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 Rivera amps too! This kit uses a JJ 5751 for V1 which is in-between an ECC81 and an ECC83S in gain. We follow that up with four ECC83S's with one being a current balanced ECC83S for the phase inverter in V5. 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 by clicking on the "Customize" button.