Allan Holdsworth was a genius. Obviously. I always thought that the Drive/Amp were the important part of his tone, and have bought the J Rockett Holdsworth drive a number of times to see if I was missing something. After playing with both the Yamaha MagicStomp and the Yamaha UD Stomp - which Allan used for a huge part of his career, I’ve found what I think is the MOST important part of his lead tone.