What’s the best tube for a Sonic Frontiers SFL-1 preamp


Hello all,
I just acquired a SF SFL-1 preamp. What’s the sweetest tube any of you SF fans have used in this preamp?
Thanks
skipper320
I run a Genalex, Gold Lion in mine,... fabulous! GL with yours @skipper320; it's a terrific linestage that paired with the right amp will bring you pure sonic joy. I've run mine with TAD, Hibachi Monoblocks, a Cary 808R tuber, and soon a Sugden Bijou (Class A) "AmpMaster". It's a wonderful piece
Mullard 6201 I believe is what I used to run when I had a SFL 1, but that was sometime ago. Very nice preamp with the right tube and for the money. Sold the SFL 1 and moved to a ModWright SWL 9.0 SE which I liked much better. I recall the Mullards were what everyone was using and UpScale Audio recommended too which is where I think I purchased from. I remember the Mullard was much better than the stock tube if that helps.
I just picked up a mint SFL-1 last night , had a "new"  Brimar NOS AT7 but when I set it up I was pretty disappointed....dark, compressed sound it was bad.  Put a new JJ ECC81 in tonight and it sounds great.  

I was actually looking for a pre for my brother but he doesn't want to deal with tubes so I couldn't pass on it for $500....     its built like a tank.  

It will see duty in a second system but for now I am really digging it 
$500 is a steal for an SFL-1 - good for you. It’s a wonderful pre with the right tube to match your speakers and setup. Not really a JJ fan but I’m glad it’s working well for you. I never tried one in this pre. Not surprised by the Brimar but it’s a kinda naturally bright preamp so the previous owner more than likely tried to tame it with his speakers. Genalex and Mullard - can’t go wrong with either if you decide at some point to try something different. GL!