I don't know what strings Ramblin' Jack uses but I imagine whatever type they are, they won't be a light gauge. As has been mentioned earlier, strings are very much a personal choice and of course, much depends on the type of guitar that you've got. I use Elixir Nanoweb phosphor bronze medium gauge on my 1957 Gibson J200 but use Newtone Heritage 'low Tension'light gauge on my Lowden S12. The Newtone strings are a joy to play on and the little Lowden positively sings with them...