It's no secret that Stevie played his amps cranked and preferred a little cleaner sound from the front end, allowing you to hear more power tube breakup. This kit uses a JJ 5751 for V1 which is in-between an ECC81 and an ECC83S in gain, a standard ECC83S for V2, a balanced ECC83S for the phase inverter in V3, and a warmer grade of JJ EL84's for the power section. A real nice combination!