Looking for more headroom and a softer attack? This is our Tweed Retube Kit for the VOX AC4C1. It contains a single JJ EL84 for power along with a 12AY7 in V1 and an ECC83S's in V2 for the preamp. This option reduces gain and offers a rounder and slightly more compressed overall sound. Just let us know in the comments section if you're looking for an early breakup, a moderate breakup or a later breakup for more headroom in which case we will choose the coolest grades we have available for the power tubes.