The Balanced ECC83S is located in V3 closest to the power tubes and the High Gain ECC83S is located in V2.All Combo amp Retube Kits are shipped with the Eurotubes Double Mica 6L6GC’s at no extra charge. JJ Electronic started building us a proprietary version of their 6L6GC (the 6L6GC-DM) in 2005 with extra layers of mica. This reinforces the plate structure and all but eliminates tube rattle symptoms. If choose to go with 6V6’s and you play by yourself in a quiet environment or record with your amp you may want to consider using the EuroDamper tube damper rings. These are available in the "Related Products” tab as a set of three and will greatly decrease tube rattle.