Таки что такого?
"First of all, we weren't using a flat-radius fretboard," Mayer says. "We were using the normal one, not the very high radius but definitely curvy. The actual strings we used were not what people would expect. The string gauges would run .010, .013, .015, .026, .032 and .038.
The big difference there is that you're using the .015 for the third, because if you use the .017 for the third, the actual sound of the guitar is very G-heavy. The electrical output of the strings is dependent on the square of the diameter; if you square all the diameters and look at them, you can get much more of an idea about the balance of the guitar.
"You should always remember that, because many, many times people use a set of strings that are completely imbalanced and they just don't sound that good. Most people would say a .010 to .013 is the correct jump. And the .015 is much better for the G than a .017. An .015 squares out at .225 and .017 is 289. So you're going to get 28 percent more output just with a two-pound different in string size."