Want all the gain you can get? This is the High Gain Option Retube Kit for the VOX AC30C2. It contains a matched quad of JJ EL84's for power along with a three handpicked High Gain ECC83S's with one being current balanced for the phase inverter in V3. Just let us know in the comments section if your looking for max headroom, moderate or an early breakup so we can select a proper grade for the power tubes.