Also what's cool about this kind of circuit is it's great for learning what everything does. A lot of guitarists look at a guitar amp and think it's magic. It's mojo. There's something each "amp guru" does special to the amp to make it sound like it sounds and they must possess some mystical ability nobody else has. And that's complete BS. Once you learn what each part of the circuit does, like oh hey if you change the 0.1uF PI couplers to 0.022uF, it does this. Or oh hey, if you change the 47K slope resistor to 33K, it does that.
Once you learn what alllll these parts of the circuit do and how they interact, you start to realize it's not magic or mojo. And what Cameron does, or what Fortin does, or what Friedman does, or Bogner or Soldano or [insert magical metal guru] does... well it's no longer hype or mojo. It's cooking. And then you can start to season your own amp to how you like it, rather than relying on a chef to cook your steak for you.