Watch the Eric Clapton online guitar lesson by Jeff McErlain from Kings of Tone
The tone we are going for here is Clapton circa 1966-68, the problem is that to truly achieve this tone you need to be extremely loud. The volume which he played at had an extremely important role in his tone and the way he played. When you play at that volume not only does the amp distort in a favorable way, there is a circuit created between you and the amp. There have been rare occasions that I have gotten to play in a large room through a cranked old school Marshall, it's something that haunts me still.