I don't remember who it was, maybe @winders, who wanted a preamp... TBH, this is something I kind of want for myself. A lot of people have ideas, and most of them don't get Craig's interest. And I know Craig likes to do something different, something that will interest him. So last week I planted a seed: Would you make a custom 45 tube preamp if I gave you $2000? We discussed some ideas pertaining to implementation, like leveraging the high frequency heaters for the 45 tubes. A few days later, I get an e-mail from Craig that he likes the idea. Any interest? I know it's pretty nuts using a 45 tube, but is some ways seems kind of neat because we can use a high frequency filament heater. The 45 doesn't have much gain. And the plate resistance isn't super high.