Based on the KT66 platform of the old Bluesbreaker, with a few twists.We are now shipping the amp with the new TAD 6L6WGC tubes or with the Chinese KT66's. Through a bunch of legwork, I have finally found a good supplier of KT66's, and have been using them as well as the 6L6's.. The amp still has that killer vintage vibe. 4 inputs, a higher gain brighter side, and a lower gain darker side. Original design was a shared cathode in the first preamp tube which gives the amp its overall darkness, but we incorporate a Vintage/Modern switchable first stage from shared cathode to split cathode, which will make the amp a little brighter and more aggressive, give it that classic lead snarl. Like all of our amps, we use only the best for components, each amp is built to last a lifetime. Also, we can custom tailor each amp to the buyer, with subtle voicing and gain structure changes.