Preamp Recommendation for First Watt F4

I was referring to the more recent Pass Korg B1, much better than the original Pass B1.

I would build the basic kit without mods before investing in an expensive tube line stage. Careful with used units since the Korg Nutube 6P1 is very microphonic which will cause problems if not mounted properly. This inexpensive kit will improve that considerably:

Anti-vibration Mount for Korg Nutube 6P1

I'm guessing mine with mods and external linear supply will hold up well to both my main tube lines stages, both above $10k, especially since I will be able to dial up any amount of second harmonic distortion by simply adjusting the bias pots.

I am using an Usher P307A with my rawsonte F4. Possibly the best amp/pre combo I ever had ( with Lascalas ). Enjoy ! MrD.

My guidelines are single ended, 20+db gain, and preferably tubes. Not ideologically opposed to solid-state, but think tubes are better fit in general. My short list:

This is a proven alternative to drive the F4 cleanly to rated output. ra7 said he will may have an updated version available later this year.