubes) = big muff type tone. If you want more of a flabby tone then set the precuts and the channel cuts to more bass.
If you want more info, here is our youtube channel. This has some videos that explain things like signal flow, etc. As time progresses I'll be making more videos, so sorry its a little sparsely decorated right now.. haha
http://www.youtube.com/user/acmebargig