Preamp for First Watt F7

I ran a Rogue RH-5 with an First Watt F6 and thought it was an excellent match. I just received it back from Rogue with a clean bill of health if you're interested. I also have a bunch of spare tubes if you are so inclined.

I'm looking for a warmer sound signature. I am no longer a critical listener, just want something that sounds good without bright edges. All of the components (Pontus, Tannoy, Firstwatt) lean towards that. The more I am reading up on things the more I'm leaning toward a tubed preamp. I've reached out to Van Alstine to see what they they think about the match up with an F7, will let you know if I go down that route. the 10RB is interesting for sure. The Rogues are also interesting, will message you privately.

For an affordable but excellent passive pre try one from Luminous Audio. They customize to your system. I recommend the Walker mods. Very transparent.

https://luminousaudio.com/collections/axiom-ii-passive-preamp

https://parttimeaudiophile.com/2012/12/30/mini-review-luminous-audio-axiom-ii-walker-mod/?amp

Quicksilver is very nice and warmish….. So is a Belles 20A if you can find one….

@coaster86 

I think the Van Alstine RB10 (which I have) could be a good pairing for the F7 but the F7 has a 10kΩ input impedance. 
If you buy a new one from Frank , he can make an adjustment to one of the preamp outs to be a super low output impedance that will drive the F7 nicely.  I think it drops the output impedance from something like 2200Ω to 47Ω.