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. Well, this works really well with the Dr. Z amps too! This kit uses a JJ 5751 for V1, a standard ECC83S for V2 and a current balanced ECC83S for the phase inverter in V3. The kit includes a JJ GZ34 rectifier tube and a matched pair of JJ EL84's for power. Mike recommends a JJ gt #6 for power but since we have 30 different grades of the JJ EL84's and we know where the bias point is on these amps, just let us know in the comments section if you're looking for an early breakup, a moderate breakup or a later breakup for more headroom in which case we will choose the coolest grades we have available for the power tubes.