Stevie liked playing loud 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 V3, and a matched pair of the low output JJ EL844's for the power section.
These amps are fixed biased, there is no bias adjustment to be made. The amount of clean headroom you’ll get from the power section is somewhat dictated by the grade of power tube used. The JJ EL844’s are a drop in replacement for EL84’s. The EL844’s will reduce the power output of the amp by a decibel or two.