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 and two ECC83S's with one being current balanced for the phase inverter in V3. The default power tubes are a matched pair of the JJ 6L6GC's but you can configure this kit to use the JJ 5881's or even the JJ 6V6S's to drop the power output a couple decibels by clicking on the "Customize" button!